AU2016338436B2

AU2016338436B2 - Patient-matched apparatus and methods for performing surgical procedures

Info

Publication number: AU2016338436B2
Application number: AU2016338436A
Authority: AU
Inventors: George Frey; Paul Ginzburg; Gregory Cooke Kana; Geoff LAI; Sean STARKMAN; Caleb VOELKEL
Original assignee: Mighty Oak Medical Inc
Current assignee: Mighty Oak Medical Inc
Priority date: 2015-10-14
Filing date: 2016-10-14
Publication date: 2021-09-30
Anticipated expiration: 2036-10-14
Also published as: AU2016338436A1; MX2018004479A; AU2016338436A2; KR20180077182A; CA3001898C; EP3361959A4; CA3001898A1; EP3361959A1; CN108366791A; JP2018532498A; KR102638410B1; BR112018007443A2

Abstract

A system and method for developing customized apparatus for use in one or more surgical procedures is disclosed. The system and method incorporates a patient's unique anatomical features or morphology, which may be derived from capturing MRI data or CT data, to fabricate at least one custom apparatus. According to a preferred embodiment, the customized apparatus comprises a plurality of complementary surfaces based on a plurality of data points from the MRI or CT data. Thus, each apparatus may be matched in duplicate and oriented around the patient's own anatomy, and may further provide any desired axial alignments or insertional trajectories. In an alternate embodiment, the apparatus may further be aligned and/or matched with at least one other apparatus used during the surgical procedure.

Description

PATIENT-MATCHED APPARATUS AND METHODS FOR PERFORMING SURGICAL PROCEDURES

FIELD OF THE INVENTION The present disclosure relates to the field of medical devices and is generally directed toward apparatus configurable for use with a specific patient in a surgical setting based on the patient's unique anatomical features, and methods of manufacturing and using the same. BACKGROUND OF THE INVENTION Given the complexities of surgical procedures and the various tools, instruments, implants and other devices used in the procedures, as well as the varying anatomical differentiation between patients who receive those tools, instruments, implants and devices, it is often challenging to create a surgery plan that accounts for the unique and sometimes irregular anatomical features of a particular patient. For example, the implantation of pedicle screws in a vertebral body (as an adjunct or stand-alone stabilization mechanism) is well accepted amongst surgeons who treat various spine pathologies, and although the performance of various pedicle screw constructs have become predictable, there are still multiple challenges with the placement and insertion of the pedicle screws or other bone anchors. The challenges occur when a surgeon is unable to reference boney landmarks due to previous surgery or when the patient's anatomy is irregular in shape. Surgeons now have the ability to readily convert magnetic resonance imaging (MRI) data or computed tomography (CT) data into a data set readable by computer-aided design (CAD) program and/or finite element modeling (FEM) program, which then may be used to create, for example, a custom implant based on the dynamic nature of the anatomical structures the custom implant is designed to associate with. This data, while currently used by surgeons in surgery planning, is largely unused for creating a customized set of instruments or other surgical devices that are designed to complement the patient's unique anatomy. It would therefore be advantageous to provide apparatus suitable for use with a surgical procedure that is adapted and/or configured and/or capable of conforming to a plurality of anatomical features of a particular patient and/or to one or more additional apparatus to assist the surgeon in completing the surgical procedure(s) safely and efficiently, and that otherwise significantly reduces, if not eliminates, the problems and risks noted above. Other advantages over the prior art will become known upon review of the Summary and Detailed Description of the Invention and the appended claims. Reference to any prior art in the specification is not an acknowledgement or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be combined with any other piece of prior art by a skilled person in the art. By way of clarification and for avoidance of doubt, as used herein and except where the context requires otherwise, the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not intended to exclude further additions, components, integers or steps. SUMMARY OF THE INVENTION In an aspect, the present invention provides a patient-specific cutting guide, comprising: a body having a proximal portion and a distal portion; a first slot portion having a first width, the first slot portion extending from the proximal portion to the distal portion of the body of the guide; a second slot portion having a second width, the second slot portion extending from the proximal portion to the distal portion of the body of the guide, the second width different from the first width; the distal portion of the body comprising at least a first patient specific contour on one side of the first slot portion and a second patient-specific contour on the opposite side of the first slot portion for mating with a patient's boney anatomy; the distal portion of the body further comprising at least a third patient specific contour on at least one side of the second slot portion for mating with a patient's boney anatomy; wherein at least one of the first slot portion and the second slot portion is oriented in a path determined from the anatomical data of the patient; and wherein the at least a first, second and third patient-specific contours are determined from the anatomical data of the patient and are shaped to substantially conform to a specific portion of the patient's boney anatomy. Also disclosed herein is a novel system and method for developing customized apparatus for use in one or more surgical procedures. The system and method according to this embodiment uses a patient's unique morphology, which may be derived from capturing MRI data or CT or other data to derive one or more "Patient Matched" apparatus, which comprises complementary surfaces based on a plurality of data points from the MRI or CT data. Each "Patient Matched" apparatus is matched and oriented around the patient's own anatomy, the desired insertional trajectories (which may be verified in a pre-operative setting using 3D CAD software, such as the software disclosed in WO 2008027549, which is incorporated by reference herein in its entirety), and according to one embodiment described herein, other apparatus used during the surgical procedure. According to embodiments, the data obtained from the patient permits the apparatus to be manufactured with defined pathways through the apparatus, which are

2A operatively associated with at least one tool, instrument, or implant, and which permit the at least one tool, instrument or implant to be inserted in the defined pathways in a consistent and reproducible manner. Examples of devices that are implanted or remain in the patient include anchoring devices such as screws, pins, clips, hooks, etc., and implantable devices such as spacers, replacement joints, replacement systems, cages, etc. Also disclosed herein is a preconfigured surgical template which comprises one or more guides for receiving at least one tool. According to this embodiment, the one or more guides further comprise patient-contacting surfaces formed to be substantially congruent with the anatomical features of a patient. The preconfigured surgical template is configured such that the patient-contacting surfaces are configured to contact the plurality of anatomical features in a mating engagement, to ensure proper alignment and mounting of the guide or template, and the guides of the preconfigured surgical template are oriented in a direction selected prior to manufacturing of the preconfigured surgical template to achieve desired positioning, aligning or advancing of a tool within the one or more guides. In one embodiment, a cutting guide is interconnected to a portion of the template or guide. The cutting guide includes a track adapted to guide an instrument operable to remove, or alter, a predetermined portion of the vertebrae of the patient. In one embodiment, the track of the cutting guide includes patient-specific depth, angle, and orientation control to guide the instrument. In one embodiment, the track is formed through a portion of the body. In another embodiment, the track is formed by a portion of an exterior surface of the body. The portion of the exterior surface may comprise a substantially planar surface against which a portion of the instrument may move in a predetermined plane. In one embodiment, the guide further comprises a frame. The frame is configured to be fixed to at least one vertebrae of the patient. In one embodiment, the frame is fixed to screws anchored in the at least one vertebrae. The body of the guide is adapted to releasably interconnect to the frame. In this manner, the guide may be used before, or after, a guide of another embodiment of the present invention used in a surgical procedure. In one embodiment, the at least one track comprises two tracks formed in the body. Further disclosed herein is a patient-specific template. The template is adapted for use in a surgical procedure and includes, but is not limited to, a body having a proximal portion and a distal portion. The distal portion is shaped to substantially conform to a predetermined portion of a vertebrae of a patient. The body includes at least one of a bore and a track oriented in a direction determined from anatomical features of the patient. In one embodiment, the bore or track is adapted to guide an instrument or a fixation device. A portion of the body is adapted to hook at least partially around, and substantially conform to, at least a second predetermined portion of the vertebrae of the patient. In one embodiment, the hook portion of the body comprises an extension of the distal portion of the body. In another embodiment, the extension of the body is designed to hook at least partially around vertebral anatomy selected from the group consisting of: a lamina, a pars interarticularis, an aspect of a transverse process, a spinous process, an inferior articular process, and a superior articular process. In one embodiment, the distal portion of the body of the template is shaped to substantially conform to cut surfaces generated by removal of a portion of the patient's vertebrae. The portion of the patient's vertebrae may have been removed during a previous portion of the same surgical procedure. In another embodiment, at least a portion of the distal portion is shaped to substantially conform to an unaltered portion of the patient's anatomy. In one embodiment, the bore is directed in a cortical bone trajectory. In another embodiment, the bore is directed in a pedicle screw trajectory. In one embodiment a first patient-specific surface is determined from and complementary to the patient's anatomy. In another embodiment, the anatomical feature is a vertebrae and the first patient-specific surface is adapted to anatomically mate with one or more of a lamina, a pars, an articular process, and a spinous process of the vertebrae. In one embodiment, a first trajectory is oriented along a pedicle screw trajectory. Optionally, the first trajectory may be oriented to guide the instrument percutaneously in one of: (1) a cortical trajectory; (2) an Si alar trajectory; (3) an S2 alar trajectory; (4) and S2 alar iliac trajectory; and (5) an iliac trajectory. In one embodiment, the surgical guide is manufactured by a process selected from the group consisting of a rapid prototyping machine, a stereolithography (SLA) machine, a selective laser sintering (SLS) machine, a selective heat sintering (SHM) machine, a fused deposition modeling (FDM) machine, a direct metal laser sintering (DMLS) machine, a powder bed printing (PP) machine, a digital light processing (DLP) machine, an inkjet photo resin machine, and an electron beam melting (EBM) machine. Optionally, the surgical guide may be made of an aluminum alloy, a chromium alloy, a PEEK material, a carbon fiber, an ABS plastic, a polyurethane, a resin, a fiber-encased resinous material, a rubber, a latex, a synthetic rubber, a polymer, and a natural material. Optionally, the surgical guide may be used in one or more of a minimally invasive surgical procedure and a minimal access procedure. In one embodiment, the surgical guide is configured for use in conjunction with a device that employs automated or semi automated manipulation such that placement of the surgical guide with respect to the anatomical feature may be performed remotely by an operator through a computer controller. In another embodiment, the surgical device is identifiable by optical, electronic, or radiological recognition means such that the location and orientation of the surgical device with respect to the anatomical feature is verifiable.

4A

Additional aspects of the present disclosure will become more readily apparent from the Detailed Description, particularly when taken together with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the disclosure. In the drawings: Figs. 1 is a perspective view of an apparatus according to yet another alternative embodiment of the present disclosure; Figs. 2A-2B are perspective views of a cutting guide according to yet another alternative embodiment of the present disclosure; Figs. 3A-3B are perspective views of a cutting tool according to yet another alternative embodiment of the present disclosure; Fig. 3C is another perspective view according to the embodiment shown in Figure 3A depicted with the cutting guide of Fig. 2A; Figs. 4A-4B are perspective views of the cutting tool of the embodiment shown in Figure 3A depicted with the cutting guide of Fig. 2A; Fig. 5A is a front elevation view of a guide of another embodiment of the present invention positioned against a vertebral body; Fig. 5B is another front elevation view illustrating a boring instrument of an embodiment of the present invention inserted in a cannula of the guide of Fig. 5A; Fig. 5C is a side view of a guide sleeve of an embodiment of the present invention positioned proximate to the vertebral body illustrated in Fig. 5A; Fig. 5D is side view of a cutting tool of an embodiment of the present invention inserted into a cannula of the guide sleeve of Fig. 5C; Fig. 5E is a perspective view of the cutting tool and the guide sleeve of Fig. 5D; Figs. 5F-5G are additional perspective views of the cutting tool and the guide sleeve of Fig. 5D; Fig. 6A is a front elevation view of a frame of an embodiment of the present invention interconnected to a portion of a patient's spine; Fig. 6B is a front elevation view of a guide of another embodiment of the present invention interconnected to the frame of Fig. 6A; Fig. 6C is a perspective view of the guide and the frame of Fig. 6B; Fig. 6D is another perspective view of the guide and the frame of Fig. 6B including hidden lines showing the structure of slots formed in the guide; Fig. 7A is a front elevation view of another guide of the present invention;

Fig. 7B is a rear elevation view of the guide of Fig. 7A; Fig. 7C is a bottom perspective view of the guide of Fig. 7A; Figs. 7D-7E are a front elevation view and a perspective view of the guide of Fig. 7A positioned against a vertebral body and including hidden lines showing the structure of slots formed in the guide; Fig. 7F is a side elevation view of the guide of Fig. 7A positioned against the vertebral body; Fig. 7G is another side elevation view of the guide of Fig. 7A positioned against the vertebral body and illustrating cuts formed in the vertebral body; Fig. 8A is a front elevation view of still another guide of an embodiment of the present invention; Fig. 8B is another front elevation view of the guide of Fig. 8A positioned against a vertebral body; Fig. 8C is a side perspective view of the guide of Fig. 8A; Fig. 8D is a side view of the guide of Fig. 8A positioned against the vertebral body; Fig. 8E is a top view of the guide of Fig. 8A positioned against the vertebral body; Fig. 9A is a front elevation view of yet another guide of an embodiment of the present invention; Fig. 9B is another front elevation view of the guide of Fig. 9A positioned against a vertebral body; Fig. 9C is a side perspective view of the guide of Fig. 9A; Fig. 9D is another side perspective view of the guide of Fig. 9A positioned against the vertebral body; Fig. 9E is a side view of the guide of Fig. 9A positioned against the vertebral body; Fig. 1OA is a front elevation view of a frame of an embodiment of the present invention interconnected to a portion of a patient's spine; Figs. 1OB-10C are an elevation view and a perspective view of another guide of an embodiment of the present invention interconnected to the frame of Fig.1OA; Figs. 11A-IIC are perspective views of still another guide of an embodiment of the present invention with Fig. 1IC illustrating the guide of Fig. 11A positioned against a vertebral body that has been altered in a surgical procedure; Figs. 1ID-I1E are a front elevation view and a perspective view of the guide of Fig. 11A positioned against a portion of the patient's spine that has been altered in a surgical procedure and further illustrating the guide in relation to a neural element of the patient; Figs. 12A-12E are perspective views of a guide of yet another embodiment of the present invention with Figs. 12C-12D illustrating the guide positioned against a vertebral body that has been cut to remove portions of the vertebrae and Fig. 12E showing the guide positioned against the vertebral body and neural elements of the patient; Fig. 13A is a perspective view of yet another guide of the present invention; Figs. 13B-13C are a side view and a perspective view of the guide of Fig. 13A positioned in contact with a vertebral body that includes cuts formed using the guide; Fig. 13D is a front elevation view of the guide of Fig. 13A illustrated in a position of use against a portion of a patient's spine and illustrating a neural element of the patient positioned proximate to a recess of the guide; Fig. 13E is a side perspective view of the guide of Fig. 13D in a similar position of use; Fig. 14A is a perspective view of a model of an embodiment of the present invention; Fig. 14B is a side elevation view of the model of Fig. 14A; Fig. 14C is rear elevation view of the model of Fig. 14A; Figs. 14D-14E are a perspective view and a side elevation view of the model of Fig. 14A positioned in contact with a vertebral body; Fig. 15A is a front elevation view of another model of an embodiment of the present invention; Fig. 15B is a rear elevation view of the model of Fig. 15A; Fig. 15C is a rear perspective view of the model of Fig. 15A; Fig. 15D is another front elevation view of the model of Fig. 15A in a position of use against a vertebral body; Fig. 15E is a front perspective view of the model of Fig. 15D; Fig. 15F is a top perspective view of the model of Fig. 15D; Fig. 16A is a front perspective view of another embodiment of a model of the present invention; Fig. 16B-16C are a front elevation view and a perspective view of the model of the embodiment of Fig. 16A positioned proximate to a vertebral body;

Fig. 17A is a perspective view of yet another guide of an embodiment of the present invention adapted to interconnect to a model of an embodiment of the present invention and showing the guide and the model in a disassembled state; Fig. 17B is a perspective view of the model and the guide of Fig. 17A in an assembled state; Fig. 17C is a front elevation view of the model and the guide of Fig. 17B; Figs. 17D-17E are a perspective view and a front elevation view of the model and the guide of Fig. 17B positioned proximate to a vertebral body; Figs. 18A-18B are a perspective view and a side elevation view of still another embodiment of a model of the present invention; Figs. 18C-18D are a perspective view and a side elevation view of the model of Fig. 18A interconnected to a frame of the present invention similar to the frame of Fig. 1OA, illustrating the model in a position of use proximate to a portion of the patient's spine; Fig. 19A is a perspective view of another embodiment of a model of the present invention; Fig. 19B is a side perspective view of the model of Fig. 19A; Figs. 19C-19D are views of the model of Fig. 19A in a position of use interconnected to a frame of the present invention, the frame fixed to a portion of a patient's spine; Fig. 20A is a perspective view of a three-dimensional model of a unique grouping of a portion of patient's spine of an embodiment of the present invention and illustrating a portion of the spine being removed; Fig. 20B is a side elevation view of the three-dimensional model of Fig. 20A; Fig. 20C is a perspective view of the removed spine portion after some of the removed spine portion has been cut away; Fig. 20D is a side elevation view of the three-dimensional model of Fig. 20D after the model has been moved to close a gap formed after a portion of the spine was removed; Fig. 20E is a side elevation view of the three-dimensional model of Fig. 20B and further illustrating an alignment indicator of the present invention interconnected to the three-dimensional model and with the model showing the alignment of the patient's spine before the planned surgical procedure; Fig. 20F is another side elevation view of the alignment indicator of Fig. 20E showing the alignment of the patient's spine after the planned surgical procedure;

Fig. 21A is a perspective view of a coronal alignment verification tool of an embodiment of the present invention positioned proximate to a portion of a patient's anatomy; Figs. 21B, 21C, and 21D are front, bottom, top elevation views, respectively, of the tool of Fig. 21A; Fig. 22A is a perspective view of another embodiment of a coronal alignment verification tool of the present invention positioned proximate to a portion of a patient's spine; Figs. 22B, 22C, and 22D are a front, top, and right side elevation views of the tool of Fig. 22A; Fig. 23A is a front elevation view of another tool of an embodiment of the present invention for verification of coronal alignment; Fig. 23B is a right side elevation view of the tool of Fig. 23A; Fig. 23C is a perspective view of the tool of Fig. 23A; Fig. 23D is a front view of the tool of Fig. 23A proximate to a portion of the patient's spine and aligned in relation to the sagittal plane; Fig. 23E is a side view of the tool of Fig. 23D proximate to the patient's spine and aligned in relation to the coronal plane; Fig. 24A-24B illustrate two side view of an alignment assembly in a position of use interconnected to a portion of a patient's spine before and after the alignment of the spine is altered during a planned surgical procedure; Figs. 25A-C are various views of yet another patient-specific guide of an embodiment of the present invention for contacting surfaces and trajectories in a patient's spine;

Figs. 26A-26C are various views of the guide of Figs. 25A-C shown in relation to a vertebral body of a patient; Figs. 27A-27C are various views of another patient-specific guide of another embodiment of the present invention for contacting surfaces and trajectories in a patient's spine; Figs. 28A-28B are various views of still another embodiment of a patient-specific guide of an embodiment of the present invention; Figs. 29A-29C are various views of another patient-specific guide of an embodiment of the present invention;

Figs. 30A-30C are various views of a patient-specific guide for contacting surfaces and trajectories in a patient's spine according to yet another embodiment of the present invention; Figs. 31A-31C are various views of a guide of an embodiment of the present invention further comprising secondary and tertiary sleeves of still another embodiment of the present invention;

Fig. 32A-32B are various view of still another embodiment of a patient-specific guide of an embodiment of the present invention; Figs. 33A-33B are perspective views of another embodiment of a patient-specific guide of the present invention; Figs. 34A-34B are a bottom plan and a perspective view of another patient-specific guide of the present invention; Figs. 35A-35C are perspective views of still another patient-specific guide of the present invention; Figs. 35E-35F are additional perspective views of the patient-specific guide of Figs. 35A-35D positioned against a vertebral body; Fig. 36A is a perspective view of yet another patient-specific guide of an embodiment of the present invention in which cannulae of the guide do not contact vertebrae of a patient's spinal column; Figs. 36B-36C are perspective views of the patient-specific guide of Fig. 36A positioned against a vertebral body and illustrating distal ends of the cannulae separated from the vertebral body by a predetermined distance; Figs. 36D-36F are perspective views of another patient-specific guide similar to the guide of Fig. 36A, the guide adapted to be positioned within an incision against a patient's boney anatomy and including external cannula adapted to remain outside of a skin envelope and further including internal cannula arranged to be within the skin envelope, the external and internal cannula being collinearly aligned;

Figs. 37A-37B are a side perspective view and a top perspective view of another embodiment of a patient-specific guide of the present invention; Figs. 37C-37D are perspective views of the patient-specific guide of Fig. 37A positioned against a vertebral body;

Fig. 38 is an exploded perspective view of an interbody guide for facilitating a surgical procedure according to one embodiment of the present disclosure; Fig. 39 is a right side elevation view of another embodiment of an interbody guide; Fig. 40 is a perspective view of the interbody guide shown in Fig. 38 with a different guide sleeve inserted in the aperture of the interbody guide; Fig. 41 is another perspective view of the interbody guide shown in Fig. 38 with still another guide sleeve inserted in the aperture; Fig. 42 is a perspective view of the interbody guide shown in Fig. 38 between two vertebral bodies; Figs. 43A-43B are bottom rear perspective views of the interbody guide shown in Fig. 42 proximate to the superior vertebral body; Figs. 44A-44B are perspective views of the interbody guide shown in Fig. 42 with the guide sleeve of Fig. 40 inserted in the aperture; and Figs. 45A-45B are perspective views of another interbody guide between two different vertebral bodies.

DETAILED DESCRIPTION As shown in the appended Figures and described in further detail herein, the present disclosure relates to a novel system and method for developing a variety of customized, patient-matched apparatus for use in a diverse number of surgical procedures. The system and method uses a patient's unique morphology, which may be derived from capturing MRI data, CT data, or any other medical imaging device to derive one or more patient-matched apparatus, which comprise complementary surfaces to those encountered during the surgical procedure(s) as derived from a set of data points. According to various embodiments described herein, the patient-matched apparatus may further comprise desired axes and/or insertional trajectories. Multiple embodiments of the disclosure are depicted in Figs. 1-45. Figure 1 is a perspective view of an apparatus for facilitating a surgical procedure according to an embodiment of the present disclosure. In this embodiment, the apparatus formed by the system and method described above comprises a cutting guide 10. The guide 10 can be used to orient a cutting tool to alter and, optionally, remove portions of the anatomy of the patient. A variety of cutting tools, including (but not limited) routers, burrs, and osteotome may be used with the guide. The guide 10 illustrated in Fig. 1 is a laminectomy guide adapted to facilitate the use of surgical cutting instruments to alter the patient's lamina.

However, guides of the present invention may be adapted for use in procedures to alter any portion of the patient's anatomy. In one embodiment, the guides of the present invention may be used in procedures to alter posterior portions of the patient's anatomy, including without limitation facet joints, transverse processes, articular processes, and spinous processes of a patient. In the embodiment of the present invention illustrated in Fig. 1, the guide 10 is adapted to fit directly to aspects of a patient's anatomy. More specifically, the guide is positioned proximate to a medial vertebrae VM between a superior and inferior vertebrae VS, VI. Thus, the laminectomy cutting guide 10 also comprises a lower patient-contacting surface 14 which permits the laminectomy cutting guide 10 to mate with one or more vertebral bodies. The patient specific surface 14 can be specific to any portion of the patient's anatomy, such as lamina, transverse processes, articular processes, spinous processes, etc. Alternatively, the guide 10 can be interconnected to a frame as described in more detail herein. Surface 14 may be adapted to at least partially hook around a portion of the patient's anatomy. For example, the surface 14 may comprise multiple portions 14A, 14B that are adapted to contact two different planes formed by two distinct portions of the patient's anatomy. The laminectomy cutting guide 10 illustrated in Fig. 1 further comprises at least one alignment channel 16 for inserting a guide wire or other securing element, and a cutting slot 20 for directing the path of a blade or other cutting edge. The alignment channel 16 may receive a fixture, such as a temporary fixation device, to temporarily fix the guide 10 to the patient's spine. The temporary fixation device may be a pin or screw such as those known to one of skill in the art. Placing a fixture through the channel 16 can increase stability of the guide during use of the guide in a cutting procedure. Optionally, the channel 16 may comprise a cannula adapted to receive a tool, such as a tool for forming a bore in the patient's anatomy. Thus, in one embodiment, the alignment channel 16 may optionally comprise a bore adapted to guide an instrument or a fixation device, such as a pedicle screw.. The slot 20 can have any shape determined to guide cuts for a planned surgical procedure for a particular patient. For example, the slot may have a shape to guide instruments to provide straight, concave, convex, or 'chevron' shaped cuts. In one embodiment, the slot includes multiple portions 20A, 20B, 20C. The cutting slot 20 may be sized or shaped to prevent the use of an inappropriate tool. Additionally, the slot may be shaped to guide a cut around a neural element of the patient. Accordingly, the slot 20 can be used to guide instruments along a presurgically planned pathway while controlling instrument orientation and depth. Further, the width of the slot 20 may change to control the size of a cutting tool that fits through the slot. For example, slot portion 20A may have a different dimension than portions 20B, 20C. In one embodiment of the present invention, slot portion 20A has a different width than slot portions 20B, 20C. Stops may be formed in the slot 20 to limit or control the depth of insertion of the cutting tool. The stops may be specific to the patient's anatomy and allow for protection of neural elements of the patient. The slot 20 may also be keyed to ensure depth control while cutting. For example, the slot 20 may include a key that alters the depth of cutting by the tool as the tool is guided through the slot. The key may correspond to a feature, such as a protrusion 144 on the tool 140, described in more detail in conjunction with Fig. 3, that limits the depth of insertion of the tool. Optionally, a sleeve 24 or an insert may be selectively retained in the slot 20. The insert 24 includes a slot 26 for a cutting tool. The sleeve 24 separates and protects the guide 10 from the cutting tool. For example, if the guide 10 is formed of a material that may be cut by the cutting tool, the size and shape of the slot 20 could be changed by the cutting tool. The insert 24 is provided to prevent the cutting tool from altering the slot 20. In this manner, the insert may prevent deviation from a planned surgical procedure. It will be appreciated that the insert 24 may have any size and shape selected to be at least partially received in the slot 20. Further, the insert may project at least partially from the proximal side of the guide 10. In one embodiment, the insert 24 has a cross sectional profile substantially the same as the cross-sectional profile of the slot 20. The insert 24 may have a length that is the same as, or similar to, the depth of the slot. In one embodiment, the slot 20 may be sized to receive more than one sleeve 24. Each sleeve may be adapted to guide a different tool or define a different cut. For example, a first sleeve may be introduced into the slot to guide a first tool to create a first cut. The first sleeve may then be replaced by a second sleeve introduced into the slot. The second sleeve may guide a second tool to create a second cut. The second sleeve may have a different size and shape than the first tool. In one embodiment, the second cut alters the first cut. Alternatively, in another embodiment, the second cut does not intersect the first cut. The insert 24 may be formed of any material that is of sufficient strength that breaking and/or flaking of the insert material is avoided. Accordingly, the insert 24 may withstand the effects of high-speed cutting tool without damaging the insert or permitting material from the insert to become deposited in the cutting site as well as re-use of the insert. The insert material must also withstand the high temperatures encountered during sterilization. In one embodiment the insert is formed of a metal or metal alloy, although other materials are contemplated. One benefit of a metallic insert is the ability to "trephine" or machine a cutting surface to permit the distal end of the insert to "bite" into the bone and provide means for fixation of the insert. Forming a trephine on the distal end may provide further stabilization of the guide during a cutting operation. In another embodiment, the insert is formed of any material that is harder than the material of the guide. The insert 24 may be adapted to receive different types and sizes of tools. Additionally, or alternatively, the insert may be operable to receive only one particular tool. Inserts can also be provided to ensure cuts are performed in a preplanned sequence. For example, when the slot of a guide 10 has a compound shape, such as slot 20 with three different portions 20A, 20B, 20C, the surgical plan may include a first operation through slot portion 20A followed by operations through portion 20B and then 20C. Accordingly, a first insert 24A may be provided to receive a tool in portion 20A through slot 26A while blocking access to slot portions 20B, 20C. After the first operation is completed, the first insert may be replaced with second and third inserts 24B, 24C to allow access to slot portions 20B, 20C. One of the inserts, for example, insert 24B, may have a different length that the other inserts. Additionally, or alternatively, the insert 24 may include stops to limit an angle of use of the cutting tool during the surgical procedure. Indicia may be positioned on the guide and the inserts to indicate a sequence of use conforming to the sequence of operations in which the guide is to be used. The indicia may also indicate a tool to be used, a direction of a cut to be performed, or a particular portion of the patient's anatomy targeted by a cut. The indicia may comprise computer readable elements, such as a bar code or an RFID. Thus, the indicia may be used to identify the guide and to retrieve information about a procedure to be performed with the guide 10. In one embodiment, the cutting guide 10 designed following acquisition of a scan of the patient's anatomy with a medical imaging device. The scan may be performed by a CT scanner, an MRI scanner, or any other medical imaging device. The scan is segmented into 3D models of each vertebra. These 3D models are then modified in CAD to simulate the correction desired by the surgeon. Once the desired correction is appropriately simulated, a guide 10 is generated that will allow the surgeon to make the planned corrections intraoperatively. Although shown in Fig. 1 as a generally rectangular prism, it is expressly understood that other geometrical shapes for the laminectomy cutting guide 10 are equally as practical, and considered within the scope of the disclosure. The cutting guides of the present invention can be used as physical cutting guides. Additionally, the cutting guides may be used as an aid to indicate to surgeons the angle and location of osteotomy cuts so that neural elements in the patient's spine are not harmed. The guides may also be used pre-surgically on models of the patient's anatomy to test or practice the planned surgical procedure. Referring now to Figs. 2A-2B, further illustrations of a cutting guide 110 are provided. According to one embodiment, the cutting guide 110 comprises a plurality of patient-specific contacting surfaces 114 about at least one surface of the cutting guide and an alignment channel 116. The contacting surfaces may comprise portions 114A, 114B adapted to hook at least partially around portions of the patient's anatomy. In one embodiment, the contacting surfaces 114 are adapted to conform to cut surface generated by removal of a portion of the patient's anatomy. The cutting guide further comprises, in a preferred embodiment, a patient-specific slot or "track" 120 for facilitating insertion of a cutting instrument (as shown in Figures 3-4) and controlling the depth of insertion for that instrument to prevent unnecessary cutting of the underlying surface during a particular surgical procedure by further providing one or more instrument contacting surfaces 122. According to the embodiment shown in connection with Figs. 2-4, the cutting guide 110 may be provided for a laminectomy. According to other embodiments, the patient-specific guide may be fabricated for use in performing a corpectomy, a Pedicle Subtraction Osteotomy (PSO), a Smith-Peterson Osteotomy (SPO), a Vertebral Column Resection (VCR), or an Asymmetric Osteotomy (in either the sagittal or coronal plane), among others. These patient-specific cutting guides 10, 110 may be fabricated from patient anatomical data, and may assist in performing complex procedures with greater certainty in their outcomes. For example, certain osteotomies, specifically PSO and SPO, require a great deal of surgical skill and are often time consuming. By using a patient-specific guide, a surgeon may confirm positioning and alignment of the cutting trajectory and path prior to initiating the procedure, and in furtherance of the disclosure provided above in relation to Figs. 2-4, may also provide a degree of depth control essential for avoiding contact with vascular and neural elements. In one embodiment, the cutting tool 140 associated with the cutting guide 110 shown in Figs. 2-4 is typical of the type of tools currently used in surgical procedures. According to another embodiment, a specialty cutting bur or tip 142 may be included with the instrument to facilitate further control of the location and depth of the instrument, as described in further detail below. For example, as shown in Figs. 3A-3C, the cutting portion of the instrument may have a protrusion 144 that prevents greater insertion of the instrument 140 into the cutting guide 110 than required for the patient-specific procedure. In one embodiment, the position of the protrusion 144 on the cutting tip 142 may be adjusted by a user. The protrusion 144 may be of any form adapted to interact with contact surfaces 122 of the slot 120 to control the use of the cutting tool 140. In one embodiment, the protrusion 144 is a bearing. In another embodiment, the protrusion is a track ball. In still another embodiment, the protrusion is generally disc-shaped. As shown in greater detail in Figs. 4A-4B, the protrusion 144 may be inserted into a first portion 120C of the "track" 120 of the cutting guide 110. Second or third deeper portions 120A, 120B of the "track" of a cutting guide (through which the cutting surface is permitted to travel), may prevent insertion or withdrawal of the protrusion 144, thereby insuring proper depth of the cutting instrument. Further geometrical configurations other than those shown in Figs. 4A-4B may be provided that allow the protrusion 144 to move horizontally with respect to the top surface of the cutting guide, and in some instances laterally and downwardly into the track 120 of the cutting guide. In this embodiment, the cutting instrument 140 would therefore be permitted to move at a certain depth about a patient's anatomy in a certain location of the "track" 120 of the cutting guide, but achieve a greater depth at yet other locations about the "track" 120 of the cutting guide 110. Thus, the depth permitted with respect to the instrument 140 relative to the cutting guide 110 may be variable about the "track" 120 of the cutting guide. It will be appreciated by one of skill in the art that the size and location of the surfaces 122 may be altered as desired. Accordingly, in other embodiments of the present invention, the instrument 140 may be inserted and removed from different portions of the track 120, or from two or more portions of the track. Further, in one embodiment, the track 120 and the instrument 140 include protrusions that interact to permit the tool to be inserted in only a first portion of the track, for example portion 120C, and removed from only a second portion of the track, such as portions 120A or 120B.

Referring now to Figs. 5A-5F, a guide sleeve 210 of another embodiment of the present invention is described. The sleeve 210 is adapted for use in a posterior osteotomy, also known as a Smith-Petersen Osteotomy (SPO) or a "ponte osteotomy" procedure. As will be appreciated by one of skill in the art, during a posterior osteotomy, a portion of bone is removed from the back of the patient's spine. Portions of the posterior ligament and facet joints may also be removed from targeted portions of the patient's spine. The osteotomy may be performed at one or multiple locations along the spine to correct the alignment of the patient's spine. In one embodiment of the present invention, a surgical guide 246, guide sleeve 248 and drilling insert or sleeve 249 assembly according to an embodiment of the present disclosure is positioned proximate to a targeted portion of the patient's anatomy. The drill sleeve 249 (placed through the patient-matched guide sleeves 248 and into the bone at opposing, dissimilar angles) provides additional fixation of the guide 246 to the vertebra V. The guide 246 is used to introduce a bore (not illustrated) into the pedicle for the guide sleeve 210. The trajectory of the bore is specifically planned and controlled by sleeve 248 for the drilling sleeve 249. The placement of bore is selected in such a way that neural elements are protected from the tool 247 inserted through the drilling sleeve 249. The trajectory of the bore is selected to be a predetermined distance away from the neural elements so that the tool 247 is a safe distance away. In one embodiment, the bore is at least 0.25 mm away from the patient's neural elements. However, it will be appreciated that any predetermined distance separating the bore from neural elements may be used. In another embodiment, the distance is from about 0.1 mm to about 3 mm. Referring now to Figs. 5C-5G, once the pedicle is cannulated, the surgical guide 246 may be removed from the vertebrae V. A guide sleeve 210 is inserted to a controlled depth within the bore. The cutting tool 240 is inserted into a cannula 225 of the sleeve 210 and activated. The tool includes a surface 242 that cuts from the interior to the exterior of the pedicle. In one embodiment of the present invention, the guide sleeve 210 includes an aperture 218 for the cutting surface 242. The aperture 218 may be spaced from the distal end of the guide sleeve 210 by a predetermined amount to control the depth of the cut. In another embodiment, the aperture is positioned at the distal end of the sleeve 210. The cutting surface 242 may be mechanically or electrically actuated. The cutting surface 242 may comprise a reciprocating or a rotating blade, or any other type of cutting tool. In one embodiment, the orientation or length of the cutting surface 242 may be altered by the surgeon during the surgical procedure. Optionally, in another embodiment of the present invention, the tool is operable to ablate portions of the pedicle to complete the cut. For example, the tool may comprise a laser adapted to burn through portions of the pedicle from within the bore. In another embodiment, the tool may comprise a heated surface to burn or otherwise remove portion of bone or tissue. Once the cut has been made, the posterior column of the vertebra can be removed. Referring now to Figs. 6A-6D, an embodiment of a guide 310 comprising a frame 330 is illustrated. The guide 310 is adapted for use in a posterior osteotomy, although other procedures are contemplated. The frame 330 may have a patient-specific shape. For example, the frame may be adapted to flex or snap into a position in contact with a transverse process T or other portion of the patient's anatomy. Alternatively, the frame 330 may be designed to be used in surgical procedures for any patient. In use, the frame 330 is interconnected to fixation devices 334 positioned in predetermined portions of the patient's anatomy, such as the patient's vertebrae, V. In one embodiment, as illustrated, the vertebrae V include an inferior vertebra VI, a medial vertebra VM, and a superior vertebra VS. The fixation devices 334 may be pedicle screws. Although two fixation devices 334 in each of the inferior and superior vertebra VI, VS are illustrated in use with the frame 330 of the embodiment of Fig. 6, it will be appreciated that any number, including fewer screws, may be used with the frame. The size and shape of the frame 330 may be selected to only permit the frame to be interconnected to the screws when the frame is in a pre-planned orientation. For example, the embodiment of the frame 330 illustrated in Fig. 6A has a shape that only permits the frame to be interconnected to the four pedicle screws 334 when the frame is in one predetermined orientation. The pedicle screws 334 or other fixation devices may be placed in the vertebrae using any tool or guide. Pre-existing pedicle screws from a previous surgery may be used with the frame. One or more of the pedicle screws may also be positioned using a pedicle screw guide of an embodiment of the present invention, for example, the guide 246 described above. Other embodiments of pedicle screw guides are described in the Applicant's U.S. Patent 9,198,678 which is incorporated herein in its entirety. The frame 330 may retract soft tissue in the surgical area. Further, reference points or indicia may be provided on the frame 330 for docking the osteotomy guide 310. The indicia may indicate a planned orientation or alignment of the guide. The shape of the frame 330 may only permit docking of the guide when the guide 310 is in a pre-planned orientation with respect to the targeted vertebrae. The frame 330 may also be used to distract the vertebrae in a target area of the patient's spine by a predetermined amount. The distraction provided by the frame may ensure a cut is formed at a predetermined angle. The distraction may also be necessary to provide access to a predetermined portion of the patient's anatomy. Once interconnected to the pedicle screws 334, the frame 330 may also prevent unintended movement of the vertebrae during the surgical procedure. The frame may also be planned such that it increases the distraction of the construct to provide the surgeon with a larger window through which the surgery can be completed. In this embodiment the frame connects the superior vertebra VS (above the osteotomy location of the medial vertebra VM) to the inferior vertebra VI (below the osteotomy location). In one embodiment, the frame is positioned lateral to the pedicles so that the posterior anatomy of the medial vertebra VM is substantially unobstructed by the frame 330. It will be appreciated by one of skill in the art that the frame may be sized to span any number of vertebra. Once the frame 330 is interconnected to the pedicle screws, the guide 310 is interconnected to the frame. The guide 310 is presurgically planned to align on the frame 330 with targeted portions of the medial vertebrae VM in a patient-specific location so that cuts are made accurately. Although the embodiment of the guide 310 illustrated in Figs. 6B-6D is shown as one piece, it will be appreciated that in other embodiments the guide could include multiple pieces or a series of cutting guides that are placed in a specific order to generate a series of planned cuts. In embodiments of guides comprising multiple pieces, each piece of the guide may be keyed to interconnect in a specific order and location to other pieces of the guide. In one embodiment, the guide 310 does not contact the patient's anatomy. Said another way, the guide 310 is adapted to float over a surgical area when the guide is interconnected to the frame 330. In another embodiment, at least a portion of the guide 310 is adapted to contact the patient's anatomy. The guide may include slots 320 and apertures 328. The aperture 328 may be positioned to prevent contact with portions of the patient's anatomy. For example, the guide 310 of the embodiment illustrated in Figs. 6B-6D includes and aperture 328 to at least partially receive the spinous process S of the medial vertebra VM. The aperture 328 and surfaces of the guide proximate to the patient's anatomy may include patient specific contours adapted to substantially conform to predetermined portions of the patient's anatomy. In this manner, the alignment of the guide with a planned portion of the patient's anatomy may be enhanced. The patient specific contact contours may also improve the stability of the guide 310 during the procedure. The slots 320 are positioned and have sizes to guide tools used during the surgical procedure, similar to the slots 20, 120 of the guides 10, 110 described above. The slots 320 may have shapes and be positioned at a variety of angles to guide tools, including cutting tools. Each slot 320 may have a unique size and orientation. Thus, slots may be adapted to receive different tools, or only one specific tool. Features, such as protrusions, may be formed in the slot and interact with features of the tools to control the depth of insertion of the tool, direction of use of the tool, and insertion and removal points of the tool. Inserts, similar to the insert 24 described above, may be formed to be positioned in the slots 320 to prevent damage to the slots or to ensure proper use of tools during the procedure. Referring now to Figs. 7A-7G, still another embodiment of a guide 410 of the present invention is illustrated. The guide 410 is adapted for use in pedicle subtraction osteotomies (PSO) and asymmetrical pedicle subtraction osteotomies (APSO) for a single vertebral level. The size and shape of the guide may be selected to fit the guide across the surface of the vertebra V. The guide 410 may comprise one piece adapted to target one portion of the vertebra. Alternatively, the guide may be formed in two or more pieces to target a variety of locations of the vertebra. The pieces can guide an ordered sequence of cuts in the vertebra. In one embodiment, the pieces may be interconnected in sequence during the surgical procedure to form the guide 410. In one embodiment, the guide 410 may fit directly to the posterior aspects of a patient's anatomy, such as lamina, transverse processes, articular processes, spinous processes, etc. Accordingly, a variety of patient matching surfaces 414 may be provided on the guide 410. Additionally, or alternatively, the guide 410 could also fit to a surface of the spine that has previously been cut. In one embodiment, the previous cut may be performed using an initial guide of the present invention. The initial guide is adapted to guide a cutting tool used to generate a surface of the vertebrae. The guide 410 may be designed to fit to the surface generated using the initial guide. Additional cuts in the altered vertebrae can then be performed using the guide 410. Alternatively, the guide 410 may be interconnected to any frame described herein, including frames 330, 730. The guide 410 includes slots 420 to guide surgical tools, including cutting tools such as routers, burrs, and other similar device, along a track to aid in removal of pedicles.

The slots 420 may be the same as, or similar to, the slots of guides 10, 110 described above. The slots have a size and orientation selected to constrain cutting tools to pre surgically planned entry points and angles of cuts for the procedure. As will be appreciated, the slots 420 may be oriented in a plane transverse to the proximal surface portion of the guide 410. The slots can be planned to guide tools to make cuts that are substantially linear, concave, convex, curvilinear, or "chevron" shaped. Further, as described above, the slots 410 may receive sleeves 24 and can include stops and keys to guide or restrict movement of the surgical tool. Optionally, the guide 410 includes an alignment channel or cannula 416. The cannula 416 is adapted to guide a fixture tool or anchor, such as fixture 434, into the vertebra. It will be appreciated that the cannula 416 may be positioned in a variety of locations on the guide. Further, more than one cannula can be provided. In one embodiment, as illustrated in Figs. 7E-7G, the guide 410 is anchored to the vertebrae by an anchor 434. After the cuts 450 (illustrated in Fig. 7G) have been completed in the pedicle of the vertebrae V, the entire cut portion of the pedicle can be removed along with the guide 410 by pulling the anchor 434 away from the vertebrae V. Figs. 8A-8E illustrate another embodiment of a guide 510 of the present invention. In one embodiment, the guide 510 is adapted for use in PSO and APSO procedures. The guide is sized to partially span adjacent superior VS and inferior VI vertebrae. Similar to the guide 410, guide 510 includes patient specific contact surfaces 514 adapted to substantially conform to the patient's anatomy. For example, in one embodiment, the distal surface 515 of the guide includes a plurality of patient specific contours. At least one portion of the distal surface 515 may be adapted to contact a cut surface formed by removal of a portion of the patient's anatomy. A number of apertures may be formed through the guide to target, avoid, or align with, predetermined portions of the patient's anatomy. For example, an aperture 528 may be formed through the guide 510 with a shape selected to allow the spinous process S to at least partially pass through the guide. Patient specific surfaces 514 may be formed within the aperture 528. The guide may further include a pedicle aperture 529 with a pre-planned shape to at least partially receive the pedicle P of the patient. The pedicle aperture 529 may also include interior surfaces that are patient specific. A surgeon may insert cutting tools into the aperture 529 to remove portions of the pedicle P. The pedicle aperture may be shaped to prevent over insertion of a tool into the vertebrae. Further, keys may be formed around the aperture 529. In conjunction with a protrusion formed on the tool, such as the protrusion 144 described above, the keys may control or alter the depth of insertion of the tool as the surgeon move the tool around the aperture 529. The guide 510 may also include a cutting track 520. The track 520 is similar to slots 20, 120, 320 described above and may receive a guide sleeve the same as, or similar to, sleeve 24. In one embodiment of the present invention, the cutting track 520 is adapted to target facet capsules of each of the superior VS and inferior VI vertebrae. The surgeon may use the cutting track 520 to separate the adjacent facet capsules of the adjacent vertebrae. As will be appreciated, other cutting tracks or cutting slots may be provided on the guide to control other planned cuts. Although not illustrated, the guide 510 may include a cannula similar to cannula 16, 416 describe above. A fixture implanted in the vertebrae may be received in the cannula to at least temporarily interconnect the guide 510 to the vertebrae. Optionally, the cannula may be adapted to guide an instrument, including a boring instrument or cutting tool 240. Referring now to Figs. 9A-9E, still another embodiment of a guide 610 of the present invention is illustrated. The guide 610 is similar to guide 510 and includes a distal surface 615 that may include patient specific contact surfaces. At least one of the contact surfaces may be adapted to substantially conform to an unaltered portion of the patient's anatomy. Another portion of the distal surface 615 may be adapted to substantially conform to a portion of the patient's anatomy altered, for example, by a cut. An aperture 628 adapted to at least partially receive the spinous process S may be provided. The aperture 628 may include patient specific surface 614. The guide 610 is adapted to target each pedicle P of a vertebrae V. Accordingly, the guide includes two pedicle apertures 629. The apertures are the same as, or similar to, the pedicle aperture 529 of the guide 510 describes above. In one embodiment, each pedicle aperture 629A, 629B may have a unique shape specific to the patient's anatomy. Optionally, the guide 610 may have a thickness determined such that the pedicles P do not project beyond a plane formed by a proximal surface as illustrated in Figs. 9D, 9E. Voids 617 may also be formed in portions of the guide to align the guide with the vertebrae V. The voids may be in various positions. Further, the voids 617 may extend partially or completely through the guide 610. In addition, a protrusion 619 may extend from the distal surface 615 of the guide. The protrusion may be adapted to fit to a selected portion of the posterior of the vertebrae. Optionally, the void 617 or the protrusion 619 may at least partially hook around a portion of the patient's anatomy. In this manner, the void 617 and protrusion 619 contact distinct portions of the patient's anatomy compared to other portions of the distal surface 615. The void and protrusion thus provide references to indicate when the guide 610 is positioned in a predetermined position in relation to the patient's anatomy. Said another way, the void 617 or protrusion 619 will prevent the guide 610 from seating properly when the guide is in an improper position. Thus, the guide will not be stable, providing tactile feedback to the user that the guide is not in the correct position. In one embodiment, the protrusion 619 is adapted to fit the guide to a portion of a transverse process or a lamina. Each void 617 or protrusion 619 may further include patient specific surfaces. Referring now to Figs. 10A-10C, a guide 710 of another embodiment of the present invention is illustrated. In one embodiment, the guide 710 is adapted for use in a PSO or an APSO procedure. Portions of the posterior of the superior vertebrae VS, medial vertebrae VM, and the inferior vertebrae VI (such as the transverse process, spinous process, lamina, and/or pedicles) are removed by cuts 750 prior to the use of the guide 710. A frame 730 is interconnected a portion of the patient's spine. The frame generally comprises a medial member 732 connecting two transverse members 733. In one embodiment, the frame 730 is interconnected to the superior vertebrae VS and the inferior vertebrae VI. Pedicle screws 734 positioned in the superior and inferior vertebrae may be used to secure the frame to the vertebrae. The frame 730 may be similar to, and include the features of, the frame 330 described above. Thus, the frame 730 may preserve an existing amount of distraction. In one embodiment, the frame is used to preserve the relationship between the medial vertebrae VM and the adjacent superior and inferior vertebrae VS, VI. Alternatively, the frame is adjustable in order to change the distraction of the construct as necessary. For example, in another embodiment of the present invention, the medial member 732 of the frame may have a length that is adjustable during a surgical procedure, which increases or decreases the distance between the transverse members 733. The medial member 732 may comprise a first portion that fits within, or adjacent to, a second portion. The medial member may further comprise a rack and pinion system, threads, or other means for altering the length of the medial member 732 to provide a desire amount of distraction between vertebrae VS, VM, VI. As will be appreciated by one of skill in the art, the frame may have different shapes and sizes. For example, in another embodiment, the frame 730 may comprise two medial members. Each medial member 732 may have a length that is independently adjustable. Once the frame is in place, the guide 710 is interconnected to the frame. In one embodiment, at least a portion of the guide 710 is adapted to contact a cut surface 750 of a patient's vertebrae. Another portion of the guide 710 may have patient-specific surface adapted to conform to an uncut portion of the patient's vertebrae. The guide includes cutting tracks 720. The tracks 720 are similar to the other slots described herein, including, without limitation, slots 20, 120, 320. After the guide is interconnected to the frame, the tracks are used to guide cuts into the vertebrae along a predetermined trajectory. Each track 720A, 720B may have a unique patient specific shape. Further, track 720A may have a size and width adapted to receive a specific tool that is different than the tool associated with track 720B. In one embodiment, the guide 710 includes two tracks to separate the pedicle from the medial vertebrae VM. The tracks may enable the separation of the pedicle in a single cut. The guide 710 may include apertures to guide cuts in other portions of the vertebrae VS, VM, and VI similar to guides 510, 610. Although not illustrated, the guide 710 may also include cannula similar to cannula 16, 416 describe above. The cannula may receive a fixture (similar to fixture 434) to interconnect the guide 710 to the targeted vertebrae VM. Optionally, the fixture may be placed in a portion of the vertebrae, such as the pedicle, planned for removal by cuts guided by the tracks 720. In this manner, after the cuts are completed, the guide 710 can be removed from the frame to remove the severed portions of the pedicle. In another embodiment, the cannula is adapted to guide an instrument, such as a boring device. Referring now to Figs. 11-12, embodiments 810A, 810B of guides of embodiments of the present invention are illustrated. The guides are adapted fit to a cut surface 850 of a vertebrae VM that has been formed by removing a portion of the vertebrae. The surface 850 may be formed by a cut guided by another any other guide of the present invention. The guides 810A, 810B may also include patient-specific surfaces 814 that are adapted to substantially conform to predetermined portions of the vertebrae. A first portion 814A may be adapted to contact and substantially conform to a cut surface 850 of the patient's anatomy. A second portion 814B of the guide may include patient specific contours adapted to substantially conform to an unaltered portion of the patient's anatomy. The second portion 814B may generally hook around the patient's anatomy. In this manner, the second portion 814B contacts a different plane of the patient's anatomy compared to portion 814A. Although the guides 810 illustrated in Figs. 11-12 include two slots, it will be appreciated that the guides may include any number of slots. The slots may also have different shapes, including arcuate shapes. Further, the guides 810 may include slots to target both sides of a vertebra. In another embodiment, different guides 810 may be formed to target each of the posterior sides of the vertebrae. In this embodiment, the two guides for each side of the vertebrae may be keyed. The keys enable the guides to be interconnected together during the procedure. In this manner a guide 810 can be assembled that targets both sides of the vertebrae while still protecting neural elements. The keys may optionally be adapted to require a specific assembly sequence of the individual guides. A recess 854 may be formed in a portion of the guides 810. The recess 854 has a cross-sectional shape selected to at least partially wrap around a neural element N, such as the spinal cord, of the patient. In one embodiment, the recess 854 has a shape similar to a "C" or a vaulted ceiling. The recess 854 includes an interior surface 856, illustrated in Fig. 11A, that is spaced from an interior surface of the slots 820. In this manner, the recess 854 protects the neural element N from inadvertent damage as a tool is guided in the slot 820 to form a cut in the vertebrae. Referring now to Fig. 12, guide 810B is similar to guide 810A. Additionally, guide 810B includes a second recess 854A which is shaped to protect a second neural network, N2, such as a nerve root, from damage. Referring now to Figs. 13A-13E, another guide 910 of an embodiment of the present invention is illustrated. Guide 910 is similar to guides 810A, 810B. In one embodiment, the guide 910 is adapted for use to make final cuts 950 required during a pedicle subtraction osteotomy (or APSO). Guide 910 generally comprises a radiused comer 958, a recess 954, and guide slots 920. After portions of the vertebrae have been removed exposing a neural network N, such as the spinal cord, the guide 910 is placed between the spinal cord and the vertebrae VM. The radiused corner 958 of the guide is shaped to push the neural elements to create a space for the guide between the spinal cord and the vertebrae. The neural element N is then received in the recess 954 which protects the neural element from damage during cutting performed using the slots 920 of the guide 910. The guide includes patient-specific features 914 that allow it to fit in a predetermined location. These features may match with the patient's anatomy (the anterior portion of the spinal canal) or may match to the cutting surfaces 950 generated with earlier guides. The slots 920 are similar to slots of all embodiments of guides of the present invention described herein. Further, sleeves may be placed in the slots 920 to prevent damage or alteration of the slots by cutting tools used in the surgical procedure. The slots may align with previously completed cuts. In this manner, new cuts guided by the slots will intersect the previous cuts so that a portion of the vertebrae may be removed. In one embodiment, the slots 920 are aligned to complete a cut to remove a medial portion of the vertebral body. Referring now to Figs. 14-19, embodiments of models of the present invention are illustrated. The models are adapted for use during a surgical procedure, such as an osteotomy, as a reference for the surgeon. The models may be designed with patient specific features and apertures or surfaces aligning with operations to be performed during the surgical procedure. The models include presurgically planned corrections to the patient's anatomy. For example, the models may include indications of angles and starting locations of multiple cuts required to make planned corrections to patient's alignment. The models can include surfaces and indications aligning with cuts of any size and shape, including cuts that are straight, concave, convex, curvilinear, or 'chevron' shaped. Further, the models can be designed to be modular such that separate portions are interconnected to form the finished model during a surgical procedure. This may be beneficial for models designed to fit around, or conform to, portions of the patient's anatomy with complex exterior contours.

Referring now to Figs. 14A-14E, an embodiment of a model 1002 of the present invention is illustrated. The model 1002 is designed to include patient specific surfaces 1014 substantially conforming to a portion of the posterior surface of a vertebrae V. In one embodiment, the model is adapted to at least partially fit around a portion of the vertebrae that is planned to be removed during the surgical procedure. In another embodiment, at least a portion of the model is adapted to substantially conform to, or "hook" to, a predetermined portion of the patient's anatomy, such as the vertebrae. Said another way, the model may be adapted to bias into a predetermined orientation with respect to the patient's anatomy. Accordingly, the material of the model 1002 may be selected to allow a surgeon bend or stretch the model 1002 to hook around the patient's anatomy. In one embodiment, the model 1002, or portions thereof, may be manufactured from a material that is at least partially flexible or deformable. In another embodiment, the model is manufactured from a material with shape memory, such as Nitinol. The model 1002 is adapted to indicate entry points and angles of the planned cuts. In one embodiment, the model includes indicia that indicated the entry points. In another embodiment, at least one exterior surface of the model is parallel to the plane of a planned cut. For example, in the embodiment of the model 1002 illustrated in Fig. 14E, exterior surface 1013 is substantially parallel to the plane of a cut planned to remove the spinous process S. Although not illustrated, the model may include slots and cannula to guide cuts and bores into portions of the vertebrae V. As will be appreciated, the size and shape of the model 1002 may vary as planned to guide any variety of cuts. For example, if the thickness of the model 1002 illustrated in Fig. 14E is increased, less of the spinous process S will be removed by a cut guided by surface 1013. In the alternative, more of the spinous process S can be removed by decreasing the height of the model 1002. Referring now to Figs. 15A-15F, still another model 1102 of the present invention is illustrated. Model 1102 is adapted for use in an asymmetrical pedicle subtraction osteotomy in one embodiment of the present invention. Model 1102 is similar to model 1002. Thus, the model may include indicia and other indications of entry points and angles of cuts. However, model 1102 further includes an aperture 1128 that fits around a portion of the vertebrae planned to be removed. In one embodiment, the aperture 1128 has a shape that is asymmetric around a vertical axis substantially parallel to the shorted sides of the model 1102. The aperture 1128 thus forms a window that indicates the bone intended for removal during the asymmetrical pedicle subtraction osteotomy. In one embodiment, proximal surface 1113 of the model 1102 is about parallel to the plane of a cut planned to remove a predetermined portion of the spinous process S. As will be appreciated, the model 1102 and the aperture 1128 may be of any size and shape. The model also includes a variety of patient matched surfaces 1114 associated with portions of the patient's anatomy similar to the patient specific surfaces 1014 of model 1002. Further, the patient specific surfaces may be formed in voids 1117 formed in the model. The voids are adapted to align the model with the patient's anatomy. The model 1102 may further include projections 1119 with patient specific surfaces 1114 adapted to mate with portions of the patient's anatomy. The combination of voids 1117 and projections 1119 may decrease the possibility of improper placement of the model 1102 in relation to the patient's anatomy.

Figs. 16A-16C illustrate a model 1102A of another embodiment of the present invention. Model 1102A is similar to model 1102. However, the aperture 1128A has a different shape that is substantially symmetric about a vertical axis. The aperture 1128A thus forms a window that indicates the bone intended for removal. As will be appreciated, the model and the aperture 1128A may be of any size and shape. In one embodiment, model 1102A is thicker than model 1102. Accordingly, model 1102A may be designed for a procedure in which less of the spinous process S is planned to be removed compared to a procedure using model 1102. The model 1102A also includes a variety of patient specific surfaces associated with portions of the patient's anatomy similar to the patient specific surfaces 1114 of model 1102. Further, voids and projections may be formed on the model 1102A similar to the voids and projections of model 1102 described above. Referring now to Figs. 17A-17E, still another model 1202 of an embodiment of the present invention is illustrated. The model 1202 generally comprises a first portion 1208 and a guide portion 1210. In one embodiment, the first portion and the guide portion are integrally formed as one piece. In another embodiment, portions 1208, 1210 are individual pieces adapted to be interconnected before or during a surgical procedure. The features 1260, 1262 are provided to align and interconnect the guide portion 1210 to the first portion 1208. In one embodiment, the features comprise projections 1260 formed on one of the portions adapted to be retained in bores 1262 formed in the other portion. Although the projections are illustrated on the guide portion 1210 and the bores are illustrated on the first portion 1208, it will be appreciated the guide portion and the first portion may each comprise projections and corresponding bores. Further, other features adapted to interconnect and/or align portions 1208, 1210 are contemplated and may be used with the model 1202. The first portion 1208 is similar to models 1002-1102 described above. Accordingly, the first portion generally includes patient specific surfaces 1214, voids 1217, protrusions 1219, and an aperture 1228 that are the same as (or similar to) the corresponding features of other models and guides described herein. The guide portion 1210 generally includes tracks 1220 for guiding cutting tools, similar to the slots of all embodiments of the guides described herein. Thus, the tracks 1220 may be of any size and shape. Additionally, the tracks may be sized to receive sleeves and may include stops and keys to guide a direction of use of the cutting tool or limit the depth of insertion of the tool. Further, the tracks 1220 may have an asymmetric alignment. Referring now to Figs. 18-19, still more embodiments of models 1302A, 1302B of the present invention are illustrated. The models are adapted to dock to a frame 1330. The frame 1330 may be the same as, or similar to, frames 330, 730 described above. Accordingly, models 1302 are adapted to fit with either pre-existing or planned pedicle screws 1334. The models may optionally contact a surface 1350 of the medial vertebrae VM prepared in a previous cutting procedure. The models 1302A, 1302B generally include apertures 1328 and voids 1317 for interconnection to the frame. In one embodiment, the model 1302A includes a closed aperture 1328. Accordingly, the model 1302A is generally interconnected to a medial portion of the frame 1330 before the frame is interconnected to the pedicle screws 1334. Further, the models may include a recess 1354 similar to recess 854, 954 described above. The recess has a cross-sectional shape similar to at least partially wrap around a neural element, including the spinal cord of the patient. The models may also include indicia that indicate a location to begin a cut and an angle of the cut. Model 1302A is generally comprised of two portions 1307A, 1307B. Each portion includes a leg or medial surface 1309 that indicates an angle of a planned cut. For example, medial surfaces 1309 are generally in a plane that is parallel to a place formed by a planned cut into the vertebrae. Thus, the space between portions 1307A, 1307B generally indicates the shape of a portion of the vertebrae VM that will be removed. In one embodiment, the medial surface 1309 includes a distal portion with patient specific contours 1314. The patient specific contours may substantially conform to a cut portion 1350 of the patient's anatomy. Optionally, the distal portion of medial surface 1309 may be adapted to contact and substantially conform to an uncut portion of the patient's anatomy. In contrast, model 1302B comprises one piece. Angles of planned cuts are indicated by legs or exterior surfaces 1309 of the model 1302B proximate to the superior and inferior vertebrae VS, VI. Accordingly, the shape of the model generally indicates the shape of a portion of the vertebrae VM planned for removal. In addition, model 1302B has a void 1317 with an opening for interconnection to the frame 1330. Accordingly, the model 1302B may be added and removed from the frame without disassembling the frame 1330. In one embodiment, distal portions of the surface 1309 include patient specific contours 1314.

Referring now to Figs. 20A-20F, still another embodiment of a model 1402 of an embodiment of the present invention is illustrated. Model 1402 is a patient specific three dimensional model of grouping of vertebrae of the patient. The model is created for use in planning and performing a surgical procedure that includes removal of a section 1405 of the patient's spine. In one embodiment, the model is adapted for a spinal osteotomy procedure. The section 1405 of the spine to be removed during the surgery is formed as a separate piece from other portions of the model. A handle may be interconnected to the removable section 1405. In this manner, the removable section 1405 may be separated from, or returned to, a position in the model 1402. The removable section 1405 may be used as a template or measurement jig during surgery. A portion of the removable section 1405A could be cut away to avoid contact with neural elements of the patient during surgery, as illustrated in Fig. 20C. The removed portion may conform to portions of the vertebrae of the patient removed during the surgery. Thus, the distal end of the modified section 1405A can be adapted to substantially align with surfaces of the target vertebrae. The superior VS and inferior VI portions of the spine may also be formed as separate pieces. Thereafter the superior and inferior portions may be interconnected. In one embodiment, spine portions VS, VI are interconnected by a hinge 1464. However, it will be appreciated by one of skill in the art that other means may be used to interconnect the superior and inferior spine portions. For example, in another embodiment, a flexible member can be used to interconnect spine portions VS, VI. In another embodiment, a ball and socket joint may be provided to interconnect the spine portions VS, VI. After the removable section 1405 of the model is withdrawn, the superior and inferior spine portions VS, VI can be repositioned, as illustrated in Fig. 20D, to demonstrate the corrected alignment of the spine provided by the procedure. The model 1405 may indicate that different, or additional, procedures will be required to correct a spinal abnormality. To further visualize the alignment of the patient's spine before and after the planned procedure, indicators 1466A, 1466B may be interconnected to the superior and inferior spine portions VS, VI, respectively, as illustrated, for example, in Figs. 20E-20F. In one embodiment, the indicators 1466 comprise rods with a curvilinear shape. It will be appreciated that the indicators may comprise different forms. The indicators simulate how the sagittal alignment of the patient's spine is altered by the pre-surgically planned osteotomy angles. A variety of patient specific verification tools, illustrated in Figs. 21-24, can be pre-operatively planned and manufactured in order to aid in verifying final sagittal and/or coronal alignment and/or confirm screw placement. The verification tools are unique to each patient and may contain patient matching surfaces, implant contacting surfaces, and/or capability to mate with a guide. The verification tools of the present invention described in conduction with Figs. 21-24 offer visual or tactical feedback to the surgeon during or after a surgical procedure. Referring now to Figs. 21-22, tools 1501A, 1501B of embodiments of the present invention are illustrated. The tools are adapted to verify coronal alignment during a surgical procedure. Said another way, the tools 1501 are used by a surgeon to verify that planned correction of the spine was substantially generated. The tools 1501A, 1501B are designed using patient specific data and may be manufactured by any method. The tools 1501 generally comprise armatures 1570 extending from a medial body 1572. The medial body 1572 simulates a planned coronal alignment. Some of the armatures may be interconnected to portions of the patient's anatomy. In one embodiment, illustrated in Figs. 21A-21D, the armatures may be interconnected to pedicle screws positioned in at least one of the ilium and the sacrum. In another embodiment, the tool 1501B is interconnected to only the sacrum. The screws may be from a previous procedure or placed specifically to interconnect the tools 1501 to the patient's anatomy. Optionally, in another embodiment, the medial body 1572 includes patient specific contact surfaces selected to substantially match the posterior surface of the sacrum. Thus, the medial body 1572 may be retained on the sacrum with or without the use of pedicle screws. An armature 1570A may be adapted to extend from the medial body to one or more superior vertebrae. The armature 1570A may have a non-linear shape adapted to substantially align with predetermined portions of the superior vertebrae when the planned correction of the spine is generated. In one embodiment, the armature 1570A is adapted to align with a posterior portion of the spinous processes S of number of superior vertebrae. Optionally, the armature 1570A may contact portions of the superior vertebrae when the planned correction is generated. In one embodiment, the tool 1501A comprises five armatures 1570 extending from the medial body 1572. In another embodiment, the tool 1501B includes three armatures 1570 extending from the medial body. In another embodiment, the tool 1501 includes an electronic alignment indicator. The electronic indicator may comprise a light source or a laser aligned to produce a visible beam indicating the planned position of one or more vertebrae. The electronic indicator may be positioned in the medial body or on an armature. Yet another embodiment of a tool 1601 of an embodiment of the present invention is illustrated in Figs. 23A-23E. The tool 1601 is similar to tools 1501 and is also used to verify coronal alignment during a surgical procedure. The tool generally comprises an armature 1670 interconnected to a guide 1646. In one embodiment, the armature 1670 extends from a medial body 1672 of the guide. The medial body 1672 may include a fixture for interconnecting the armature 1670 to the guide 1646. The guide may be a sacroiliac guide. In one embodiment of the present invention, the guide 1646 is similar to guide 246 described above. Alternatively, in another embodiment, the guide 1646 is one of the guides described hereinafter in conjunction with Figs. 25-31. The armature 1670 may be integrally formed with the guide 1646. Optionally, the armature and the guide may be formed as separate pieces and interconnected before or during the surgical procedure. The curvilinear shape of the armature 1670 is adapted to indicate the planned sagittal and coronal alignment of patient's spine after the surgical procedure is completed, as illustrated in Figs. 23D-23E. Similar to armature 1570A described above, the armature 1670 has a length selected to extend proximate to a number of superior vertebrae. The armature may have a shape that is proximate to, or contacts, portions of a number of vertebrae. Referring now to Figs. 24A-24B an embodiment of an alignment assembly 1700 of an embodiment of the present invention is illustrated. The assembly 1700 generally comprises armatures 1770 interconnected to a medial body 1772. The medial body may have a predetermined shape and size. In one embodiment, the medial body 1772 has an arcuate shape. The medial body 1772 includes indicia 1774 that indicate a relative alignment of the patient's vertebrae, such as interior VI and superior VS vertebrae proximate to medial vertebrae VM. The indicia may comprise a series of lines that optionally are graduated to indicate predetermined angles or distances. The medial body 1772 may be an existing tool, such as the scale of a protractor or a ruler. In one embodiment, the indicia 1774 include projections 1776 indicating a planned correction.

At least one of the armatures 1770 is moveably interconnected to the medial body 1772. In one embodiment, the armatures 1770 include a proximal portion forming a pointer. The pointer 1771 indicates the position of the armature on the indicia of the medial body 1772. A distal portion of each armature is interconnected to fixtures (not illustrated) placed in vertebrae of the patient. The fixtures may comprise pedicle screws. Optionally, the armatures 1770 may have features adapted to be received directly in a cannula formed in vertebrae. In one embodiment, one armature 1770 is interconnected an inferior vertebrae VM and a second armature is interconnected to a superior vertebrae VS. However, other interconnection locations of the armatures are contemplated. For example, in one embodiment of the present invention, one of the armatures 1770 is interconnected to a portion of the medial vertebrae VM. In use, the alignment assembly 1700 may provide a first reading before the alignment of the spine is altered, as shown in Fig. 24A. After cuts 1750 are formed in the medial vertebrae VM, the alignment of the superior and inferior vertebrae VS, VI can be altered, drawing two cuts edges 1750 of the medial vertebrae VM closer together. A second reading of the alignment of the spine is then provided by the alignment assembly 1700, as shown in Fig. 24B. Referring now to Figs. 25-26 in detail, a patient-specific guide 1810 of an embodiment of the present invention is illustrated. The guide 1810 may comprise a spanning member or medial body 1812, arms 1814, a cannulae 1816, and a patient matched leg 1824. In one embodiment of the present invention, the guide 1810 includes two arms 1814, two cannulae 1816, and two legs 1824. However, the guide 1810 of the present invention may include any number of cannulae and legs. The cannulae 1816 and legs 1824 may all have different lengths. Additionally, the angle and orientation of each cannulae and leg can be varied to match the anatomy of the patient, or to avoid a portion of the patient's anatomy. In one embodiment of the present invention, the cannulae 1816 have a generally cylindrical shape. Although the guide 1810 illustrated in Figs. 25-26 generally shows the cannulae 1816 and legs 1824 interconnected with two arms 1814, one of skill in the art will appreciate that the cannulae 1816 and legs 1824 may be interconnected in any number of ways. For example, in one embodiment, the cannulae 1816 may be interconnected by a curved medial body. Optionally, in one embodiment, the cannulae 1816 and legs 1824 may be formed as separate pieces that are individually located with respect to the patient's anatomy and then interconnected during the surgical procedure. The cannulae 1816 are configured to contact one or more of the lamina, pars interarticularis, and aspects of the transverse process and the superior articular process of the patient. Cutouts 1817 may optionally be formed on a portion of the cannulae 1816 to prevent the guide 1810 from contacting the spinous process of the patient, or to avoid other patient anatomy. In alternate embodiments, cutouts 1817 may comprise one or more patient-matched surfaces or features for contacting in a complementary fashion the surrounding patient anatomy. In certain embodiments, cutouts 1817 may be oriented to achieve greater visibility to the surgeon/user, or to facilitate placement of one or more instruments or other devices as described herein. In further alternate embodiments, cutouts 1817 are not provided with the cannulae. In one embodiment, the cutouts 1817 may be adapted to provide a patient specific contour to match the spinous process or other unique patient anatomical feature and provide yet another surface for ensuring alignment and seating of the guide. The cannulae may include a generally hollow bore 1820 adapted to guide instruments and fixation devices in the cortical trajectory. The bore 1820 of each cannulae 1816 can have an internal diameter that corresponds to a particular instrument or fixation device to prevent the use of the incorrect instrument or device. Thus, the dimensions of the bores of two cannulae may be different. The internal diameter of the bore 1820 may be selected to prevent the instrument or device from advancing into the cannulae 1816 beyond a predetermined distance, thereby providing a hard stop. Alternatively, a protrusion, key, notch, or void may be formed on the cannulae or in the bore to one or more of: prevent the use of the incorrect instrument or device; prevent an incorrect orientation of the correct tool or device; and prevent over insertion of the tool or device. Further, the cannulae 1816 may have a varying length and may be made longer or shorter depending on the geometry of the cannulae 1816, the patient's anatomy, the purpose of the guide 1810, etc. For example, if a greater depth of a particular instrument or fixation device is required, the cannulae 1816 may be shorter to accommodate further penetration of the instrument or fixation device into patient's vertebrae.

The guide 1810 may include a patient-matched leg 1824 adapted to contact predetermined portions of the patient's anatomy. In one embodiment, the leg 1824 contacts one or more of the inferior articular process, lamina, and the transverse process.

Optionally, the guide may include two or more legs. In one embodiment, the leg comprises a distal portion 1824A and a proximal portion 1824B. As will be appreciated, the legs 1824 may also extend from the cannulae 1816. For example, in one embodiment, the leg comprises only a distal portion 1824A extending from the cannula 1816. Additionally, or alternatively, patient-specific contact surfaces 1818, 1826 may be formed on any patient-contacting surfaces of the cannulae 1816 and/or the legs 1824, respectively. The surfaces 1818, 1826 provide a plurality of patient-specific contours for matching with a plurality of anatomical features. Further, the lower, patient-contacting surfaces 1818, 1826 may comprise dynamic contours having multiple compound radii. Accordingly, the surfaces 1818, 1826 are substantially congruent with the corresponding anatomical features of the vertebrae or other anatomical feature of the patient. Further, the surfaces 1818, 1826 may contact or protrude around one or more of, but not limited to, the group comprising: the medial side of the inferior articular process, the lateral sides of the lamina, the junction between the pars and the transverse process, and other anatomical features of the patient. The guide 1810 may further comprise slots 1830 formed in the medial body 1812, arms 1814, cannulae 1816, or the legs 1824. The slot 1830 may be a cutting slot to direct the path of a blade or other cutting instrument as will be appreciated by one of skill in the art. In other embodiments, the slot 1830 may be adapted to receive a measurement aid or tool for facilitating the surgeon/user in identifying landmarks, surrounding boney anatomy, placement of implanted devices, or for surgical planning. Alternatively, the slot 1830 may be adapted to receive one or more secondary or tertiary cannulae 1840, 1850 as further described in conjunction with Fig. 31. In certain embodiments, the tertiary cannulae 1840, 1850 may further comprise a patient-matched surface or feature for contacting a particular patient anatomical surface or feature. In alternate embodiments, the tertiary cannulae are generally smooth and do not comprise patient-matched surfaces or features.

Referring now to Figs. 27A-C, another patient-specific guide 1910 of an embodiment of the present invention is illustrated. The guide 1910 comprises a medial body 1912 and at least one cannulae 1916. In one embodiment, the guide 1910 is formed as two separate pieces that may be individually positioned in contact with a predetermined feature of the patient's anatomy and then interconnected during the surgical procedure. The two portions 1912A, 1912B of the medial body are adapted be interconnected. In one embodiment, the medial body 1912B includes a coupling 1913 adapted to releasably interconnect the individual pieces of the guide 1910 together. Accordingly, in one embodiment, the two portions of the guide may be interconnected by positioning the coupling 1913 in a corresponding void in medial body 1912A. The coupling may be held in the void by friction. Additionally, or alternatively, a biasing force may be provided to retain the coupling 1913 in the void. In one embodiment, the coupling and void comprise a snap. In another embodiment, the medial body may include magnets. Optionally, in still another embodiment, the medial body portions 1912A, 1912B may be interconnected by a flexible or expandable member, such as a hinge or a biasing member of any type, including a spring. It will be appreciated by one of skill in the art that the medial body portions 1912A, 1912B may be interconnected by any other suitable means. Optionally, in another embodiment of the present invention, the guide 1910 is formed as one integral piece. The cannulae 1916 are the same as or similar to the cannulae 1816 described above in conjunction with Figs. 25-26. In one embodiment, the cannulae 1916 has a generally cylindrical shape. In like manner, the cannulae 1916 are configured to contact one or more of the patient's lamina, pars, and aspects of the transverse process and the superior articular process or other portions of the patient's anatomy. The cannulae may be formed without a bore. In another embodiment, the cannulae 1916 may include a bore 1920 similar to bore 1820. The bore 1920 comprises a predetermined internal diameter that is adapted to receive a particular instrument or fixation device to prevent the use of the incorrect instrument or device. The internal diameter of the bore 1920 may be selected to prevent the instrument or device from advancing into the cannulae 1916 beyond a predetermined distance, thereby providing a hard stop. Additionally, the bore 1920 may have a shape adapted to align the tool or fixation device in a predetermined orientation of use. Further, the cannulae may be of any length based at least in part on the specific patient's anatomical features, preferences of the surgeon, orientation of the guide 1910, and the type of tool or fixation device associated with the cannulae 1916. Additionally, or alternatively, patient-specific contact surfaces may be formed on any patient-contacting surfaces 1918 of the cannulae 1916 and/or the contacting surfaces 1926 of the medial body 1912. The surfaces 1918, 1926 provide a plurality of patient specific contours for matching with a plurality of anatomical features, as described in greater detail above. The surfaces 1926 of the medial body 1912 may contact at least the front of the spinous process S. The surfaces 1918 of the cannulae 1916 are adapted to contact or protrude around one or more of, but not limited to, the group comprising: the medial side of the inferior articular process, the lateral sides of the lamina, the spinous process, and the junction between the pars and the transverse process, and other anatomical features of the patient. These patient-contacting surfaces 1918, 1926 help position the guide 1910 and keep it in position in a predetermined position and orientation. Referring now to Figs. 28A-B, a patient-specific guide 2010 of still another embodiment of the present invention is illustrated. The guide 2010 generally comprises a cannulae 2016 and one or more legs 2024. The cannulae 2016 are the same as or similar to the cannulae described above in conjunction with Figs. 27-28. Although only one cannula 2016 is illustrated in Fig. 28, one of skill in the art will appreciate that the guide 2010 may have any number of cannulae. The cannulae 2016 includes a bore 2020, the same as or similar to bores 1820, 1920, which comprises a predetermined internal diameter to receive a particular instrument or fixation device. Accordingly, the bore 2020 may prevent the use of the incorrect instrument or device and prevent to incorrect use of the instrument or device. Thus, the internal diameter of the bore, the shape of the bore, and/or a feature formed on or in the bore may be selected to prevent the instrument or device from advancing into the cannulae 2016 beyond a predetermined distance, thereby providing a hard stop. The length of the cannulae 2016 may also be increased or decreased based at least in part on the instrument or device associated with the cannulae 2016, the orientation of the guide with respect to the patient's anatomy, and preferences of the surgeon. Thus, the cannulae may be adapted to prevent the instrument or fixation device from advancing too far into the boney anatomy of the patient. Additionally, or alternatively, the cannulae 2016 may include a second bore. The second bore may be oriented in a different trajectory for placement of a temporary fixation device. Optionally, the cannulae may include a track or slot adapted to guide an instrument operable to remove a predetermined portion of a vertebrae. The slot may include patient-specific depth control, angle control, and orientation. The slot may be the same as, or similar to, any of the slots described herein such as slots 20, 120, 320, 420, 520,720,820,or1220. In one embodiment of the present invention, the cannulae 2016 has a length such that the distal or terminal end 2018 of the cannulae 2016 does not contact the patient's anatomy. Said another way, the terminal end 2018 of the cannulae 2016 is adapted to float above a predetermined portion of the patient's anatomy. In another embodiment of the present invention, the cannulae 2016 has a different length such that the terminal end 2018 of the cannulae 2016 intentionally contacts a predetermined portion of the patient's anatomy. Continuing this example, patient-specific contact surfaces may be formed on the terminal end 2018 of the cannulae 2016. Thus, the terminal end 2018 of the cannulae 2016 may optionally provide still another guide surface to align and/or stabilize the guide 2010 in a predetermined orientation during a surgical procedure. The legs 2024 of the guide 2010 may each comprise a different length. Additionally, the position and alignment of the legs 2024 with respect to the cannula 2016 may vary based on patient specific anatomical features, a planned orientation of the guide 2010, or a preference of the surgeon. The legs 2024 are adapted to contact predetermined portions of the patient's anatomy. In one embodiment, one or more of the legs 2024 may be adapted at least partially conform to, or hook around, a predetermined portion of the patient's anatomy. Accordingly, the guide 2010, or portions thereof, may be made of a material selected to allow a surgeon bend or deform the guide 2010 to fit around the patient's anatomy. In one embodiment, the legs 2024, or portions thereof, are manufactured from a material that is at least partially flexible or deformable. In another embodiment, at least a portion of the legs 2024 are manufactured from a material with shape memory, such as Nitinol. Accordingly, the legs may provide a bias force to releasably retain the guide 2010 in a predetermined alignment with respect to the patient's anatomy. Accordingly, in one embodiment, at least one of the legs includes a curved shape, or a cutout similar to cutouts 1817 described above in conjunction with Figs. 25-26, to prevent unintended or inadvertent contact between the guide 2010 and the spinous process S or another anatomical feature of the patient. Alternatively, in another embodiment, at least one of the legs may include a curved shape or cutout with patient-matched surfaces adapted to create still another patient specific contact surface to one or more of align and stabilize the guide 2010. In one embodiment, at least one of the legs 2024 contacts one or more of the group comprising the inferior articular process, lamina, superior articular process, the transverse process, and another anatomical feature. The terminal ends 2026 of the legs 2024 may include patient-specific contact surfaces the same as or similar to contact surfaces 1826, 1926 described above in conjunction with Figs. 25-27. Additional patient specific contact surfaces may also be formed on one or more other surface of the legs 2024.

Referring now to Figs. 29A-C, another patient-specific guide 2110 of another embodiment of the present invention is illustrated. The guide 2110 generally comprises a medial body 2112 and at least one cannulae 2116. The medial body 2112 comprises a distal surface 2113 adapted to contact predetermined portions of the patient's anatomy. In one embodiment, the distal surface 2113 is adapted to contact one or more of the group comprising the inferior articular process, lamina, spinous process, pars, the transverse process, and other features of the patient's anatomy. Thus, the distal surface 2113 of the medial body 2112 provides a patient specific surface to align the guide 2110 in a predetermined orientation. Optionally, one or more of the lateral surfaces 2111 may have patient specific shapes adapted to contact, or interconnect to, other portions of the patient's anatomy. For example, the guide 2110 may include extensions or legs, similar to legs 2024, adapted to hook around, portions of the patient's anatomy. The legs may be made of a flexible or deformable material, including Nitinol. In one embodiment, the legs are adapted to provide a bias force to "hook" the guide in a predetermined orientation with respect to the patient's anatomy. Further, the surface 2113 may comprise two or more surface portions 2113A, 2113B adapted to contact different portions of the patient's anatomy. Accordingly, the surfaces 2111, 2113A, 2113B can form a complex shape selected to provide a substantially tight fit of the guide 2110 to the patient's anatomy to one or more of: prevent unintended or inadvertent movement of the guide 2110 during the surgical procedure and position the guide 2110 in a predetermined position with respect to the patient's anatomy. The distal surface 2113 may further include a relief portion 2115 to prevent unnecessary contact with the patient's anatomy to avoid unnecessary or unintended tissue dissection or damage. Optionally, one or more of the surfaces 2111, 2113A, 2113B may have a shape or protrusion adapted to displace soft tissue. The cannula 2116 is the same as or similar to the cannulae described above in conjunction with Figs. 25-28. One of skill in the art will appreciate that the guide 2110 may have any number of cannulae. In one embodiment of the present invention, the guide 2110A includes two cannulae 2116, 2116A. Further, the cannulae may each have a different orientation to target different portions of the patient's anatomy. The cannulae generally pass from the proximal surface of the guide 2112 to the distal surface 2113. Further, although illustrated protruding from the proximal surface of the guide 2112, one of skill in the art will appreciate that the cannula 2116 may terminate at a point substantially level with the proximal surface of the guide. Additionally, the cannula may have any predetermined orientation with respect to the medial body 2112 of the guide 2110. In one embodiment, the cannula has an orientation that passes through the proximal surface and the distal surface of the guide. In another embodiment of the present invention, at least one end of the cannula 2116A passes through a lateral surface 2111 of the guide 2110. The cannulae 2116, 2116A include a bore 2120 similar to bores 1820, 1920, 2020. The bore 2120 comprises a predetermined internal diameter or shape to receive a particular instrument or fixation device. Accordingly, the bore 2120 may prevent the use of the incorrect instrument or device. The bore 2120 may also be adapted to prevent the improper use of an instrument or device. Thus, the internal diameter or the shape of the bore 2120 may be selected to prevent the instrument or device from advancing into the cannulae 2116 beyond a predetermined distance, thereby providing a hard stop. In this manner the cannulae may be adapted to prevent the instrument or fixation device from advancing too far into the boney anatomy of the patient. During a surgical procedure, two or more guides 2110 may be used. As illustrated in Fig. 29C, each guide may be positioned in contact with different portions of the patient's anatomy. Further, although not illustrated in Fig. 29, the individual guides 211OB, 211OC can be interconnected together before or during the surgical procedure. Accordingly, in one embodiment of the present invention, guides 211OB, 211OC include a structure similar to the medial body 1912 described above in conjunction with Fig. 27 adapted to releasably interconnect the guides together. In another embodiment, the guides 211OB, 211OC include a structure similar to the arm 1814 to permanently interconnect the guides together. In one embodiment, the guide 2110 may be interconnectable to a frame similar to guide 2010. Accordingly, the guide 2110 may be used with one or more frames 330, 730, 1330 before, or after, one or more of guide 310, 710, 1302, and 2010. Referring now to Figs. 30A-C, a patient-specific guide 2210 of yet another embodiment of the present invention is illustrated. The guide 2210 generally comprises a medial body 2212, a cannulae 2216, one or more legs 2224, and a second leg or bridge 2230. The cannulae 2216 may be the same as or similar to the cannulae described above in conjunction with Figs. 25-29. Although two cannulae 2216 are illustrated in Fig. 30, it will be appreciated by one of skill in the art that the guide 2210 may have any number of cannulae. Further, each cannulae 2216 has a predetermined length that may be shorter or longer than the length of a different cannulae of the guide. The cannulae 2216 may include a bore 2220 similar to bores 1820, 1920, 2020, 2120. The bore 2220 comprises a predetermined internal diameter adapted to receive a particular instrument or fixation device. Accordingly, the bore 2220 may prevent the use of the incorrect instrument or device. The shape and/or the internal diameter of the bore 2220 and the length of the cannulae 2216 may be selected to one or more of: prevent the instrument or device from advancing into the cannulae 2216 beyond a predetermined distance, prevent the use of the incorrect instrument or device, and ensure proper alignment and use of the correct instrument or device. Although illustrated in Fig. 30 as having a generally linear shape, it will be appreciated by one of skill in the art that one or more of the legs 2224 may have a curvilinear shape. Thus, the shape, length, and orientation of the legs may be customized to contact predetermined portions of the patient's anatomy while avoiding contact with other features of the patient's anatomy. Accordingly, in one embodiment, at least one of the legs includes a curved shape, or a cutout similar to cutouts 1817 described above in conjunction with Figs. 25-26, to prevent unintended or inadvertent contact between the guide 2210 and the spinous process, the lamina, or another anatomical feature of the patient. Alternatively, in another embodiment, at least one of the legs 2224 may include a curved shape or cutout with patient-matched surfaces (similar to surfaces 1926 described above in conjunctions with Fig. 27) adapted to create other patient specific contact surfaces to one or more of align and stabilize the guide 2210. In one embodiment, at least one of the legs 2224 contacts one or more of the group comprising the inferior articular process and the lamina. The terminal ends 2226 of the legs 2224 may include patient-specific contact surfaces the same as or similar to contact surfaces 1826 described above in conjunction with Figs. 25-26. Additional patient specific contact surfaces may also be formed on one or more other surface of the legs 2224. Although not illustrated, the contact surfaces 2226 may include protrusions adapted to one or more of: align the guide 2210 in a predetermined position with respect to the patient's anatomy, prevent unintended or inadvertent movement of the guide 2210 during a surgical procedure, and displace soft tissue. In one embodiment, the contact surfaces 2226 comprise relatively thin extensions. The second legs or bridge 2230 is adapted to contact one or more of the spinous process S and the lamina of the patient. In the embodiment of the present invention illustrated in Fig. 30, the bridge 2230 extends medially from the cannulae 2216. In another embodiment, the bridge 2230 extends medially from the legs 2224. The bridge 2230 may be formed as a single piece and include a longitudinal cavity. In this manner, the longitudinal cavity is adapted to substantially mate with the contours of a predetermined portion of the patient's anatomy. In one embodiment, the longitudinal cavity is adapted to contact the contours of the spinous process S of a particular vertebral body V of the patient. In another embodiment, the bridge 2230 is formed of two separate portions 2230A, 2230B. In all embodiments of the present invention, the bridge 2230 may include one or more contact surfaces 2234 adapted to mate with the contours of one or more of the spinous process, the lamina, and other anatomical features. Thus, the bridge 2230 facilitates one or more of ensuring a predetermined alignment of the guide 2210 and preventing inadvertent or unintended movement of the guide 2210 during a surgical procedure. The guide 2210 may also include extensions adapted to hook at least partially around, or to, a portion of the patient's anatomy. For example, in one embodiment of the present invention, one or more of the medial body 2212, the legs 2224, and the bridge 2230 may have a shape adapted hook to the patient's anatomy. In another embodiment, a portion of the guide 2210, such as one of the legs, medial body, or the bridge, may comprise a flexible or bendable material as previously described. In use, a surgeon may bend or alter the guide 2210 to hook to the patient's anatomy. As will be appreciated, the guide 2210 may also include a cutting guide 10. The cutting guide 10 may be interconnected to any portion of the guide 2210, similar to the cutting guide 10 illustrated in Fig. 27D. Referring now to Fig. 31, still another embodiment of a patient-specific guide 2310 of an embodiment of the present invention is illustrated. Guide 2310 is substantially the same as guide 1810 described above in conjunction with Figs. 25-26. Accordingly, the guide 2310 may comprise a medial body 2312, arms 2314, cannulae 2316, and patient matched legs 2324 the same as (or similar to) body 1812, arms 1814, cannulae 1816, and patient-matched legs 1824 of guide 1810. In one embodiment of the present invention, the guide 2310 includes two arms 2314, two cannulae 2316, and two legs 2324. However, the guide 2310 of the present invention may include any number of cannulae and legs. The cannulae 2316 and legs 2324 can each have different lengths. Additionally, the angle and orientation of each cannulae and legs can be varied to match the anatomy of the patient. The guide 2310 may further comprise slots 2330 formed in one or more of the medial body 2312, arms 2314, cannulae 2316, and the legs 2324. The slots 2330 may be cutting slots to direct the path of a blade or other cutting instrument as described above. Alternatively, the slots 2330 may be adapted to receive one or more secondary 2340 or tertiary cannulae 2350. The secondary and tertiary cannulae 2340, 2350 may be positioned in the slots 2330 to target a predetermined portion of one or more of a second level and a third level anatomical feature of the patient. In one embodiment, the cannulae 2340, 2350 are adapted to target one or more predetermined portions of the cervical spine (i.e., Cl-Si and ilium). The cannulae 2340, 2350 include a bore 2320 the same as or similar to bores 1820, 1920, 2020, 2120, and 2220 described above in conjunction with Figs. 25-30. Accordingly, the bore 1820 can guide one or more of a guide wire, a drill bit, a tap, a fixation device (such as a screw), and other instrumentation, including without limitation, tools for harvesting bone grafts. Further the bore and/or the cannulae 2340, 2350 may have a length, shape, protrusion, and/or a diameter selected to prevent the use of the improper tool or device, prevent improper use of a predetermined tool or device, and ensure proper use of the predetermined tool or device. Optionally, in another embodiment of the present invention, the secondary and tertiary cannulae 2340, 2350 may include a track or slot. The slot may be adapted to guide an instrument operable to remove a predetermined portion of a vertebrae. The slot may include patient-specific depth control, angle control, and orientation. In one embodiment of the present invention, the slot of the cannulae 2340, 2350 is the same as, or similar to, any of the slots described herein. For example, the cannulae 2340, 2350 may include a slot similar to slots 20, 120, 320, 420, 520, 720, 820, or 1220. The ends of the cannulae 2340, 2350 may include patient specific contact surfaces as previously described in conjunction with Figs. 25-30. Additionally, the angle and orientation of each cannulae 2340, 2350 can be varied to match the anatomy of the patient. The tertiary cannula 2350 may be releasably interconnected to a secondary cannula 2340. The cannulae 2340, 2350 may be releasably interconnected to the guide 2310 before or during a surgical procedure. The cannulae 2340, 2350 may include an extension 2344 or multiple extensions 2344A to engage the slots 2330 formed on the guide 2310. Each of the slots 2330 may have a different shape, width, depth, and orientation adapted to receive a predetermined cannulae 2340, 2350 in a specific orientation. Alternatively, in one embodiment, the cannulae 2340, 2350 are formed with the guide 2310 as one integral piece.

Referring now to Figs. 32A-B, yet another patient-specific guide 2810 of an embodiment of the present invention is illustrated. In one embodiment, guide 2810 comprises a medial body 2812, at least one cannulae 2816, and a leg 2824. The cannula 2816 may be the same as, or similar to, the cannulae 1816 described above in conjunction with Figs. 25-26. Optionally, the cannula 2816 may be configured to contact one or more of the lamina, pars interarticularis, aspects of the transverse process, the interior articular process, and the superior articular process of the patient. Cutouts (not illustrated) may be formed on a portion of the cannulae 2816 to prevent the guide 2810 from contacting the spinous process of the patient, an adjacent vertebrae, or to avoid other patient anatomy. In one embodiment, the guide 2810 comprises two cannulae 2816; however, it will be appreciated that the guide 2810 may include any number of cannulae. The cannulae 2816 may have a generally cylindrical shape but other shapes are contemplated. Each of the two cannulae 2816 may have a unique orientation and size. The cannulae may be of any length based at least in part on the specific patient's anatomical features, preferences of the surgeon, orientation of the guide 2810, and the type of tool or fixation device associated with the cannulae 2816. The length of the cannulae 2816 may also be selected to provide depth control of instruments guided by the cannulae 2816. The cannulae 2816 may optionally include extensions 2819 of any size or shape. In one embodiment, the extensions 2819 are positioned proximate to a distal end of the cannulae 2816. In another embodiment, the extensions 2819 wrap at least partially around the exterior of the cannulae 2816. The extensions 2819 may also project at least partially beyond the distal end of the cannulae 2816. The extensions are adapted to wrap at least partially around a predetermined portion of the patient's anatomy. In one embodiment, the extensions 2819 are adapted to wrap around a portion of one of the pars and the superior articular process. Optionally, the guide 2810 may include one or more legs 2824. The legs may extend from one or more of the medial body 2812 and the cannulae 2816. The angle and orientation of each leg 2824 with respect to the medial body 2812 may be varied to match the anatomy of the patient, or to avoid a portion of the patient's anatomy. In one embodiment, at least a portion of the medial body 2812, the cannula 2816, and the legs 2824 are configured to contact the patient's anatomy. For example, patient specific contact surfaces 2818, 2825 may be formed on one or more of the cannula 2816, including the projections 2819, and one or more of the legs 2824, respectively. Optionally, at least a portion of the medial body 2812 may be configured to contact a portion of the patient's anatomy. Accordingly, the medial body 2812 may also optionally include patient specific contact surfaces 2826. The contact surfaces 2818, 2825, 2826 may be adapted to fit directly to aspects of the patient's anatomy, such as one or more of the medial side of the inferior articular process, the lateral sides of the lamina, the spinous process, and the junction between the pars and the transverse process, and other anatomical features of the patient. The patient specific contact surfaces 2826 of the medial body 2812 may optionally contact at least a portion of the spinous process. The contact surfaces 2818, 2825, 2826 are determined to match at least a portion of a curvature of the patient's anatomy to facilitate placement of the guide 2810 in a predetermined alignment with respect to a predetermined portion of the patient's anatomy during a surgical procedure. The patient contact surfaces 2818, 2825, 2826 may include any number of protrusions, depressions, and contours to substantially conform to the patient's anatomy. For example, the contact surfaces 2818, 2825, 2826 may comprise multiple portions that are adapted to contact two different planes formed by two distinct portions of the patient's anatomy. In this manner, the contact surfaces 2818, 2825, 2826 are adapted to one or more of: align the guide 2810 in a predetermined position and orientation with respect to the patient's anatomy; hook around a portion of the patient's anatomy; prevent unintended or inadvertent movement of the guide 2810 during a surgical procedure; and displace soft tissue. In one embodiment, the contact surfaces 2818, 2825, 2826 comprise relatively thin extensions to displace soft tissue. By protruding at least partially around and substantially conforming to different portions of the patient's anatomy, the contact surfaces 2818, 2825, 2826 generally "hook" at least partially around (or to) the patient's anatomy. Thus, the surfaces 2818, 2825, 2826 may contact at least two different planes formed by distinct surfaces of the patient's anatomy. At least one of the cannulae 2816 may include a bore 2820 to guide instruments and fixation devices. The bore 2820 of each cannulae 2816 can have a unique internal diameter that is adapted to receive a particular instrument or fixation device. The internal diameter may also be selected to prevent the use of the incorrect instrument or device with the guide 2810. The bore diameter and/or the length of the cannulae 2816 may also prevent the instrument or device from advancing into the cannulae 2816 beyond a predetermined distance, thereby providing a hard stop for depth control. The bore 2820 may also have a shape adapted to align the tool or fixation device in a predetermined orientation of use. Additionally, a protrusion, key, notch, or void may be formed on the cannulae 2816 or in the bore 2820 to one or more of: prevent the use of the incorrect instrument or device; prevent an incorrect orientation of the correct tool or device; and prevent over insertion of the tool or device. For example, in one embodiment of the present invention, the cannulae bore 2820 may include an instrument contact surface that is associated with a feature of the tool, such as a protrusion, to control the depth or orientation of insertion of the tool. Thus, the cannulae 2816 may be adapted to prevent the instrument or fixation device from advancing too far into the boney anatomy of the patient or otherwise being misused. The guide 2810 may include features adapted to be grasped or manipulated by a surgeon. Accordingly, gripping features 2829 may be formed on a portion of the guide 2810. In one embodiment, the gripping features 2829 comprise protrusions. The protrusions 2829 may be of any shape or size selected to facilitate grasping of the guide 2810 in a surgical environment. In one embodiment, the protrusions 2829 are formed on a portion of the medial body 2812. The protrusions 2829 may comprise ridges or bumps. In one embodiment, the protrusions 2829 comprise three generally parallel ridges formed on opposing sides of each portion 2812A, 2812B of the medial body 2812. However, it will be appreciated than any number of protrusions may be formed with the griping feature 2829. Optionally, the gripping features 2829 of the medial body portion 2812A may be different than the gripping features of medial body portion 2812B. In this manner, a surgeon or other user can determine an orientation of the guide 2810 by feel without being required to look at the guide. In one embodiment, the gripping features 2829 are formed on a portion of the guide 2810 that extends beyond the patient's anatomy when the guide 2810 is in a predetermined position in contact with the patient's anatomy. Although not illustrated in Fig. 32 the guide 2810 may further comprise attachment points formed in one or more of the medial body 2812, the cannulae 2816, and the legs 2824. The attachment points are adapted to receive one or more secondary 2840 or tertiary cannulae 2850. The cannulae 2840/2850 may include a bore 2820A or a cutting slot to guide an instrument to target another portion of the patient's anatomy. In one embodiment, the cannulae 2840, 2850 are adapted to target one or more predetermined portions of the cervical spine (i.e., Cl-Sl and ilium). In one embodiment, the attachment points comprise slots to receive extensions 2842 of the cannulae 2840, 2850. In one embodiment, the slots may also direct the path of a blade or other cutting instrument, or to receive a measurement aid or tool for facilitating the surgeon/user in identifying landmarks, surrounding boney anatomy, placement of implanted devices, or for surgical planning. The guide 2810 may further comprise slots formed in the medial body 2812 or the cannulae 2816. The slots may be the same as or similar to slots 1830. In one embodiment, the slots are adapted to direct the path of a blade or other cutting instrument in a manner similar to cutting slots 20-820 of all embodiments described herein. Alternatively, the slots of guide 2810 may be adapted to receive the secondary 2840 or tertiary cannulae 2850 as further described in conjunction with Fig. 31. In another embodiment, the guide 2810 is adapted to receive a cutting guide 10 in a manner similar to guide 1810A illustrated in Fig. 25D. The cutting guide 10 may be received by a slot formed in one or more of the medial body, cannulae, and legs. Optionally, the cutting guide 10 may be integrally formed with the guide 2810. Referring now to Figs. 33A-33B, another embodiment of a patient-specific guide 2910 of the present invention is illustrated. The guide 2910 is similar to guide 2810 and generally includes a medial body 2912 and a cannulae 2916. The cannulae 2916 are the same as, or similar to, the cannulae 2816 and may include an extension 2919 and a bore 2920. The extensions 2919 are generally expanded radially compared to the extension 2819 of guide 2810. Accordingly, the extensions 2919 cup around the patient's anatomy and the contact surfaces 2918 have a larger surface area than contact surfaces 2818. More specifically, the increased radial size of the extensions 2919 enable the contact surfaces 2918 to contact more variable bone surfaces of the patient. In one embodiment, the extensions 2919 are adapted to contact at least a portion of one or more of the patients' superior articular process and the pars. The extensions 2919A, 2919B can have similar or different shapes as needed based on the patient's anatomy. For example, extension 2919A wraps around a portion of the circumference of cannulae 2916A and extension 2919B wraps around the entire circumference of cannulae 2916B. Additionally, the radius of the extensions 2919 may be varied. In one embodiment, the radius of extension 2919A is different than extension 2919B. The guide 2910 also includes a gripping feature 2929 of another embodiment of the present invention. The gripping feature 2929 comprises a depression 2930 formed in a portion of the medial body 2912. One or more protrusions 2932 may be associated with, or arranged around, the depression 2930.

The guide 2910 may also include indicia 2928 to identify a sequence of use or portions of the patient's anatomy with which the guide 2910 is to be used. Referring now to Figs. 34A, 34B, another embodiment of a patient specific guide 3010 of an embodiment of the present invention is illustrated. The guide 3010 is similar to guides 2810 and 2910 and generally includes a medial body 3012, legs 3024, cannulae 3016, and gripping features 3029 comprising a depression 3030 and protrusions 3032. Patient specific contact surfaces 3018, 3025, 3026 may be formed on one or more of the cannulae 3016, legs 3024, and medial body 3026 the same as (or similar to) those on the guides 2810, 2910. Each of the cannulae 3016 may include an extension 3019 and a bore 3020. The bore 3020 is the same as any of the bores 1820, 1920, 2820, 2920 described herein. The extensions 3019 are similar to the extensions 2919 and have an expanded radius compared to the extensions 2819. However, the extensions 3019 have a different alignment and shape compared to the extensions 2919. More specifically, as best seen in Fig. 34B, the extensions 3019 have contact surfaces 3018 that vary in length axially around the circumference of the cannulae 3016. Additionally, the extensions 3019, cannulae 3016, and the contact surfaces 3018 define a chamber or concavity 3034 proximate to the bore 3020. A concavity 3036 similar to concavity 3034 may also be formed in the distal end of each leg 3024. The concavities 3034, 3036 provide a focused contact between the patient specific contact surfaces 3018, 3025 of the cannulae 3016 and legs 3024 and the patient's anatomy. More specifically, without the concavities 3034, 3036, the smooth surfaces of the cannulae 3016 and/or legs 3024 may contact soft tissue of the patient that has not been cleaned from the bone. This contact may prevent proper alignment of the guide 3010. Said another way, the concavities 3034, 3036 prevent the cannulae 3016 and legs 3024 from contacting soft tissue that may not have been cleaned off of the bone. Accordingly, the concavities 3034, 3036 help ensure proper alignment of the guide 3010 with the targeted portion of the patient's anatomy. The concavity 3034 of the cannulae 3016 may also receive and collect bone material created by a boring instrument, such as a drill bit, guided by the bore 3020. In this manner, bone material may exit a hole formed in bone of the patient and be received within the concavity 3034. The bone material created during the medical procedure is thus collected and does not push the guide 3010 away from the target portion of the patient's anatomy, ensuring that the guide 3010 remains in a predetermined orientation.

Referring now to Figs. 35A - 35C, still another embodiment of a patient specific guide 3110 of the present invention is illustrated. The guide 3110 is similar to guides 2810, 2910, and 3010 and generally includes a medial body 3112, cannulae 3116, and legs 3124. The cannulae 3116 may include a bore 3120 that is the same as bores 1820, 2820, 2920, or 3020. Extensions 3119 with an increased radius may be formed on each cannulae 3116 similar to the extensions 2919, 3019 of guides 2910, 3010. Patient specific contact surfaces 3118, 3125 may be formed on one or more of the cannulae 3116 and legs 3124 as described herein in conjunction with guide 2810. The guide 3110 also includes at least one cutaway or aperture 3138, illustrated in Figs. 43A, 43B, through the cannulae 3116. The aperture 3138 intersects at least a portion of the bore 3120 and enables bone material to exit the cannula during drilling of the patient's bone. As a consequence, the bone material does not collect between the guide 3110 and the patient's anatomy, such as a vertebrae 4, which may potentially interfere with the alignment of the guide 3110. Although only one aperture 3138 is illustrated on cannula 3116A, apertures 3138 may be formed on each cannulae 3116 of the guide 3110. Additionally, the apertures 3138 can be formed in different portions of the cannulae 3116 than illustrated in Fig. 35. The apertures 3138 may also be formed to have a shape adapted to avoid anatomy of the patient, such as an adjacent vertebra. For example, the aperture may have one or more of a different length, width, and shape than illustrated in Fig. 35. In this manner, the apertures 3138 ensure the guide 3110 is in a predetermined alignment with a target portion of the patient's anatomy. Referring now to Figs. 36A-36F, still more patient specific guides 3210 of an embodiment of the present invention is illustrated. The guides 3210 generally includes a medial body 3212, cannulae 3216, legs 3224, and secondary legs 3242. The secondary legs 3242 have contact surfaces 3225A adapted to contact predetermined portions of the patient's anatomy. The contact surfaces 3225A are formed in the same manner as contact surfaces 2818, 2825 of guide 2810. In one embodiment, the contact surfaces 3225A are formed using the method of Fig. 2. The contact surfaces 3225, 3225A of the legs 3224, 3242 are aligned to contact one or more of the lamina, pars, articular processes, and spinous process of the patient's anatomy 4. Additionally, the contact surfaces 3325, 3225A may be patient specific as described herein. The contact surfaces 3225, 3225A of the legs may also include concavities the same as or similar to the concavity 3036 of guide 3010.

In one embodiment, one or more of the cannulae 3216 have a length selected such that distal ends of the cannulae 3216 do not contact the patient's anatomy. Accordingly, as illustrated in Figs. 36B, 36C, the distal ends of the cannula 3216 are separated by a predetermined distance from a vertebrae 4 of the patient when the guide is aligned with the vertebrae 4. Alternatively, one or more of the cannulae 3216 may have an increased length such that the distal end of the cannulae 3216 contacts a predetermined portion of the patient's anatomy. Thus, the distal end of the cannulae 3216 may include one or more of patient specific contact surfaces, an extension, a concavity, and an aperture the same as, or similar to, contact surfaces 2818, 2918, 3018, 3118, extensions 2819, 2919, 3019, 3119, concavities 3034, and aperture 3138. Referring now to Figs. 36D-36F, perspective views of another patient-specific guide 3210A adapted to be positioned within an incision against a patient's boney anatomy are provided. In one embodiment, the guide 3210A is adapted for use in a surgical procedure involved a vertebrae 4 of a patient to guide instruments and fixation devices along one or more trajectories A, B. However, the guide 3210A may be used to guide instruments and for placement of fixation devices in surgical procedures involving other boney anatomy of the patient. The guide 3210A is similar to the guide 3210 described in Figs. 36A-36C. Accordingly, the guide 3210A generally includes one or more of a medial body 3212, legs 3224, and secondary legs 3242 that are the same as, or similar to, the medial body, legs, and secondary legs of guide 3210. Optionally, the guide 3210 may include one or more cannulae 3216. The optional cannulae 3216 may further include a bore 3220 for placement of a temporary fixation pin to temporarily fix the guide 3210A to the patient's anatomy 4 during a surgical procedure. Guide 3210A also includes at least one external cannula 3250 (or "posterior cannula") associated with at least one internal cannula 3260 (or "anterior cannula"). Pairs of associated external and internal cannula 3250, 3260 are substantially collinearly aligned. After the guide 3210A is positioned against the patient's anatomy 4 through a first incision, the internal cannula 3260 is targeted by the surgeon through a second incision in the patient's soft tissue. The internal cannula 3260 improves the mechanical guidance of instruments into the patient's anatomy 4. In one embodiment, the external cannula 3250 are interconnected to a support element 3254. The support element 3254 may be of any size. Optionally, the support element 3254 is sized to position the external cannula 3250 laterally beyond the width of the guide 3210A. The external cannula 3250 may optionally be releasably interconnectable to the medial body 3212. For example, as illustrated in Fig. 36E, the external cannula 3250 may include a projection 3256 adapted to be received within a corresponding slot 3213 formed in the guide 3210A. In one embodiment, the slot 3213 is formed in the medial body 3212 and is the same as (or similar to) one of the slots 1830 of guide 1810. The internal cannula 3260 are interconnected to a portion of the guide 3210A to be positioned within an incision through the patient's skin S. In one embodiment the internal cannula 3260 are interconnected to a distal portion of the cannula 3216. However, the internal cannula 3260 may optionally be interconnected to other portions of the guide 3210A including the legs 3224 and/or the secondary legs 3242. The external cannula 3250 include bores 3252 that are generally concentrically aligned with bores 3262 of the corresponding internal cannula 3260. Accordingly, in combination, corresponding pairs of external and internal cannula 3250, 3260 define a virtual cannula of an extended length. However, by using a pair of corresponding external and internal cannula 3250, 3260, the size of an incision required to position the guide 3210A may be decreased compared to an incision required for a guide with a cannula of a length extending from the external cannula 3250 to the internal cannula 3260. Further, by positioning the internal cannula 3260 on a distal portion of the guide 3210A proximate to the patient's anatomy, the center of gravity of the guide 3210A is moved closer to the patient's anatomy 4. Thus, the guide 3210A is docked low and stably on the patient's bone 4, improving the accuracy of k-wires and other instruments guided along trajectories A, B. The internal cannula 3260 further include an aperture 3264. The aperture 3264 forms a channel from the bore 3262 to an exterior of the internal cannula 3260. The aperture 3264 is sized to allow a k-wire to pass through the aperture 3264 such that the guide 3210A may be removed from the patient after a k-wire oriented by the guide 3210A is positioned within the patient's anatomy. In one embodiment, the aperture 3264 comprises a slot that extends longitudinally from an exterior surface of the cannula 3260 to the bore 3262. As illustrated in one embodiment in Fig. 36F, when an instrument, such as a sleeve 1854 is received at least partially in the bore 3262, the aperture 3264 is obstructed such that a k-wire or other instrument positioned within a bore 1856 of the sleeve 1854 is retained within the bore 3262 of the internal cannula 3260B.

Referring now to Figs. 37A-37D, another patient specific guide 3310 of the present invention is illustrated. In one embodiment, the guide 3310 is adapted to be positioned proximate to a patient's ilium 8, as indicated by indicia 3328 that indicate a direction toward the sacral vertebrae Si and S2. The guide 3310 is similar to guide 3210 and generally comprises a medial body 3312, cannulae 3316 including bores 3320, legs 3324, and secondary legs 3342. The legs 3324, 3342 may each include patient specific contact surfaces the same as, or similar to, the contact surfaces 3225, 3225A. In one embodiment, distal ends of the cannulae 3316 do not contact the patient's anatomy. Alternatively, one or more of the cannulae 3316 may include patient specific contact surfaces similar to the contact surfaces 2818 of guide 2810. The guide also includes secondary cannulae 3340. Each secondary cannulae 3340A, 3340B may have a unique trajectory to target portions of the patient's anatomy. The secondary cannulae 3340 are similar to cannulae 3316 and have a predetermined length and orientation with respect to the guide 3310. The cannulae 3340 include bores 3320A that are formed in a manner similar to bores 1820, 2820, 3320. Accordingly, the bore 3320A of each secondary cannulae 3340 may be used to guide instruments to another targeted portion of the patient's anatomy. In one embodiment, the secondary cannulae 3340 are oriented to guide an instrument in an S2-alar or an S2-alar-iliac trajectory. In one embodiment, the bores 3320A of the secondary cannulae 3340 are oriented to guide a drill bit to form a pilot hole in the S2-alar or an S2-alar-iliac trajectory. The secondary cannulae 3340 are spaced from the guide 3310 by support elements 3341 of a predetermined length. In one embodiment the support elements 3341 are interconnected to the cannulae 3316. However, the support elements 3341 may be interconnected to other portions of the guide 3310, such as the medial body 3312 and/or the legs 3324. Optionally, the secondary cannulae 3340 may be releasably interconnected totheguide3310. Accordingly, the secondary cannulae 3340 can be added to, or removed from, the guide 3310 during a surgical procedure. Further, the secondary cannulae 3340A, 3340B may be used to perform a first procedure on the patient's anatomy and then replaced by subsequent secondary cannulae 3340 that are used to perform additional procedures. In another embodiment, the secondary cannulae 3340 may be integrally formed with the guide 3310.

Referring now to Figs. 38-45, a patient-matched interbody guide 3410 is described. The guide 3410 is adapted for the placement of one or more interbody devices, such as an implantable cage for introducing one or more bioactive substances or bone graft material, or an artificial disc. Optionally, the guide 3410 may be used to arrange one or more tools used in the procedure. The guide 3410 is adapted to be inserted between two adjacent vertebral bodies and to distract two or more anatomical features. For example, an anterior, posterior, posterior lateral, or direct lateral approach to the disc space may be achieved with the guide 3410 to facilitate placement of implants in oblique, direct lateral, or posterior approaches. In one embodiment, the interbody guide 3410 is designed following acquisition of a scan of the patient's anatomy with a medical imaging device. The scan is segmented into 3D models of each vertebra. These 3D models are then modified in CAD to simulate the correction desired by the surgeon. Once the desired correction is appropriately simulated, a guide 3410 is generated that will allow the surgeon to make the planned corrections intraoperatively. The guides may then be manufactured through 3D printing, rapid prototyping, or an alternative method as described herein. The guide 3410 may take on other shapes, orientations, thicknesses, etc. without deviating from the novel aspects of this disclosure. Similarly, guide 3410 may be of any size and may comprise extensions or handles to aid in grasping or manipulating the guide 3410 as desired. Referring now to Fig. 38, the patient-matched guide 3410 is shown in an exploded view to demonstrate how a plurality of components may be fabricated using the system and method described above for a particular surgical procedure. The components of the guide 3410 generally include a patient-specific insert 3412, a guide sleeve 3414, and connectors 3416, which, in a finally assembled state, form the patient-matched guide 3410 shown in Figure 50. Referring now to Figs. 38-39, the insert 3412 generally comprises a proximal surface 3418, a distal surface 3420, two projections 3422, 3424 extending from the distal surface, an aperture 3426, and bores 3428. The projections 3422, 3424 are adapted to fit directly to aspects of a patient's anatomy. More specifically, the projections 3422, 3424 are adapted to be positioned between a superior vertebrae and an inferior vertebrae within the intervertebral disc space. The shape of the projections 3422, 3424 is predetermined to match at least a portion of a curvature of the adjacent vertebrae and to facilitate the insertion of an implant with a predetermined size and shape into the intervertebral space.

The projections include a variety of patient-contacting surfaces which permit the insert 3412 to mate with portions of one or more vertebral bodies. For example, the upper surfaces 3430, 3432, lower surfaces 3434, 3436, and interior surfaces 3438, 3440 of the respective projections 3422, 3424 may include patient specific contact surfaces. The distal surfaces 3420 of the insert 3412 may also include patient specific contact surfaces. The patient specific surfaces are adapted to one or more of: align the insert 3412 in a predetermined position with respect to the patient's anatomy; hook around a portion of the patient's anatomy; prevent unintended or inadvertent movement of the insert 3412 during a surgical procedure; and displace soft tissue. In one embodiment, the patient specific surfaces comprise relatively thin extensions to displace soft tissue. In one embodiment, the insert 3412, or portions thereof, may be manufactured from a material that is at least partially flexible or deformable. In another embodiment, the insert 3412 is manufactured from a material with shape memory, such as Nitinol. Additionally, or alternatively, the projections 3422, 3424 may be asymmetrical. Thus, in one embodiment, one projection has a shape and/or size that is different than the other projection. Additionally, the angle and orientation of each projection with respect to the distal surface 3420 of the insert 3412 can be varied to match the anatomy of the patient, or to avoid a portion of the patient's anatomy. In one embodiment, the shape of the projections 3422, 3424 does not provide correction of deformities of the patient's anatomy. In another embodiment, the shape of the projections provides at least some correction of the patient's deformity. Portions of the projections may have a tapered shape that can be used to distract the vertebrae. For example, the distal portion 3442, 3444 of each projection 3422, 3424 may comprise a full-radius or bullet-shaped nose for ease of insertion. Additionally, or alternatively, the distal portions may have a wedge shape. The upper surfaces 3430, 3432 of the projections 3422, 3424 may not be parallel to the lower surfaces 3434, 3436. Further, the upper and lower surfaces may have different shapes. For example, and referring now to Fig. 39, the projections may taper as they extend distally away from the distal surface 3420 of the insert 3412. Optionally, a distal portion of the projection 3422 may have a first thickness 3446 substantially equal to, or slightly greater than, a thickness of an implant. A proximal portion of the projection 3422 may have a second thickness 3448 that is greater than the first thickness 3446 and greater than the thickness of the implant. In this manner, a surgeon may "over distract" the adjacent vertebrae. The over distraction facilitates easier and safer access to the intervertebral space, placement of the implant, and generates lordosis or other planned correction of the patient's anatomy. The projections 3422, 3424 may also be adapted to prevent a user from advancing the insert 3412 into the intervertebral space beyond a predetermined distance. For example, a protrusion or notch may be formed on a portion of at least one of the projections 3422, 3424 to provide a hard stop. Alternatively, a protrusion or notch may be formed on the projections or some other portion of the insert 3412, such as the distal surface 3420, to prevent an incorrect orientation of the guide 3410. The stops, protrusions, or notches may be specific to the patient's anatomy and allow for protection of neural elements or other features of the patient's anatomy. The guide 3410 and the insert 3412 may further comprise one or more indicia for identifying the guide for a particular patient, a level of the patient's spine, or other indicia indicating the direction, orientation, use, or purpose of the guide. Additionally, or alternatively, the projections 3422, 3424 and other portions of the interbody guide 3410 may include means to indicate a relative position of the projections 3422, 3424 into the intervertebral space as the insert 3412 is advanced or withdrawn. The means to indicate may be the same or different for each of the projections. A manual or mechanical impact force may be applied to the insert 3412 to advance the projections 3422, 3424 between the adjacent vertebrae. Accordingly, in one embodiment of the present invention, the insert 3412 is made of a sufficiently rigid and durable material to receive an impact force from a hammer or other impact device. Although illustrated with a generally oval shape, one of skill in the art will appreciate that the aperture 3426 may have any desired shape, including an asymmetrical shape. For example, the aperture 3426 may be shaped to receive a curved or asymmetric implant. Optionally, slots or protrusions may be formed on a sidewall 3450 of the aperture to ensure the implant is inserted in a predetermined orientation. Additionally, the size or shape of the aperture 3426 may be designed to achieve greater visibility to the surgeon/user, or to facilitate placement of one or more instruments or other devices into the intervertebral space. Notches 3452 may be formed in the aperture 3426 that align with keys 3454 of the guide sleeve 3414. The interaction of the notches 3452 and keys 3454 may ensure the guide sleeve 3414 is properly aligned with the aperture 3426. The guide sleeve may include an aperture 3456 to guide instruments and/or implants inserted into the intervertebral space to a planned depth and orientation. It will be appreciated that the guide sleeve aperture 3456 may have a different size and shape than the insert aperture 3426. Additionally, or alternatively, the aperture 3456 may also include slots or protrusions to ensure implants or instruments are inserted in the predetermined orientation. The guide sleeve 3414 may have any size and shape selected to be at least partially received in the insert aperture 3426. Further, the guide sleeve 3414 may project at least partially from the proximal surface 3418 of the insert 3412. Optionally, a proximal portion of the guide sleeve 3414 may project at least partially beyond an incision and the patient's skin during the surgical procedure. The guide sleeve 3414 may be formed of any material. Optionally, the material of the guide sleeve may the same as, or different from, the material of the insert 3412. In one embodiment, the guide sleeve is formed of a material that is of sufficient strength that breaking and/or flaking of the sleeve material is avoided. Accordingly, the guide sleeve may withstand the effects of high-speed cutting tools without damage and without permitting material from the guide sleeve to become deposited in the intervertebral space. Any number of different guide sleeves 3414 ... 3414N may be releasably received in the insert aperture 3426 for use with the interbody guide 3410. Each guide sleeve 3414 may be adapted to guide a different insert or tool during a surgical procedure. For example, a first guide sleeve may be introduced into the insert aperture 3426 to guide a first tool or insert. The first guide sleeve may then be replaced by a second guide sleeve introduced into the insert aperture. The second guide sleeve may guide a second tool or insert. The second tool or insert may have a different size, shape, or purpose than the first tool or insert. Referring now to Fig. 40, an embodiment of a guide sleeve 3414A with a guide slot 3458 is illustrated in a position of use in the insert aperture 26. The guide slot 3458 has a size and orientation selected to direct the path of an implant, a blade, cutting tool, or other instrument. In one embodiment, the guide slot 3458 is the same as, or similar to, and includes features of any of the slots 20, 120, 320, 420, 520, 720, 820 described herein. Some implants, such as motion preserving and disc replacement implants, include fins or other surfaces that extend into the end plates of adjacent levels of the patient's spine. For proper placement of these implants the surgeon must remove portions of the bone from each adjacent level of the spine. Accordingly, the slot 3458 can have any shape determined to guide cuts for a planned removal of a portion of each of the adjacent vertebrae of the particular patient. For example, the slot may have a shape to guide instruments to provide straight, concave, convex, or other shaped cuts.

The slot 3458 may be sized or shaped to receive a particular cutting tool, prevent inappropriate use of the particular cutting tool, and prevent the use of an inappropriate tool. Additionally, the slot may be shaped to guide a cut around a neural element of the patient or to prevent a cut into a neural element. Accordingly, the slot 3458 can be used to guide instruments along a presurgically planned pathway while controlling instrument orientation and depth. Further, the width of the slot may change to control the size of a cutting tool that fits through the slot, or fit into different portions of the slot. By using the slot 3458 of guide sleeve 3414A inserted into the insert aperture 3426, a surgeon may confirm positioning and alignment of the cutting trajectory and path prior to initiating the procedure. Stops may be formed in the slot 3458 to limit or control the depth of insertion of the cutting tool. The stops may be specific to the patient's anatomy and allow for protection of neural elements of the patient or to prevent unintended removal of portions of the vertebrae. The slot 3458 may also be keyed to ensure depth control while cutting. For example, the slot may include a key that alters the depth of cutting by the tool as the tool is guided through the slot. The key may correspond to a feature, such as a protrusion, on the tool that limits the depth of insertion of the tool. The slot 3458 of guide sleeve 3414A may be adapted to receive different types and sizes of tools or implants. Additionally, or alternatively, the guide sleeve 3414A may be operable to receive only one particular tool or implant. Additionally, or alternatively, and referring now to Fig. 41, a guide sleeve 3414B of another embodiment may include a guide surface 3460 formed on a sidewall of the aperture 3456B. The guide surface 3460 has a predetermined angle to guide instruments or implants during the surgical procedure. For example, the surface 3460 may guide an instrument for disc space preparation. Additionally, the surface 3460 may be shaped to guide an implant, such as, but not limited to, a motion sparing implant, an interbody fusion device, a plate, for oblique insertion angles. The guide sleeve 3414B may also include a guide surface with a defined track according to a planned oblique access angle to facilitate insertion and alignment of an implant. It will be appreciated that the guide surface 3460 may be formed on any portion of the aperture 3456B of the guide sleeve 3414B. Different guide sleeves 3414, 3414A, 3414B ... 3414N can be provided with features to ensure operations are performed in a preplanned sequence. In one embodiment, guide sleeves 3414, 3414A ... 3414N are formed to interconnect together in a planned sequence. Accordingly, a first procedure may be performed with sleeve 3414 and insert 3412. Sleeve 3414A may then be interconnected to sleeve 3414 and insert 3412 for use during a second procedure. Sleeve 3414B may then be interconnected to sleeve 3414A, 3414 and insert 3412 for use during a third procedure. In this manner, sleeves 3414 may be used sequentially without removing previous sleeves from the insert 3412. This may be beneficial, for example, when a sleeve 3414 is holding an instrument, such as a pin. The instrument will not require adjustment when a subsequent sleeve 3414A is added to theinsert3412. The bores 3428 of the insert 3412 may also be patient specific. Accordingly, the size, location, and trajectory of the bores 3428 may be determined based on the patient's anatomy. Further, the trajectory of each bore may be selected to target, or avoid, a specific portion of the patient's anatomy. Accordingly, each of the bores may have a different shape, width, depth, and orientation adapted to guide a specific instrument or fixture in a specific orientation. Although three bores are illustrated, it will be appreciated that any number of bores may be formed in the insert, including no bores. The bores can receive a connector or fixture 3416, such as a pedicle screw, to temporarily fix the guide 3410 to the patient's spine. Placing a fixture through the bores 3428 can increase stability of the guide 3410 during use. Optionally, the bores 3428 may be adapted to receive a tool, such as a tool for forming a bore in the patient's anatomy. Accordingly, each bore 28 may have a length, shape, protrusion, and/or a diameter selected to prevent the use of the improper tool or device, prevent improper use of a predetermined tool or device, and ensure proper use of the predetermined tool or device. Additionally, the bores 3428 may be used to deliver graft material into the intervertebral space. For example, in one embodiment, the bores are operable to conduct bone graft material and other substances from a surgical tool, such as a syringe, to a predetermined portion of the intervertebral space. Referring now to Figs. 42-43, the patient-matched guide 3410 is shown in one potential location of use relative to a unique anatomical grouping for assisting the surgeon for placing one or more interbody devices. More specifically, Fig. 42 illustrates the guide 3410 between superior VS and inferior VI adjacent vertebrae. The inferior vertebrae is not illustrated in Fig. 43 for clarity. Figs. 44A, 44B illustrate the guide 3410 of Fig. 42 with a different guide sleeve 3414A including guide slot 3458 inserted in the aperture of the insert 3412.

Guides 3410 of the present disclosure may be adapted for use between any two adjacent vertebrae. For example, and referring now to Fig. 45, a guide 3410A of another embodiment is illustrated between two different vertebrae VS, VI. The guide includes insert 3412A that includes a first projection 3422A and a second projection (not illustrated) similar to projection 3424 that include patient specific contact surfaces adapted to contact the two vertebrae VS, VI illustrated in Fig. 45. However, the first and second projections of insert 3412A have a different size or shape compared to the projections of insert 3412. Additionally, or alternatively, the insert aperture 3426A of guide 3410A may have a size or shape that is different than the size and shape of the aperture 3426 of guide 3410. In this manner, guide sleeves 3414A ... 3414N adapted for use in a procedure with guide 3410 may not fit, and thus cannot be misused, with guide 3410A. Optionally, the insert aperture 3426A may have the same size and shape as aperture 3426. It is expressly understood that other shapes for the interbody guide 3410 and its components are equally practical and considered within the scope of the disclosure. Additionally, or alternatively, at least a portion of the proximal end of the guide may be configured to extend outside of the patient during a surgical procedure. The foregoing discussion of the disclosure has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein.

Claims

CLAIMS 1. A patient-specific cutting guide, comprising: a body having a proximal portion and a distal portion; a first slot portion having a first width, the first slot portion extending from the proximal portion to the distal portion of the body of the guide; a second slot portion having a second width, the second slot portion extending from the proximal portion to the distal portion of the body of the guide, the second width different from the first width; the distal portion of the body comprising at least a first patient specific contour on one side of the first slot portion and a second patient-specific contour on the opposite side of the first slot portion for mating with a patient's boney anatomy; the distal portion of the body further comprising at least a third patient specific contour on at least one side of the second slot portion for mating with a patient's boney anatomy; wherein at least one of the first slot portion and the second slot portion is oriented in a path determined from the anatomical data of the patient; and wherein the at least a first, second and third patient-specific contours are determined from the anatomical data of the patient and are shaped to substantially conform to a specific portion of the patient's boney anatomy.
2. The patient-specific cutting guide of claim 1, wherein the first and second slot portions each have a predetermined trajectory determined from the anatomical features of a patient and configured to permit an instrument to pass through the body of the guide and make multiple incisions along a patient's boney anatomy.
3. The patient-specific cutting guide of claim 1, wherein the path of the first and second slot portions comprises depth control, angle, and orientation for facilitating insertion and movement of an instrument along the path.
4. The patient-specific cutting guide of claim 1, further comprising a first insert configured to be received in the first slot portion of the body of the guide and a second insert configured to be received in the second slot portion of the body of the guide.
5. The patient-specific cutting guide of claim 4, wherein the first insert defines a first path for guiding an instrument or tool and the second insert defines a second path for guiding an instrument or tool, each of the first and second paths comprising unique depth control, angle, and orientation for facilitating movement of the instrument along the respective first and second paths.
6. The patient-specific cutting guide of claim 5, wherein the first and second paths of the first and second inserts each has a predetermined trajectory determined from the anatomical features of a patient and the predetermined trajectory of the first path is different from the predetermined trajectory of the second path.
7. The patient-specific cutting guide of claim 6, wherein the first and second paths are independently configured to permit the instrument or tool to pass through the body of the guide and make multiple incisions along different depths and trajectories.
8. The patient-specific cutting guide of claim 5, wherein either of the first and second paths of the first and second inserts is configured to guide the instrument or tool for removal of a specific portion of the patient's boney anatomy.
9. The patient-specific cutting guide of claim 1, wherein the first, second and third patient-specific contours are configured to contact one or more of a lamina, a pars interarticularis, a portion of a transverse process, a superior articular process, and an inferior articular process.
10. The patient-specific cutting guide of claim 1, wherein the first, second and third patient-specific contours are configured to contact a portion of a patient's boney anatomy that has previously been modified by a surgeon.
11. The patient-specific cutting guide of claim 1, wherein the first and second slot portions are each adapted to receive and guide an instrument for achieving a pedicle subtraction, an osteotomy, a laminectomy, a facetectomy, a Smith-Peterson osteotomy and a vertebral column resection.
12. The patient-specific cutting guide of claim 1, further comprising a frame configured to be placed at least partially on the boney anatomy of the patient, and wherein the body of the guide may be selectively interconnected to the frame.
13. The patient-specific cutting guide of claim 1, wherein the body is comprised of at least a first and a second section that are selectively interconnected to each other to form the guide.
14. The patient-specific cutting guide of claim 1, wherein the guide is used to perform a first set of incisions along the patient's boney anatomy, and further comprising a second patient-specific cutting guide used to perform a second set of incisions along the patient's boney anatomy.
15. The patient-specific cutting guide of claim 14, wherein the second patient specific cutting guide comprises at least one patient-specific contour determined from the anatomical data of the patient and shaped to substantially conform to a specific portion of the patient's boney anatomy.