JP5267973B2 - Implant for in-vivo implantation and method for producing the same - Google Patents

Description

  The present invention relates to an implant that is used by being implanted in a body for repairing a bone part of a human body and a method for manufacturing the same.

  In order to repair human body bone damage, such as joint repairs such as hip joint damage of the human body, repair of bones at the time of fracture, and reinforcement repair of weakened bones, these damages have been conventionally repaired using artificial bones. Yes.

  These artificial bones for repair are basically formed of a material having biocompatibility with the human body (see Patent Document 1).

  That is, it is desirable that this type of artificial bone used by being embedded in the body is a material having a low Young's modulus substantially equal to that of a human bone, but since a low Young's modulus alloy has a low strength, a material having a strength similar to that of a human bone. Insufficient points arise in the strength as an artificial bone using, so there is a problem that the thickness and width of the implant must be increased to keep the strength. Therefore, it is difficult to adapt to the target human bone.

  On the other hand, the strength of the support part for artificial joints and lag screws is required. However, if the support part is integrally formed of the above materials, the outer diameter and the wall thickness are increased in order to give the support part a predetermined strength. However, it becomes larger and becomes unsuitable for embedding in the body.

  In particular, in an implant for an artificial joint, a ball portion is fixed to the tip of the support portion, and a joint ball is attached to the ball portion so as to be rotatable with respect to the support portion. The range of the angle is limited by the lower edge of the joint ball coming into contact with the outer peripheral surface of the support part. Therefore, when the thickness of the columnar support part becomes large, the turning angle relative to the support part of the joint ball becomes large. The range of the range is remarkably restricted, causing a problem that the function as an artificial joint is inferior.

Therefore, if the part (for example, the stem part) of the implant that contacts the human bone and the support part are separately formed of different materials with different Young's moduli, the above problems can be solved. It is necessary to connect, so that bacteria may invade the connection part, which causes a serious problem in application to the human body, which is not preferable in practice. In addition, it introduces new problems such as an increase in manufacturing cost.
JP 2007-259955 A

  The present invention makes it possible to form a part that requires a predetermined strength of an implant and a part that is compatible with a human bone from the same material without seams, prevent contamination due to adhesion of bacteria, facilitate manufacturing, and reduce costs. It is an object to achieve the reduction of the above.

  In order to solve the above problems, an implant for internal implantation according to the present invention is an implant that has a predetermined shape and is embedded in the body, and has a human bone joint site that should have affinity for human bone, The human bone joint portion has a low Young's modulus of the same size as a human bone, and the strength portion is higher than the low Young's modulus of the human bone joint portion. The human bone joint portion and the strength portion are integrally formed of the same predetermined material.

  Here, “having affinity with human bones” means that when human bones are subjected to external force, they can be deformed integrally with human bones without any sense of incongruity, and “having the same size as human bones” “Low Young's modulus” means that the Young's modulus is a value that is close to the Young's modulus of the human bone so that it can be deformed integrally with the human bone when the human bone receives an external force. In general, the Young's modulus and hardness of a member have a correlation that the higher the Young's modulus, the higher the hardness. In addition, between the hardness and strength of a member, the higher the hardness, the higher the strength. There is a high correlation. Therefore, the strength part has higher Young's modulus, hardness, and strength than the human bone joint part. Here, the hardness is measured in units of HV, and the strength means that it is hard to be deformed by an external force and is tough, and is a concept wider than the hardness.

  Further, the implant is for an artificial joint, the human bone joint part is a stem part inserted into a human bone, and the strength part is a columnar support part extended from the stem part. Features.

In addition, a ball part is fixed to a tip part of the support part, and a joint ball is attached to the ball part so as to be rotatable with respect to the support part. A range of a swivel angle of the joint ball with respect to the support part is The lower edge portion is limited by contacting the outer peripheral surface of the support portion.

  Further, the implant is for connecting a fractured human bone, wherein the human bone joint site is an intramedullary nail inserted into one human bone, and the strength site is supported by a lag screw screwed into the other human bone It is a part.

  Further, the implant is for connecting a fractured human bone, the human bone joint portion is a plate that is screwed along the outer surface of one human bone, and the strength portion is screwed to the other human bone. It is a support part of a lag screw, It is characterized by the above-mentioned.

  Moreover, the said support part of the said implant is made into the cylinder shape penetrated and supported rotatably through a lag screw.

  The implant is for human bone reinforcement, and includes a plate having a plurality of screw insertion holes for fixing along the human bone to be reinforced, and the human bone joint site is formed by the screw insertion hole. It is a portion other than the periphery, and the strength portion is a portion around the screw insertion hole.

Further, the predetermined material constituting the implant is made of a Ti—Nb—Sn alloy.

  The Ti—Nb—Sn alloy is characterized by being an alloy containing Ti as a base and containing 20 to 40 w% Nb and 1 to 13 w% Sn.

  The strength portion has a hardness higher than that of the human bone joint portion.

  The method for manufacturing an implant according to the present invention is a method for manufacturing an implant having a predetermined shape and embedded in a body, wherein the implant has a human bone joint site that should have affinity with a human bone, and a predetermined strength. The human bone joint portion and the strength portion are integrally formed of the same predetermined material, and a material made of a Ti—Nb—Sn alloy is used. A cold pressing process in which cold forging is performed by inserting between a pair of molds formed into an implant shape, and a heat treatment process in which the strength portion is heat-treated at a predetermined temperature after the cold pressing process. It is characterized by that.

  Further, the predetermined temperature is 240 to 320 ° C.

  Further, the human bone joint portion has a low Young's modulus that is about the same size as a human bone, and the strength portion has a higher Young's modulus than the human bone joint portion.

  Further, the heat treatment step is characterized by heat-treating the strength portion after taking out from the mold what has been cold forged in the cold press step.

  Further, the heat treatment step is characterized in that a part of the mold corresponding to the strength part is heat-treated in a state where the cold forged product in the cold pressing step is placed on the mold. .

  According to the present invention, a part to be fixed in contact with a human bone by a material that is compatible with the human body (low bone modulus human bone joint part) and a part that requires strength (high Young's modulus strength part) are integrated. Therefore, it is not necessary to connect and configure these two parts having different characteristics, and as a result, an extremely safe implant that has no possibility of being contaminated by the invasion of bacteria. Can do.

  In addition, if a Ti—Nb—Sn alloy is used as a raw material, it is originally a material with a low Young's modulus. By performing heat treatment after forging, it is possible to partially achieve a high Young's modulus, and it is possible to easily obtain an implant having a configuration that is compatible with human bones by the same material.

[Embodiment I] Implant for artificial joint (FIGS. 1 to 4)
FIG. 1 shows an artificial joint implant 1A as an example of an implant according to the present invention. The artificial joint implant 1A includes a rod-like stem portion 3 and a stem portion 3 which are inserted into a femur 2 (see FIG. 2). The stem portion 3 and the support portion 8 are integrally formed of the same material. The stem portion 3 and the support portion 8 are bent at an angle θ (30 ° to 50 °). The columnar support portion 8 may be an elliptical columnar support portion 8.

  The ball portion 6 is fixed to the distal end portion of the support portion 8. A joint ball 5 is attached to the ball portion 6 so as to be pivotable with respect to the ball portion 6 (and thus with respect to the stem portion 3). As shown in FIG. 2, the joint ball 5 is embedded in the pelvis 4. As a result, the tem portion 3 can turn with respect to the joint ball 5, and the femur 2 can turn with respect to the pelvis 4. Since the ball portion 6 needs to have sufficient wear resistance with respect to the joint ball 5, the ball portion 6 is formed as a separate member from the stem portion 3 and the support portion 8 and is fixed to the support portion 8 later.

  In this embodiment, the stem portion 3 and the support portion 8 are integrally formed of the same material, but the stem portion 3 has a low Young's modulus as large as a human bone, and the support portion 8 has a high Young's modulus. It is meaningful to do. In general, the Young's modulus and the hardness of the member have a correlation that the higher the Young's modulus, the higher the hardness, and the higher the hardness, the higher the strength. Compared with the stem part 3, it has higher Young's modulus, hardness, and strength.

  As the constituent material of the implant 1A, an alloy of Ti (titanium) -Nb (niobium) -Sn (tin) is used. The Ti—Nb—Sn alloy is an alloy based on Ti, containing 20 to 40% by weight of Nb and 1 to 13% by weight of Sn. Since this alloy can be cold forged at room temperature (for example, 20 to 30 ° C.), it can be formed into the above-described shape by press working according to a process described later. By selecting a Ti—Nb—Sn alloy having such a composition, it becomes easy to manufacture a material having a low Young's modulus similar to that of a human bone by cold forging.

  Since the Ti-Nb-Sn alloy has a low Young's modulus that is similar to the Young's modulus of the human bone, the stem part 3 that is a human bone joint site fixed in contact with the human bone has the properties of the alloy. The support portion 8 which is configured as it is and requires high strength is heat-treated after cold forging to have a higher Young's modulus than the stem portion 3 and is reinforced. Here, for the first time, the inventor has found that it is possible to increase the Young's modulus of a specific part by heat-treating the specific part that should function as a strength part in a predetermined temperature range after cold forging. It is to clarify.

  As the heat treatment means, after forming into a predetermined shape by press working by cold forging, the range of the support portion 8 is heated at a predetermined temperature (240 to 320 ° C.). As a result, only the heat-treated portion can be increased in strength.

  The reason is as follows. In the Ti—Nb—Sn alloy, an extremely fine deformation structure is developed before heating, but the martensite generated by the press treatment after the cold forging described above undergoes reverse transformation to cause an original transformation. Return to the crystal layer. On the other hand, since the reverse transformation temperature is relatively low at around 150 ° C., the strain (transition structure) introduced by the press working hardly recovers and fine precipitation starts, so that the heat-treated portion has high strength. It becomes. When the heat treatment temperature is lower than 240 ° C., as understood with reference to FIG. 3, sufficient hardness required for the support portion 8 cannot be obtained. In addition, when the heat treatment temperature is higher than 320 ° C., as proved experimentally, the composition change occurs in the Ti—Nb—Sn alloy and softens, so that sufficient hardness required for the support portion 8 is obtained. I can't get it.

  As a means for efficiently performing the heat treatment, after press forming by cold forging (pressing), only the die in the forming range of the support portion 8 is heated without opening the die to increase the heat treatment portion. You may make it strengthen.

  In FIG. 3, the relationship between the heat processing temperature of the material 9 which consists of a Ti-Nb-Sn alloy, Young's modulus Ed (GPa), and hardness (HV) is shown. In FIG. 3, for example, a heat source of 300 ° C. was brought into contact with one end 9 a of a rod-shaped material 9 made of a Ti—Nb—Sn alloy having a length of 50 mm, and the temperature of the other end 9 b of the material 9 was set to room temperature 22 ° C. The temperature distribution in the material 9 can be considered that the temperature monotonically decreases from 300 ° C. to 22 ° C. from the one end 9a to the other end 9b with respect to the distance d from the one end 9a that is the heating end of the material 9. Specifically, it can be considered that the temperature of the material 9 decreases linearly with respect to the distance d. FIG. 3 shows the results of measuring the Young's modulus Ed (GPa) and the hardness (HV) of the material 9 with respect to each value of the distance d in such a situation. A dotted line A represents Young's modulus Ed (GPa), and a solid line B represents hardness (HV). As shown in FIG. 3, in the material 9 made of a Ti—Nb—Sn alloy, the Young's modulus Ed (GPa) and hardness (HV) correlate with each other when the heat treatment temperature is increased from room temperature to around 300 ° C. It is observed that it has a monotonically increasing property.

  In FIG. 3, when the distance d is about 25 mm to 50 mm, the heating temperature is about 220 ° C. to room temperature (about 22 ° C.). In this case, the hardness (HV) of the material 9 is almost constant at 200 (HV). The hardness or strength required for the support portion 8 is more preferably higher than 200 (HV). On the other hand, when the distance d is about 20 mm, the heating temperature is about 240 ° C. In this case, the hardness (HV) of the material 9 is 235 (HV), and the hardness is increased by heating. It is recognized that The magnitude of the hardness (HV) of 235 (HV) is a sufficient hardness required for the support portion 8 in consideration of the load of the human body. Thus, referring to FIG. 3, the heat treatment temperature can be selected to be about 240 ° C. or higher in order to obtain the required hardness.

  In FIG. 3, at the other end 9b (distance d is 50 mm), the heating temperature is room temperature (about 22 ° C.). In this case, the Young's modulus Ed (GPa) of the material 9 is about 40 (GPa). It is recognized that it has a Young's modulus comparable to the Young's modulus Ed of the human bone.

  Thus, the stem part 3 and the support part 8 are integrally formed by appropriately selecting the heat treatment temperature after the cold forging and heat-treating only the support part 8 which is a high Young's modulus strength part. It becomes possible.

  Specifically, by setting the heat treatment temperature in the range of 240 to 320 ° C., the hardness of the stem portion 3 can be increased, and as a result, the thickness of the conventional support portion 8 requires 10 mm. It was confirmed that the strength was sufficient even when the thickness was reduced to 7 mm.

  The ability to reduce the thickness of the support portion 8 in the implant 1A can have the following effects. The joint ball 5 is attached to the ball portion 6 so as to be rotatable with respect to the support portion 8. Since the turning angle range of the joint ball 5 is limited by the lower end of the joint ball 5 coming into contact with the outer peripheral surface of the columnar support portion 8, the turning angle range of the joint ball 5 increases as the thickness of the support portion 8 decreases. It is.

  In this embodiment, the thickness of the support portion 8 can be reduced from 10 mm to 7 mm. As a result, the turning angle of the joint ball 5 with respect to the support portion 8 can be set to about 120 degrees to about 134 degrees, and about 14 degrees. The swivel angle was greatly increased.

  About the said press work, as illustrated to FIG. 4 (A)-(E), it passes through the preforming process 12 which processes the round bar raw material 10 which consists of a Ti-Nb-Sn alloy into the straight-bar-shaped raw material 11 of a predetermined shape. The straight rod-shaped material 11 is inserted between the upper and lower molds 13 and 14 and manufactured by cold forging into a predetermined implant shape through the press / bending process 15 shown in FIGS. it can.

  4 (C) to 4 (E), various molds 13 and 14 are used, which are bent in FIG. 4 (C), finely formed in FIG. 4 (D), and in FIG. 4 (E). The straight rod-shaped material 11 shown in FIG. 4 (C) or FIG. 4 (D) is molded to adjust its thickness from the direction where it is tilted 90 degrees. Note that the process illustrated in FIG. 4D may be omitted and the process may proceed from FIG. 4C to FIG.

  When the bending angle θ of the implant 1A is as large as 30 ° to 50 °, for example, when it is difficult to cope with only by forming by cold forging, a process of inserting and bending between bending molds may be added. Good.

  As the round bar-shaped material 10, a Ti—Nb—Sn alloy is melted in a high frequency induction melting furnace or a vacuum arc remelting furnace using a water-cooled copper mold, and formed into a cylindrical shape by hot forging.

  As described above, according to the present embodiment, the stem portion 3 can be made to have a low Young's modulus of the same size as a human bone so as to have an affinity with the human bone, and when the human bone receives an external force, the human bone can be comfortably sensed. Further, the thickness of the support portion 8 can be reduced while securing the necessary strength by making the support portion 8 have a high Young's modulus, and the joint ball 5 with respect to the support portion 8 can be reduced. The swivel angle can be increased.

  Specifically, according to the above embodiment, it is possible to reduce the thickness of the support portion 8 that is 10 mm from the conventional support portion 8 to 7 mm. As a result, the turning angle of the implant 1A is about 120 in the conventional case. The turning angle can be increased to about 134 degrees, and the turning angle can be greatly increased to about 14 degrees.

  Further, since the portions having different Young's moduli of the stem portion 3 and the support portion 8 are integrally formed, there is no seam or the like, and as a result, there is no invasion of bacteria. it can.

[Embodiment II] Implant for fractured human bone connection (FIGS. 5 to 8)
FIG. 5 shows an example in which a fractured human bone connecting implant 1B for repairing a fractured human bone is shown. As shown in FIG. 6, a support portion 19 for inserting and supporting an intramedullary nail 17 (human bone joint portion) to be inserted into one broken human bone 16 a and a lag screw 18 to be screwed into the other human bone 16 b. (Strength part). The lag screw 18 has a male screw 20 at the front end, and a tool engaging portion 21 for rotating with a tool at the rear end. Reference numeral 22 denotes a set screw for preventing the lag screw 18 from loosening.

  The intramedullary nail 17 which is a human bone joint portion of the implant 1B is inserted into the human bone 16a and is fastened by screws 23, 23... And is formed in a round bar shape. In the present embodiment, the term “intramedullary nail” refers to a rod-shaped portion indicated by reference numeral 17 shown in FIG. 5, and the support portion 19 for inserting and supporting the lag screw 18 refers to a portion above the intramedullary nail 17. Yes.

  Also in this implant 1B, the intramedullary nail 17 is made into a human bone joint portion having a low Young's modulus equivalent to that of the human bone 16a by the same manufacturing method as the above-described embodiment (implant 1A for artificial joints), and the support portion 19 has a higher Young's modulus. It is considered as the strength part.

  7 and 8 show an embodiment in which the plate 27 of the fractured human bone connecting implant 1B in FIGS. 5 and 6 is screwed along the outer surface of one of the human bones 16a that has been fractured. In this case, the plate 27 is formed in a narrow plate shape, and a required number of screw insertion holes 25, 25... For fixing the human bone 16a with set screws 24, 24. .

  7 and 8, the plate 27 is a human bone joint site, and the support portion 19 that inserts and supports the lag screw 18 is a strength site. Other configurations are substantially the same as those in FIGS. 5 and 6, and therefore only the corresponding reference numerals are attached.

  According to this embodiment, the intramedullary nail 17 (human bone joint site) can be made to have a low Young's modulus of the same size as the human bone so as to have affinity with the human bone, and when the human bone receives external force Deformation or the like can be performed integrally with the human bone without a sense of incongruity, and the necessary strength can be ensured by making the support portion 19 (strength portion) have a high Young's modulus. Accordingly, the lag screw 18 can be inserted and supported even when the increase in the thickness of the support portion 19 is suppressed.

  Further, the plate 27 (human bone joint site) can be made to have a low Young's modulus of the same size as a human bone so as to have an affinity with the human bone, and when the human bone receives an external force, it is integrated with the human bone without a sense of incongruity. Deformation and the like can be performed, and the supporting portion 19 (strength portion) can be made to have a high Young's modulus to ensure the necessary strength. Accordingly, the lag screw 18 can be inserted and supported even when the increase in the thickness of the support portion 19 is suppressed.

[Embodiment III] Implant for reinforcing human bone (FIG. 9)
FIG. 9 shows an example of a human bone reinforcing implant 1C for reinforcing a weakened human bone, which is formed in an elongated plate shape suitable for fixing along the side surface of the weakened human bone 26, and is a human bone joint site. It is set as the plate 37 which is.

  The plate 37 is provided with a required number of screw insertion holes 29, 29... For inserting screws 28 (round countersunk screws) for fixing to the human bone 26. The screw insertion hole 29 is countersunk for a round countersunk screw as shown in the YY enlarged cross section of FIG. 9A in FIG. 9B.

  The plate 37 is required to be as thin and narrow as possible. However, since the periphery of the screw insertion holes 29, 29... Requires strength, the screw insertion hole 29 is indicated by reference numeral 30 in FIG. The surrounding portion is heated and cured to be a strength portion having a high Young's modulus, and the other portion is a human bone joint portion (stem portion) having a low Young's modulus substantially equal to a human bone.

  Therefore, in order to reinforce the human bone 26 with the implant 1C, the plate 37 is attached to the side surface of the weakened human bone 26, and the human bone 26 is fixed by being screwed into the human bone 26 through the screw insertion holes 29, 29. Can be reinforced.

  In this case, since the plate 37 has a low Young's modulus substantially equal to that of the human bone 26, an excessive load is not applied to the human bone 26.

  The plates 27 and 37 of the implants 1B and 1C shown in FIG. 7, FIG. 8, and FIG. 9 are fixed in contact with the outer surface of the human bone, so that the width is minimized as much as possible so as not to excessively press the periosteum existing on the bone surface. In the case of a plate-like stem, the space for drilling the screw insertion holes 25 and 29 through which screws for fixing to a human bone are reduced, and the screw insertion holes and the side edges of the plates 27 and 37 are desired. The distance from the edge becomes narrow and the strength is inevitably insufficient.

  In this regard, as described above, the peripheral portions of the screw insertion holes 25 and 29 are hardened to form strength portions, and the other portions are made to have plates 27 and 37 having Young's or the like equivalent to human bones, thereby losing the affinity for human bones. The required strength can be retained without any problems.

  When the human bone reinforcing implant 1C having the plate-like plate 37 stem portion is formed, the concave portions 31, 31... Are formed in the side edges between the screw insertion holes 29, 29. It is preferable that the distance L between the screw insertion hole 29 and the side edge is substantially constant in each part so as to disperse the plate 37 so that a force is applied evenly.

  According to this embodiment, the plate 37 (human bone joint site) can be made to have a low Young's modulus of the same size as a human bone so as to have an affinity with the human bone, and when the human bone receives external force, there is no sense of incongruity. Deformation and the like can be performed integrally with the human bone, and the peripheral portion (strength portion) of the screw insertion hole 29 can be made high Young's modulus to ensure necessary strength. Thereby, even if the thickness of the plate 37 is reduced, the strength of the peripheral portion of the screw insertion hole 29 can be secured, and the plate 37 can be thinned.

The side view which shows one Embodiment of the implant for internal implantation by this invention. Explanatory drawing which shows an example of a use condition similarly. A bluff showing the change in Young's modulus of the material used by heating. (A)-(E) are illustration explanatory drawings of the manufacture process of the implant of FIG. The disassembled perspective view which made one part the cross section which shows other embodiment of the implant for internal implantation by this invention. Sectional drawing which shows a use condition same as the above. The perspective view which shows other embodiment of the implant for internal implantation by this invention. Sectional drawing which shows an example of a use condition same as the above. The further another embodiment of the implant for internal implantation by this invention is shown, (A) is a perspective view of a use condition, (B) is a YY expanded sectional view of (A). The perspective view which shows the modification of the implant of FIG.

Explanation of symbols

1A Artificial Joint Implant 1B Fracture Human Bone Joint Implant 1C Human Bone Reinforcement Implant 2, 16a, 16b Human Bone 4 Pelvis 5 Joint Ball 6 Ball Part 3 Stem Part (Human Bone Joint Site)
17 Intramedullary nail (human bone joint site)
27,37 plate (human bone joint site)
8, 19, 30 Supporting part (strength part)
10 Implant Material 11 Straight Bar Material 13, 14 Mold 18 Lag Screw 25, 29 Screw Insertion Hole

Claims (11)

An implant having a predetermined shape and embedded in the body,
A human bone joint site that should have affinity with human bones, and a strength site that should have a predetermined strength,
The human bone joint site has a low Young's modulus of the same size as a human bone,
The strength site has a high Young's modulus higher than the low Young's modulus of the human bone joint site,
The human bone joint portion and the strength portion are integrally formed of the same predetermined material ,
The strength part is formed in a solid state and has the high high Young's modulus, and is located at and near an end part extending outward from an end part of the human bone joint part,
The predetermined material constituting the implant is made of a Ti—Nb—Sn alloy,
The Ti—Nb—Sn alloy is an alloy containing Ti as a base, 20 to 40 w% Nb and 1 to 13 w% Sn.
The predetermined material is inserted between a pair of molds that are molded into a predetermined implant shape and cold pressed, and after the cold pressing, the strength portion is heated at a predetermined temperature,
The implant according to claim 1, wherein the predetermined temperature is 240 to 320C . The implant is for an artificial joint, the human bone joint portion is a stem portion inserted into a human bone, and the strength portion is a columnar support portion extended from the stem portion. The implant for internal implantation according to claim 1. A ball part is fixed to a tip part of the support part, and a joint ball is attached to the ball part so as to be rotatable with respect to the support part, and a range of a turning angle of the joint ball with respect to the support part is below the joint ball. The implant for in-vivo implantation according to claim 2, wherein the edge portion is restricted by contacting an outer peripheral surface of the support portion. The implant is for connecting a fractured human bone, wherein the human bone joint part is an intramedullary nail inserted into one human bone, and the strength part is a lag screw support part screwed into the other human bone The implant for in-vivo implantation according to claim 1, wherein the implant is in-vivo. The implant is for connecting a fractured human bone, the human bone joint portion is a plate that is screwed along the outer surface of one human bone, and the strength portion is a lag screw that is screwed to the other human bone The implant for in-vivo implantation according to claim 1, wherein the implant is an in-vivo implant. 5. The implant for in-vivo implantation according to claim 3, wherein the support portion of the implant has a cylindrical shape that penetrates and supports the lag screw so as to be rotatably inserted. The implant is for reinforcing a human bone, and is composed of a plate having a plurality of screw insertion holes for fixing along the human bone to be reinforced, and the human bone joint site is other than the periphery of the screw insertion hole The implant according to claim 1, wherein the strength portion is a portion around the screw insertion hole. The implant according to claim 1, wherein the strength portion has a hardness higher than that of the human bone joint portion. In the manufacturing method of an implant that has a predetermined shape and is used by being embedded in the body,
The implant has a human osteosynthesis site that should have an affinity with a human bone and a strength site that should have a predetermined strength, and the human osteosynthesis site and the strength site are integrally formed of the same predetermined material. And
A cold pressing step in which cold forging is performed by using a material made of a Ti-Nb-Sn alloy, and inserting the material into a predetermined implant shape between a pair of molds;
A heat treatment step of heat-treating the strength portion at a predetermined temperature after the cold pressing step ;
The predetermined temperature is 240 to 320 ° C.
The Ti—Nb—Sn alloy is an alloy containing Ti as a base, 20 to 40 w% Nb and 1 to 13 w% Sn.
The human bone joint site has a low Young's modulus that is about the same size as a human bone, and the strength portion has a higher Young's modulus than the human bone joint site,
The strength portion is formed in a solid state, has the high high Young's modulus, and is located at and near an end portion extending outward from an end portion of the human bone joint portion. Manufacturing method for implanting human body. The said heat processing process heat-processes the said intensity | strength site | part after taking out what was cold-forged by the said cold press process from the said metal mold | die, The manufacture of the implant for human body embeddings of Claim 9 characterized by the above-mentioned. Method. The heat treatment step, in a state where those are cold forged in the cold pressing step placed in the mold, according to claim, characterized in that the heat treatment portion of the mold corresponding to the intensity site 9. A method for producing an implant for human body according to 9 .

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