JP6654601B2 - Bone opener - Google Patents

Description

  The present invention relates to a bone opening device (opener).

  2. Description of the Related Art High tibial osteotomy (HTO), which changes the shape of a leg from a so-called “O leg” to an “X leg”, has conventionally been performed. In this high tibial osteotomy, the tibia is incised from the inside to the outside of the crotch, the incision is enlarged, and an artificial bone as a spacer is inserted into the enlargement to correct the angle of the tibia. There is an open wedge method. In the open wedge method, a first blade having a pair of long first swinging members whose tips are rotatably supported, and the first blade is detachably connected to the first blade, and the tips are separated from each other. An expander including a second blade having a pair of long second swing members rotatably supported can be used (for example, see Patent Document 1).

  When inserting an artificial bone into the enlarged portion of the tibia using the dilator disclosed in Patent Document 1, first, the first blade and the second blade were assembled before the artificial bone was inserted. In the assembled state, they are collectively inserted into the incision, and the rotation angle of each rocking member is adjusted in the inserted state. Thereby, the incision is further expanded. Next, the first blade and the second blade are separated, and one of these blades is removed. As a result, a space is formed in the enlarged portion to the extent that the one blade is removed. Thereafter, the artificial bone can be inserted (supplemented) into this space.

  In the dilator described in Patent Document 1, the first blade and the second blade are configured such that a protrusion (engaging portion) formed on one of the blades is engaged with a concave portion of the other blade. , The assembled state is maintained. However, when the first blade and the second blade are separated from such an assembled state and one of the blades is removed, first, the blades are inserted in a direction intersecting the insertion into the enlarged portion. Until the projections and the recesses are disengaged from each other, the removal operation cannot be performed. Therefore, the extraction operation cannot be performed quickly, and as a result, there is a problem that it takes time to place the artificial bone. In addition, the first blade and the second blade have a correction angle (opening angle) of 10 ° because a protrusion (engaging portion) protrudingly formed on one blade is engaged with a concave portion of the other blade. If it is smaller than about 6 to 8 degrees, the engagement between the projection and the recess is not completely released after closing one of the blades, and the projection and the recess interfere with each other and the first blade is closed. There is a problem that it becomes difficult to separate the second blade from the second blade.

  Further, when adjusting the rotation angle of each rocking member, the expander described in Patent Document 1 applies an operating force to one rocking member to adjust the rotation angle of the rocking member. By adjusting the rotation angle, the rotation angle of the other swinging member is also adjusted in conjunction therewith. However, at the time of adjusting the rotation angle of each rocking member, the blades are in an easily disassembled state because the blades are maintained in an assembled state only by the engagement of the projections and the recesses. If the blades are unintentionally disassembled, the operating force from one of the swing members is not sufficiently transmitted to the other swing member. In this case, there is a problem that it is difficult to stably adjust the rotation angle of one swing member and the rotation angle of the other swing member to the same angle.

Japanese Patent No. 4736091

  An object of the present invention is to reliably and stably perform the operation of adjusting the rotation angle of the first blade and the operation of adjusting the rotation angle of the second blade when the artificial bone is placed in, for example, an enlarged portion. Another object of the present invention is to provide a bone opening device that can perform the separation operation of the first blade and the second blade after the operation at an accurate timing and quickly.

Such an object is achieved by the following (1) to (9) of the present invention.
(1) a first blade having a pair of first elongated bodies whose tips are rotatably connected to each other;
A second blade having a pair of second elongated bodies which are provided side by side with the first blade and whose tip portions are rotatably connected to each other;
The first elongated body and the second elongated body are detachably attached to the first elongated body and the second elongated body, and in the attached state, the first blade and the second blade are connected side by side and connected. And an angle adjustment mechanism for adjusting a rotation angle between the first elongated members and a rotation angle between the second elongated members.

  Thus, when the artificial bone is to be placed, for example, in the enlarged portion of the tibia, the operation of adjusting the rotation angle of the first blade and the operation of adjusting the rotation angle of the second blade are reliably and stably performed. The separation operation of the first blade and the second blade after the operation can be performed at an accurate timing and quickly.

(2) The angle adjusting mechanism may be configured such that, in the mounted state, one of the pair of first elongated bodies and the one of the pair of second elongated bodies. A first engagement member that engages with one of the second elongate bodies located on the same side as the first elongate body;
In the mounted state, the other first elongated body of the pair of first elongated bodies is the same as the other first elongated body of the pair of second elongated bodies. A second engagement member engaged with the other second elongated body located on the side,
A screw member screwed to the first engagement member and the second engagement member,
The above (1), wherein the first engaging member and the second engaging member are configured to be able to approach or separate from each other in accordance with the rotation direction by rotating the screw member. Bone opening equipment.

  Thereby, the configuration (function) necessary for adjusting the rotation angle (the widening angle) can be integrated.

  (3) When the angle adjusting mechanism is attached to each of the first elongate bodies and each of the second elongate bodies, the base adjustment part of each of the first elongate bodies and each of the second elongate bodies are connected to each other. The bone opening device according to the above (1) or (2), which is inserted into a base end portion of a long body toward a distal end side to be in the mounted state.

  Thereby, when attaching and detaching the angle adjustment mechanism, the attachment and detachment can be performed easily and quickly by moving the angle adjustment mechanism back and forth along the longitudinal direction of the bone opening device or away therefrom. . Further, such an attaching / detaching operation can be performed even in a relatively small space.

  (4) The bone opening device according to any one of (1) to (3), further including a lock portion that maintains the mounted state.

  Thereby, for example, it is possible to reliably prevent the angle adjustment mechanism from being detached during use of the bone opening device, and thus it is possible to use the bone opening device with confidence.

(5) The bone opening device according to (4), wherein the lock portion has a ball plunger.
Thus, the lock portion can be made to have a simple configuration using the ball plunger, so that the operation of attaching and detaching the angle adjusting mechanism becomes easy.

  (6) One of the first blade and the second blade is independent of the other blade in a state where the maintenance of the attached state with respect to the other blade is released, and the one of the one blade is independent of the other blade. The bone opening device according to the above (4) or (5), wherein the rotation angle between the elongated bodies of the blade can be adjusted again by the angle adjusting mechanism.

  Thus, for example, during a procedure, one blade can be separated from the other blade and removed.

  (7) The one blade may be separated from the other blade along the longitudinal direction of the other blade after the rotation angle between the elongated members of the one blade is adjusted again. The bone opening device according to 6).

  Thus, for example, the removal of one blade can be performed smoothly without applying excessive force to the human body.

  (8) The bone opening according to (7), wherein the other blade has an angle maintaining member that maintains the rotational angle after the rotational angle between the elongated bodies of the other blade is adjusted. Appliances.

  Thus, when the artificial bone is placed, for example, in the enlarged portion of the tibia, the adjusted rotation angle can be reliably maintained, and thus the space for inserting the artificial bone can be ensured.

(9) The above-mentioned (1) to (8), further comprising a scale member provided on the first blade or the second blade and provided with a scale indicating a rotation angle between the elongated bodies of the blade. The bone opening device according to any one of the above.
Thereby, the rotation angle (opening angle) can be accurately grasped.

  According to the present invention, the connection state between the first blade and the second blade is reliably maintained by the angle adjusting mechanism. Then, when the artificial bone is placed, for example, in the enlarged portion, the rotation angle between the first elongated bodies and the rotation angle between the second elongated bodies is the minimum, that is, the first state in the closed state. As long as the blade and the second blade are inserted into the incision and the angle adjustment mechanism is operated as it is, the respective rotation angles can be surely increased collectively. Thereby, each of the rotation angles can be adjusted to the widening portion of the desired angle. As described above, according to the present invention, the operation of adjusting the rotation angles can be stably and reliably performed, and the operability is excellent.

  Further, after the adjustment of each of the rotation angles, by operating the angle adjusting mechanism, the connection state between the first blade and the second blade is released. Then, the separating operation of rapidly pulling out one of the first blade and the second blade along the longitudinal direction with respect to the other can be performed at an accurate timing and quickly.

FIG. 1 is a perspective view showing a use state of the bone opening device of the present invention. FIG. 2 is a perspective view showing a use state of the bone opening device of the present invention. FIG. 3 is a perspective view showing a use state of the bone opening device of the present invention. FIG. 4 is a perspective view showing a first blade provided in the bone opening device of the present invention. FIG. 5 is a perspective view showing a second blade provided in the bone opening device of the present invention. FIG. 6 is a perspective view showing an angle adjusting mechanism provided in the bone opening device of the present invention. FIG. 7 is a partial cross-sectional view of the mounting state of the angle adjustment mechanism viewed from the direction of arrow A in FIG. FIG. 8 is a sectional view taken along line BB in FIG. FIG. 9 is a perspective view showing a scale member provided in the bone opening device of the present invention. FIG. 10 is a perspective view showing an example of an artificial bone to be placed in an enlarged portion using the bone opening device of the present invention.

Hereinafter, a bone opening device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
1 to 3 are perspective views each showing a use state of the bone opening device of the present invention. FIG. 4 is a perspective view showing a first blade provided in the bone opening device of the present invention. FIG. 5 is a perspective view showing a second blade provided in the bone opening device of the present invention. FIG. 6 is a perspective view showing an angle adjusting mechanism provided in the bone opening device of the present invention. FIG. 7 is a partial cross-sectional view of the mounting state of the angle adjustment mechanism viewed from the direction of arrow A in FIG. FIG. 8 is a sectional view taken along line BB in FIG. FIG. 9 is a perspective view showing a scale member provided in the bone opening device of the present invention. FIG. 10 is a perspective view showing an example of an artificial bone to be placed in an enlarged portion using the bone opening device of the present invention. In the following, for convenience of description, the proximal side in FIGS. 1 to 6 and FIGS. 8 to 10 is referred to as “proximal (or rear)”, and the opposite side is referred to as “distal (or front)”. The upper side in FIGS. 1 to 10 is referred to as “upper (or upper)”, and the lower side is referred to as “lower (or lower)”.

  The bone opener (opener) 1 shown in FIGS. 1 to 3 includes a first blade 2A, a second blade 2B, an angle adjusting mechanism 5, and a scale member 6, and these are assembled in an assembled state. It has become. Then, the bone opening device 1 in this assembled state is used for an operation for correcting a tibia or the like. In the present embodiment, an open wedge method of high tibial osteotomy (HTO) will be described as an example of an operation in which the bone opening device 1 is used.

  Before describing the bone opening device 1, an artificial bone 90 to be placed in, for example, the medial condyle of the tibia using the bone opening device 1 in a high tibial osteotomy will be described.

  As shown in FIG. 10, the artificial bone 90 is formed of a wedge-shaped block. The wedge-shaped artificial bone 90 has an apex angle in a range of, for example, 7 ° or more and 15 ° or less, and is classified in increments of 1 ° within this range. Then, it is appropriately selected from the plurality of types of artificial bones 90 according to the case.

  Further, the artificial bone 90 is preferably made of a ceramic material as a constituent material. Since the ceramic material is excellent in workability, it is easy to adjust the shape, size, and the like by cutting using a lathe, a drill, or the like.

  Examples of the ceramic material include various ceramic materials, and bioceramics such as alumina, zirconia, and a calcium phosphate compound are particularly preferable. Among them, a calcium phosphate compound is particularly preferable as a constituent material of the artificial bone 90 because it has excellent biocompatibility.

  Examples of the calcium phosphate compound include apatites such as hydroxyapatite, fluorapatite, and carbonate apatite, dicalcium phosphate, tricalcium phosphate, tetracalcium phosphate, octacalcium phosphate, and the like. A mixture of more than one species can be used. Among these calcium phosphate compounds, those having a Ca / P ratio of 1.0 to 2.0 are preferably used.

  Among such calcium phosphate compounds, hydroxyapatite is more preferred. Hydroxyapatite has excellent biocompatibility because it has a structure similar to that of the inorganic main component of bone. When producing the artificial bone 90, the hydroxyapatite particles as the raw material are more preferably calcined at 500 to 1000 ° C. The activity of the hydroxyapatite particles calcined at such a temperature is suppressed to some extent, so that sintering unevenness due to rapid progress of sintering or the like is suppressed, and a sintered body having no unevenness in strength can be obtained.

  The osteotomy device 1 is a osteotomy dilator that further expands an incision (osteotomy) where the medial condyle of the tibia is incised. As described above, the bone opening device 1 includes the first blade 2A, the second blade 2B, the angle adjusting mechanism 5, and the scale member 6. Hereinafter, these things which comprise the bone opening device 1 are demonstrated.

  The constituent material of the bone opening device 1 is not particularly limited, and for example, various metal materials such as aluminum, stainless steel, and titanium alloy can be used.

  As shown in FIG. 4, the first blade 2A (one blade) has a pair of first elongated bodies 21A having an elongated shape.

The distal ends 211 of the first elongated bodies 21A are rotatably connected to each other via a connecting portion 22. The connecting portion 22 is, for example, a portion having a pivot structure including a pin-shaped shaft and a bearing rotatably supporting the shaft. Thereby, both the first elongate bodies 21A can be smoothly rotated via the connecting portion 22, that is, they can be approached and separated from each other, and therefore, the rotation angle θ between the first elongate bodies 21A. _21A changes.

Each first elongated member 21A has a thickness t _21A from the middle of the longitudinal direction is a component of tapered shape that gradually decreases along the distal direction. Thereby, the first blade 2A can be easily inserted into the incision of the tibia.

The width W _21A of each first elongate body 21A is constant along the longitudinal direction at a portion inserted into the incision of the tibia. If the width W _21A is gradually reduced in the distal direction at the portion, the thickness t _21A is also gradually reduced, and there is a concern that the strength of each first elongated body 21A may be reduced. Since the width W _21A is constant along the longitudinal direction, it is possible to prevent a decrease in strength. Thus, when the first blade 2A is inserted into the incision of the tibia, the deformation of each first elongated body 21A can be reliably prevented.

  Further, a first thin portion 217 and a second thin portion 218 are formed at the base end 212 of each first elongated body 21A.

In the first thin portion 217, the width _W21A decreases sharply toward the back side of the paper surface in FIG.

In the second thin portion 218, the width _W21A is further reduced toward the near side of the drawing in FIG. 4, and is thinner than the first thin portion 217.

  As shown in FIGS. 1 to 3, in the assembled state, the second blades 2B are used side by side along the first blades 2A.

As shown in FIG. 5, the second blade 2 </ b> B (the other blade) sets a pair of second elongated members 21 </ b> B having an elongated shape and a rotation angle θ ₂₁ </ b> B between the second elongated members 21 </ b> _B. And an angle maintaining member 3 for maintaining.

  The configuration of the second elongated body 21B will be described focusing on the differences from the first elongated body 21A, and the same items will not be described.

The distal ends 211 of the second elongated bodies 21B are rotatably connected to each other via a connecting portion 22. Thus, the rotation angle θ _21B between the second elongated bodies 21B changes. As described later, the rotation angle θ _21B is the same as the rotation angle θ _21A in conjunction with the adjustment of the rotation angle θ _21A between the first elongated bodies 21A in the assembled state. It is adjusted to.

Each second elongate member 21B, the thickness t _21B from the middle of the longitudinal direction is a component of tapered shape that gradually decreases along the distal direction. Thereby, in the assembled state, the second blade 2B can be easily inserted into the incision of the tibia together with the first blade 2A. Incidentally, decreasing rate of the thickness _{t 21B} is the same as the decreasing rate of the thickness _{t 21A} is preferred.

The width W _21B of each second elongated body 21B gradually decreases toward the distal end at a portion inserted into the incision of the tibia, and gradually increases from the middle. As a result, an arch-shaped depression 25 is formed. The recess 25 is for securing a space for facilitating the insertion of the artificial bone 90 into the enlarged portion of the tibia.

  Further, a first thin portion 217 and a second thin portion 218 are also formed at the base end 212 of each second elongated body 21B, similarly to the first elongated body 21A. As shown in FIG. 1, in a state where the first blade 2A and the second blade 2B are juxtaposed, that is, in an assembled state, the first thin portion 217 of the first elongated body 21A and the second The first thin portion 217 of the long body 21B has a symmetrical positional relationship (linear symmetry), and the second thin portion 218 of the first long body 21A and the second long body 21B Has a symmetrical positional relationship (linear symmetry) with the second thin portion 218.

  A female screw 27 is formed in the second elongated body 21B on the upper side in FIG.

  As shown in FIG. 5, the angle maintaining member 3 is formed of a columnar member (rod). A male screw 31 is formed on an outer peripheral portion of the angle maintaining member 3. The male screw 31 is screwed to the female screw 27 of the second elongated body 21B described above (upper side in FIG. 5).

When the angle adjusting member (screw member) 4 of the angle adjusting mechanism 5 is rotated in, for example, one direction in the assembled state, the rotation angle θ _21A between the first elongated bodies 21A is adjusted in a direction to increase. Along with this, the second elongated bodies 21B rotate in a direction in which the second elongated bodies 21B are separated from each other about the connecting portion 22 as a rotation center, that is, in a direction in which the second elongated bodies 21B are opened, and the second elongated bodies 21B are rotated. long element 21B between the rotation angle theta _21B is adjusted to a direction of increasing. After the adjustment of the rotation angle θ _21B , by rotating the angle maintaining member 3 in, for example, one direction, the angle maintaining member 3 moves toward the lower second elongated body 21B in FIG. It hits (contacts) the second elongated body 21B. Thereby, the adjusted rotation angle θ _21B can be reliably maintained (see FIGS. 2 and 3).

  Further, the angle maintaining member 3 has a grip portion 32 which is gripped (pinched) when rotating the angle maintaining member 3 above the male screw 31. The rotation operation of the angle maintaining member 3 can be easily performed by the grip portion 32.

  As shown in FIG. 9, the scale member 6 has a scale plate 61, a large-diameter pin-shaped part 62, a small-diameter pin-shaped part 63, and a grip part 64. As shown in FIGS. 1 to 3, the scale member 6 is mounted on the second blade 2B.

The scale plate 61 is a plate member having an arc shape centered on the connecting portion 22 in an assembled state (see FIGS. 1 to 3), and has an angle scale 611 on its front surface. The angle scale 611 can indicate the rotation angle θ _21B in the assembled state. Thereby, the rotation angle θ _21B can be reliably grasped.

  A large-diameter pin-shaped portion 62 and a small-diameter pin-shaped portion 63 are cantilevered at one end of a scale plate 61 having an arc shape.

  The large-diameter pin-shaped portion 62 protrudes from the rear surface of the scale plate 61 and has a circular cross-sectional shape.

  The small-diameter pin-shaped portion 63 protrudes from the back surface of the scale plate 61 similarly to the large-diameter pin-shaped portion 62, and the length of the projection is the same as the large-diameter pin-shaped portion 62. Further, the cross-sectional shape of the small-diameter pin-shaped portion 63 is circular, and its outer diameter is smaller than the outer diameter of the large-diameter pin-shaped portion 62.

Further, as shown in FIG. 5, in the second blade 2B, a circular large-diameter through-hole 215 and a circular large-diameter through-hole 216 are formed in the lower second elongated body 21B in the figure. . The larger-diameter through hole 215 and a small-diameter through holes 216 are formed through the second elongate member 21B along the width W _21B direction. The large-diameter pin-shaped portion 62 can be inserted (fitted) into the large-diameter through-hole 215, and the small-diameter pin-shaped portion 63 can be inserted (fit) into the small-diameter through-hole 216. it can. Thereby, the scale member 6 is mounted on the second blade 2B. Further, the scale member 6 can be detached from the second blade 2B by grasping the grasping portion 64 and pulling it out as it is.

Further, by inserting the two pin-shaped portions, that is, the large-diameter pin-shaped portion 62 and the small-diameter pin-shaped portion 63, the scale member 6 is reluctant around the large-diameter pin-shaped portion 62 or the small-diameter pin-shaped portion 63. Can be prevented from rotating. Thereby, the rotation angle θ _21B can be accurately grasped. Such a structure having two pin-shaped portions contributes to preventing the rotation of the scale member 6 mounted on the second blade 2B. In addition, since the large-diameter pin-shaped portion 62 and the small-diameter pin-shaped portion 63 have different diameters, it is possible to prevent the scale member 6 from being mounted on the second blade 2B in reverse, ie, the scale. This prevents reverse insertion when the member 6 is mounted.

  The grip portion 64 is located on an extension of the large-diameter pin portion 62 extending to the front side of the scale plate 61. The grip portion 64 is a portion that is gripped when the scale member 6 attached to the second blade 2B is detached. The grip portion 64 is larger than the outer diameter of the large-diameter pin-shaped portion 62 and has a shape that is easy to grip. Thereby, the detachment operation of the scale member 6 can be easily performed.

The angle adjusting mechanism 5 is detachably attached to each first elongated body 21A of the first blade 2A and each second elongated body 21B of the second blade 2B. Then, as shown in FIGS. 1 to 3, in this mounted state, the angle adjusting mechanism 5 connects the first blade 2A and the second blade 2B in a side-by-side relationship, and the positional relationship between the blades. Can be regulated. The angle adjustment mechanism 5 in the mounted state can be adjusted and the rotation angle theta _21A between the first elongate member 21A, and a rotation angle theta _21B between the second elongate member 21B.

  As shown in FIG. 6, the angle adjusting mechanism 5 has a first engaging member 7A, a second engaging member 7B, and an angle adjusting member (screw member) 4.

  In the mounted state, the first engagement member 7A includes one (the upper side in FIGS. 1 to 3) first elongated body 21A of the pair of first elongated bodies 21A, and a pair of second elongated bodies 21A. Of the two long members 21B located on the same side as the first one of the long members 21B (upper side in FIGS. 1 to 3). Can be combined.

  In the mounted state, the second engagement member 7B is provided with a first elongated body 21A (the lower side in FIGS. 1 to 3) of the pair of first elongated bodies 21A, and a pair of first elongated bodies 21A. Of the two long bodies 21B, the other long body 21B located on the same side as the other first long body 21A (the lower side in FIGS. 1 to 3) is collectively placed. Can be engaged.

  Since the first engagement member 7A and the second engagement member 7B have the same configuration except that the engaging portions are different, the first engagement member 7A will be representatively described below.

  As shown in FIGS. 6 to 8, the first engagement member 7 </ b> A has a block-shaped main body 71, a claw 72 and a claw 73 protruding from the main body 71, and a disk-shaped (column-shaped). , And a ball plunger 75 and a ball plunger 76.

  The main body portion 71 is inserted between the first thin portion 217 of the first elongated body 21A and the first thin portion 217 of the second elongated body 21B from the base end toward the distal end. Part. By this insertion, the angle adjusting mechanism 5 is in a mounted state. Then, the mounting state is released, that is, the angle adjusting mechanism 5 can be detached by pulling the angle adjusting mechanism 5 in a direction opposite to the insertion direction. As described above, in the bone opening device 1, when the angle adjusting mechanism 5 is attached and detached, the angle adjusting mechanism 5 is moved forward and backward along the longitudinal direction of the bone opening device 1, and is separated. Can be performed easily and quickly. Further, such an attaching / detaching operation can be performed even in a relatively small space.

  In the main body 71, a claw portion 72 is integrally formed on a side surface of the first elongated body 21A facing the first thinned portion 217, and a first thinned portion of the second elongated body 21B is formed. A claw portion 73 is integrally formed on a side surface facing the portion 217 so as to protrude. As shown in FIG. 7, the claw portion 72 has an “L” shape in a rear view, and forms a groove 721 along the front-rear direction with the main body portion 71. Similarly, the claw portion 73 also has an “L” shape in a rear view, and has a groove 731 along the front-rear direction with the main body portion 71. The second thin portion 218 of the first elongated body 21A is inserted (inserted) into the groove 721, and the second thin portion 218 of the second elongated body 21B is inserted into the groove 731. (Inserted). By such insertion, the angle adjusting mechanism 5 is guided, so that the attaching and detaching operation of the angle adjusting mechanism 5 can be performed stably.

Further, the main body portion 71, the female screw member 74 is rotatably supported by the center axis O ₇₄ around. The central axis _O74 is orthogonal to the front-back direction of the angle adjustment mechanism 5. As shown in FIG. 8, the female screw member 74 has a through hole 741 penetrating in the radial direction. A female screw 742 is formed on the inner peripheral portion of the through hole 741 of one of the two female screw members 74 (upper side in the figure) of the two female screw members 74 in FIG. A female screw 743 whose winding direction is opposite to that of the female screw 742 is formed on the inner peripheral portion of the through hole 741 of the female screw member 74 (lower side in the middle). As described above, one of the female screw 742 and the female screw 743 is a “normal screw”, and the other is a “reverse screw”.

  As shown in FIG. 7, a ball plunger 75 and a ball plunger 76 are installed in the main body 71. The ball plunger 75 is installed so that the ball 751 protrudes to the right side in FIG. 7, and the ball plunger 76 is installed so that the ball 761 protrudes to the left side in FIG. In the first thin portion 217 of the first elongated body 21A, a concave portion 214 with which the ball 751 of the ball plunger 75 is engaged in the mounted state is formed. The first thin portion 217 of the second elongated body 21B is formed with a concave portion 214 with which the ball 761 of the ball plunger 76 is engaged in the mounted state. Then, the ball 751 and the ball 761 are respectively engaged with the concave portions 214, so that the mounted state is maintained. Thereby, for example, it is possible to reliably prevent the angle adjustment mechanism 5 from being detached during use of the bone opening device 1, and thus it is possible to use the bone opening device 1 with confidence. Thus, in the bone opening device 1, the ball plunger 75, the concave portion 214 of the first elongated body 21A with which the ball plunger 75 is engaged, the ball plunger 76, and the second with which the ball plunger 76 is engaged. The concave portion 214 of the elongated body 21B functions as a lock portion for maintaining the mounted state.

  As shown in FIG. 8, the angle adjusting member 4 is provided so as to be collectively inserted into two female screw members 74. The angle adjusting member 4 is formed of a columnar member (rod). A male screw 41 is formed on the outer peripheral portion on one end side (upper side in FIG. 8) from the longitudinal center portion of the angle adjusting member 4, and on the outer peripheral portion on the other end side (lower side in FIG. 8). A male screw 42 is formed. The male screw 41 and the male screw 42 are formed in opposite winding directions. That is, one of the male screw 41 and the male screw 42 is a “normal screw” and the other is a “reverse screw”. The male screw 41 is screwed with the female screw 742 of the female screw member 74 on the male screw 41 side, and the male screw 42 is screwed with the female screw 743 of the female screw member 74 on the male screw 42 side. I have.

  Recesses 43 are formed at both ends of the angle adjusting member 4. A tool such as a hexagon wrench can be fitted into each recess 43. Thereby, the rotation operation on the angle adjusting member 4 can be easily and reliably performed.

Then, from the state shown in FIG. 1, as shown in FIG. 2, by rotating the angle adjusting member 4, for example in one direction (arrow alpha ₄ direction in FIG. 2), the first engagement member 7A and the second The engaging member 7B moves away from each other. Accordingly, the first blade 2A rotates in a direction in which the first elongated bodies 21A are separated from each other around the connecting portion 22 as a rotation center, that is, in a direction in which the first elongated bodies 21A are opened. Go. By this rotation, the rotation angle θ _21A is adjusted in a direction to increase. On the other hand, the second blade 2B also rotates in a direction in which the second elongated bodies 21B are separated from each other around the connecting portion 22 as a rotation center, that is, in a direction in which the second elongated bodies 21B open. . By this rotation, the rotation angle θ _21B is adjusted in a direction to increase.

When the angle adjusting member 4 is rotated in the opposite direction in a state where the angle maintaining member 3 has not been operated yet, the first engagement member 7A and the second engagement member 7B approach each other. Go. Accordingly, the first blade 2A rotates in a direction in which the first elongated bodies 21A approach each other around the connecting portion 22 as a rotation center, that is, in a direction in which the first elongated bodies 21A are closed. Go. By this rotation, the rotation angle θ _21A is adjusted in a direction to decrease. On the other hand, the second blade 2B also rotates in a direction in which the second elongated bodies 21B approach each other around the connecting portion 22 as a rotation center, that is, in a direction in which the second elongated bodies 21B close. . By this rotation, the rotation angle θ _21B is adjusted in a direction to decrease.

In this way, the angle adjusting mechanism 5 can rotate the angle adjusting member 4 to move the first engagement member 7A and the second engagement member 7B closer to or away from each other according to the rotation direction. It is configured as follows. The rotation angles θ _{21A and} θ _21B can be adjusted by approaching or separating the first engagement member 7A and the second engagement member 7B. Accordingly, the angle adjustment mechanism 5 has a configuration in which functions necessary for adjusting the rotation angles θ _{21A and} θ _21B are integrated.

  Next, a method of using the open bone instrument 1 (a state of use) in a high tibial osteotomy (open wedge method) will be described with reference to FIGS. 1 to 3.

[1] As shown in FIG. 1, the bone opening device 1 is in an assembled state in advance. At this time, the bone opening device 1 has a state in which the rotation angle θ _21A and the rotation angle θ _21B are minimum, that is, the first blade 2A and the second blade 2B are in a closed state. Then, the incision made by the incision the medial condyle of the tibia, is inserted in the arrow alpha ₁ direction open bone instrument 1 in the assembled condition from the tip side.

[2] Next, as shown in FIG. 2, rotating the angle adjusting member 4 in the arrow alpha ₄ directions. Accordingly, the first blade 2A is adjusted such that the first elongated bodies 21A are separated from each other in the direction of the arrow _α21A , and thus the rotation angle _θ21A is increased. In addition, the second blade 2B connected to the first blade 2A via the angle adjusting mechanism 5 also separates the second elongated members 21B from each other in conjunction with the movement of the first elongated member 21A. To go. Thereby, the rotation angle θ _21B is also adjusted in the increasing direction. As a result, the incision expands. This extension is performed until the rotation angle θ _21B (rotation angle θ _21A ) reaches a predetermined amount. Note that the rotation angle θ _21B is displayed by an angle scale 611 of the scale member 6 and can be confirmed.

In this way, the bone opening device 1 has a configuration in which the rotation angle θ _21A and the rotation angle θ _21B can be adjusted at the same time as long as the angle adjusting member 4 is rotated. Thus, the incision can be stably and reliably expanded to a desired size.

Further, after adjusting collectively the rotation angle theta _21A and the rotation angle theta _21B, by gripping the grip portion 32 of the angle maintaining member 3, rotating the angle maintaining member 3 in the arrow alpha ₃ direction as it is. As shown in FIG. 2, this rotation operation is performed on the second elongated body 21B provided with the angle maintaining member 3 (the second elongated body 21B on the upper side in the figure). Is performed until the angle maintaining member 3 comes into contact with the long body 21B (the second long body 21B on the lower side in the figure). Thereby, the interval between the second elongated bodies 21B is maintained, and as a result, the rotation angle θ _21B is also maintained.

[3] Then, as shown in FIG. 3, the angle adjusting member 4 is operated to rotate the arrow beta ₄ direction of the opposite direction. Thereby, the first blade 2A approaches in the direction of the arrow β _21A until the first elongate bodies 21A come into contact with each other, so that the rotation angle θ _21A is adjusted in the decreasing direction. It is not necessary to make the first elongated bodies 21A approach each other until they contact each other, and the first elongated bodies 21A may be slightly approached.

In the second blade 2B, the second elongated bodies 21B try to approach each other, but the angle maintaining member 3 restricts the approach between the second elongated bodies 21B. Therefore, in the angle adjustment mechanism 5, the first engagement member 7A moves together with the first elongated body 21A while the engagement of the ball plunger 75 with the first elongated body 21A is maintained. However, the engagement of the ball plunger 76 with the second elongated body 21B is released, that is, the maintenance of the mounted state by the ball plunger 76 is released. Similarly, the second engagement member 7B moves together with the first elongated body 21A while the engagement of the ball plunger 75 with the first elongated body 21A is maintained. However, the engagement of the ball plunger 76 with the second elongated body 21B is released, that is, the maintenance of the mounted state by the ball plunger 76 is released. As described above, in a state where the maintenance of the mounting state of the first blade 2A with respect to the second blade 2B is released, the rotation angle θ _21A is again adjusted by the angle adjustment mechanism 5 independently of the second blade 2B. It will be adjustable. Further, the connection of the first blade 2A to the second blade 2B is released in a state where the maintenance of the state of attachment to the second blade 2B is released.

Thereafter, while maintaining the second blade 2B inserted in the enlarged _portion , the angle adjusting mechanism 5 and the first blade 2A are pulled in the direction of the arrow β2A (along the longitudinal direction of the second blade 2B). T), remove it from the opening section. Withdrawal of the first blade 2A, that is, separation (separation) of the first blade 2A and the second blade 2B, moves the first blade 2A toward the proximal direction with respect to the second blade 2B. It is made possible by doing Accordingly, the first blade 2A can be smoothly removed without applying an excessive force (for example, a force that forcibly spreads the enlarged portion) to the tibia.

  An artificial bone 90 can be inserted and placed in a portion of the enlarged portion from which the first blade 2A has been removed. After placing the artificial bone 90, the angle maintaining member 3 is rotated in the opposite direction to that described above to remove the second blade 2B from the enlarged portion, and the removed portion is replaced with another artificial bone 90. Can be inserted and placed.

As described above, when placing the artificial bone 90 in, for example, the tibia (joint), the angle adjustment mechanism 5 is operated to adjust the rotation angle θ _21A between the first elongated bodies 21A, and the second operation. and an operation for adjusting the rotational angle theta _21B between the elongated body 21B can be stably reliably by performing the. In addition, the separation operation of the first blade 2A and the second blade 2B after the operation can be quickly and accurately performed by operating the angle adjustment mechanism 5. As described above, in the bone opening device 1, the angle adjustment mechanism 5 is an operation in which the operations required for the procedure are integrated, and the operability is excellent.

  As described above, the illustrated embodiment of the bone opening device of the present invention has been described. However, the present invention is not limited to this, and each part constituting the bone opening device may have any configuration capable of exhibiting the same function. Can be replaced with Further, an arbitrary component may be added.

  In addition, although the tibia is used in the above embodiment as the site where the bone opening device is used, the site is not limited to the tibia.

  Further, the scale member is detachably mounted on the second blade, but is not limited thereto, and may be fixed to the second blade. Note that the scale member may be omitted.

1 Bone opening device (opener)
2A 1st blade 2B 2nd blade 21A 1st long body 21B 2nd long body 211 tip part 212 base end part 214 concave part 215 large diameter through hole 216 small diameter through hole 217 first thin part 218 first 2 thin portion 22 connecting portion 25 recess 27 female screw 3 angle maintaining member 31 male screw 32 gripping portion 4 angle adjusting member (screw member)
41, 42 male screw 43 concave portion 5 angle adjusting mechanism 6 scale member 61 scale plate 611 angle scale 62 large diameter pin-shaped portion 63 small diameter pin-shaped portion 64 gripping portion 7A first engaging member 7B second engaging member 71 main body Part 72 claw part 721 groove 73 claw part 731 groove 74 female screw member 741 through hole 742, 743 female screw 75, 76 ball plunger 751, 761 ball 90 artificial bone O ₇₄ central axis t _21A , t _21B thickness W _21A , W _21B width _{α 1, α 21A, α 21B} , α 3, α 4 arrow β _2A, β _21A, β ₄ arrow theta _21A, theta _21B pivot angle

Claims (1)

A first blade having a pair of first elongated bodies whose tip portions are rotatably connected to each other;
A second blade having a pair of second elongated bodies which are provided side by side with the first blade and whose tip portions are rotatably connected to each other;
The first elongated body and the second elongated body are detachably attached to the first elongated body and the second elongated body, and in the attached state, the first blade and the second blade are connected side by side and connected. An angle adjustment mechanism that adjusts a rotation angle between the first elongated bodies and a rotation angle between the second elongated bodies,
A bone opening device comprising:

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