JP2009125553A - Implant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an implant which is increased in fixing force of a plate par against an incision area and is capable of miniaturizing an incision area of the skin compared to conventional implants. <P>SOLUTION: The implant 1 is to join the femoral head part 102 of the femur 100 with the femoral diaphysis 104 and includes a lug screw 2 screwed in toward the femoral head part 101, a sleeve part 4 to prevent the lug screw 2 screwed into the femur 100 from being rotated, and a plate part 6 fixed to the femur 100 along a side face of the femoral diaphysis 104. A plurality of fixing screws 46 are penetrated through the plate 6. The fixing screws 46 are screwed into the femoral diaphysis 104. A distal fixing screw 46 farthest from the sleeve part 4 among the plurality of fixing screws 46 is screwed into the femur 100 in a slant direction so as to recede from the sleeve part 4 toward the thread tip end part from the head part of the farthest distal fixing screw 46. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an implant, and more particularly to an implant for use in a femur.

  Conventionally, an implant for a femur used when a femoral neck is fractured is known (see, for example, Patent Document 1). Such an implant is schematically described with reference to FIG. FIG. 15 is a front view of a conventional femoral implant. The implant 200 for the femur 300 shown in FIG. 15 is for fixing the femoral head 304 and the femoral shaft 306 when the femoral neck 302 is cracked or broken. The implant 200 includes a lag screw 202 that is screwed toward the femoral neck 302 and the femoral head 304, and a sleeved plate 204 that is fixed to the femur 300. The plate 204 with the sleeve extends from one end of the plate portion 206 fixed to the femur 300 along the side surface of the femur 300, and is positioned around the lag screw 202 after being screwed. And a sleeve portion 208 embedded in the femur 300. The plate portion 206 is fixed to the femoral shaft 306 by a plurality of fixing screws 210a to 210c.

  By screwing the lag screw 202 into the femur 300, the femoral head 304 and the femoral shaft 306 are fixed in a joined state. Further, the lag screw 202 is prevented from being broken by the sleeve portion 208 of the sleeve-attached plate 204, and the plate portion 206 of the sleeve-attached plate 204 is fixed to the femur 300 by a plurality of fixing screws 210a to 210c. Thus, the lag screw 202 after screwing can be firmly supported.

JP 2004-81681 A

  In the procedure using the implant 200, the screwed lag screw 202 is preferably firmly supported on the femur 300 via the sleeve portion 208 and the plate portion 206.

  In this regard, in order to more firmly fix the plate portion 206 to the femur 300, it is conceivable to extend the plate portion 206 in the longitudinal direction of the femur 300 to increase the number of fixing screws 210a to 210c. However, when the plate portion 206 is extended in the longitudinal direction to increase the number of fixing screws 210a to 210c, it is necessary to widen the incision range for incising the skin and muscles accordingly.

  Specifically, in the example of the implant 200 of FIG. 15, in order to attach the implant 200 to the femur 300, generally, from the intersection X between the axial direction 212 of the sleeve portion 208 and the skin 308, from the sleeve portion 208. It is necessary to incise the skin 308 over the incision range Z between the axial direction 214 of the fixing screw 210 c located farthest and the intersection Y with the skin 308. At this time, the fixing range to the femur 300 by the three fixing screws 210a to 210c of the plate portion 206 is a range W.

  To increase the fixing force of the plate portion 206 to the femur 300, as shown by the phantom line in FIG. 15, when the plate portion 206 is extended to increase the two fixing screws 210d and 210e, A range of fixing to the femur 300 by the fixing screw 210 is a range T. Accordingly, the range T is wider than the fixing range W fixed by the fixing screws 210a to 210c, so that the fixing force can be increased. On the other hand, the incision range that needs to be incised is generally a range U from the intersection point X to the intersection point V between the axial direction 216 of the fixing screw 210e farthest from the sleeve portion 208 and the skin 308. . Therefore, the incision range U becomes larger than the incision range Z when the plate portion 206 is fixed by the three fixing screws 210a to 210c. Since the fracture of the femoral neck is a fracture often seen in the elderly, a less invasive procedure, that is, a procedure with a smaller incision range is desired.

  Accordingly, a first object of the present invention is to provide a femoral implant that can increase the fixing force of the plate portion to the femur with respect to the number of fixing screws to be used, as compared with a conventional femoral implant. Is to provide.

  In addition to the first object, the second object of the present invention can reduce the incision range of the skin and muscle when implanting an implant in a patient as compared with a conventional femoral implant. The object is to provide an implant for the femur.

  In order to achieve the first object, an implant according to the present invention is an implant used for a femur, which has a proximal end portion and a distal screw portion, and is screwed toward a fracture portion of the femur. A lag screw, a sleeve portion disposed around the proximal end portion of the lag screw and embedded in the femur, and a plate portion connected to the sleeve portion and disposed along the longitudinal direction of the femur, The plate portion has a head portion and a screw portion, and has a plurality of through holes through which a plurality of fixing screws for fixing the plate portion to the femur pass, and the first penetration located farthest from the sleeve portion The second through hole, which is located second farthest from the hole and / or the sleeve part, is oblique to the longitudinal direction of the femur so that the fixing screw moves away from the sleeve part from the head part toward the screw part. It is characterized in that it is acceptable to.

  According to the implant of the present invention configured as described above, the first through hole and / or the second through hole has the femur so that the fixing screw moves away from the sleeve portion from the head portion toward the screw portion. Can be received obliquely. Accordingly, when the fixing screw is inserted into the first through hole in an oblique direction, and when the fixing screw is inserted into the second through hole in an oblique direction without using the first through hole, as in the prior art. The plate portion can be supported by the femur in a wider fixing range than when the fixing screw is screwed in the direction perpendicular to the femur. That is, even if the number of fixing screws used is the same, the fixing force of the plate portion to the femur can be increased.

  In this specification, the term “fracture part” refers to a part of the femur that needs to be reinforced, such as when a part of the femur is broken and separated, or when the femur is cracked. Including.

  In the implant, preferably, the plate portion is detachably connected to the sleeve portion.

  According to the implant of the present invention configured as described above, when the implant is attached to the femur, the plate portion and the sleeve portion are separated, and after inserting the sleeve portion from the incision portion of the patient, the plate portion is inserted into the patient's incision. Since it can be inserted from the incision portion, the incision range of the patient's skin and muscle can be reduced. Specifically, when the integrated plate portion and sleeve portion are inserted from the patient's skin, it is necessary to incise the patient's skin and muscle across the entire dimension from the sleeve portion to the plate portion. On the other hand, in the implant of the present invention, since the plate portion and the sleeve portion are detachably connected, the plate portion and the sleeve portion can be inserted into the patient's skin after being separated into smaller parts. Furthermore, as described above, when the fixing screw is inserted in an oblique direction with respect to the femur, the fixing screw is inserted from a position closer to the sleeve portion than when the fixing screw is inserted in a direction perpendicular to the femur. become. These combinations can reduce the incision range of the skin and muscle when implanting the implant in a patient as compared to a conventional femoral implant. Thus, the second object is achieved.

  In the above-described implant, preferably, the first through hole and / or the second through hole of the plate portion has a receiving recess for receiving the head portion of the fixing screw, and the receiving recess is received in a predetermined oblique direction. In order to fix the fixing screw, it has a female screw portion that is screwed into a male screw portion provided in the head portion of the fixing screw.

  According to the implant of the present invention configured as described above, since the receiving recess has the female screw portion, when the fixing screw having the male screw portion is screwed into the femur, the male screw portion of the fixing screw becomes the female screw portion of the receiving recess. And is fixed by screwing. Thereby, a plate part can be firmly fixed to a femur. In this case, the plate part can be fixed to the femur without being pressed against the femur, so that the blood flow around the femur is more reliably prevented than when the plate part is pressed against the femur and fixed. Has the advantage of being able to.

  In this implant, preferably, the receiving through hole of the first through hole and / or the second through hole does not use the female screw part, and the fixing screw having no male screw part is inclined in a direction other than a predetermined diagonal direction. Is acceptable.

  According to the implant of the present invention configured as described above, flexibility in an actual procedure can be ensured. Specifically, for example, when there are a plurality of fracture portions of the femur and a fixing screw is inserted in a predetermined oblique direction, sufficient fixation force for fixing the plate portion to the femur cannot be obtained due to interference with the fracture portion. There is a case. In that case, by changing the angle of the oblique direction through which the fixing screw is inserted, it is possible to avoid interference with the fractured part and to secure the fixing force of the plate part to the femur.

  In this implant, preferably, the head portion of the fixing screw has a convex spherical portion, and the receiving concave portion has a head for fixing a fixing screw having no male screw portion received in an oblique direction other than a predetermined oblique direction. A concave spherical portion that engages the convex spherical portion of the portion.

  According to the present invention configured as described above, the head portion of the fixing screw has a convex spherical portion, and the receiving concave portion has a concave spherical portion that fits the convex spherical portion of the head portion. Is inserted into the through hole in an oblique direction other than a predetermined oblique direction, the convex spherical portion of the head portion is engaged and pressed against the concave spherical portion in the receiving recess. Since the head portion and the receiving recess are engaged with each other by a spherical surface, the plate portion can be stably fixed to the femur. In this case, it is preferable to fix the plate portion to the femur by pressing the plate portion against the femur so as not to disturb the blood flow around the femur.

  In order to achieve the above object, an implant according to the present invention is an implant used for a femur, and has a proximal end portion and a distal screw portion, and is a lug screwed toward a fracture portion of the femur. A screw, a sleeve disposed around the proximal end of the lag screw and embedded in the femur, a plate coupled to the sleeve and disposed along the longitudinal direction of the femur, The plate portion has a plurality of through holes through which the plurality of fixing screws pass, and the fixing screw has a head portion that engages with the plate portion, and a fixing screw. And a plurality of fixing screws having a first fixing screw located farthest from the sleeve portion, and a first fixing screw. The It is characterized in that extending in a direction oblique to the longitudinal direction of the femur away from the sleeve portion from the de part towards the threaded portion.

  According to the implant of the present invention configured as described above, the first fixing screw extends obliquely with respect to the femur so as to move away from the sleeve portion from the head portion toward the screw portion. Therefore, the distal end of the fixing screw extends to a position farther from the sleeve portion than when the fixing screw is screwed in a direction perpendicular to the femur. Therefore, the implant according to the present invention can support the plate portion on the femur in a wider fixing range than the conventional implant. That is, even if the number of fixing screws used is the same, the fixing force of the plate portion to the femur can be increased.

  In the implant, preferably, the plate portion is detachably connected to the sleeve portion.

  According to the implant of the present invention configured as described above, when the implant is attached to the femur, the plate portion and the sleeve portion are separated, and after inserting the sleeve portion from the incision portion of the patient, the plate portion is inserted into the patient's incision. Since it can be inserted from the incision portion, the incision range of the patient's skin and muscle can be reduced. Further, as described above, when the first fixing screw is inserted in an oblique direction with respect to the femur, the fixing screw is inserted from a position closer to the sleeve portion than when the first fixing screw is inserted in a direction perpendicular to the femur. Will be. These combinations can reduce the incision range of the skin and muscle when implanting the implant in a patient as compared to a conventional femoral implant. Thus, the second object is achieved.

  In the above-mentioned implant, preferably, the plurality of fixing screws have a second fixing screw located second most distant from the sleeve portion, and the first fixing point is the first point from the sleeve intersection where the axis of the sleeve portion and the skin covering the femur meet. The longitudinal distance from the first intersection of the fixing screw axis to the skin is equal to or more than the longitudinal distance from the sleeve intersection to the second intersection of the second fixing screw axis and the skin Also short.

  According to the implant of the present invention configured as described above, the first intersection where the axis of the first fixing screw located farthest from the sleeve portion and the skin covering the femur intersects with the first fixing screw. This is the insertion position from the skin when screwed into the femur. Similarly, the insertion position from the skin of the second fixing screw located second farthest from the sleeve portion is the second intersection. Furthermore, if the first intersection point is located on or closer to the sleeve portion than the second intersection point, the incision range will be defined by the second intersection point instead of the first intersection point, The incision range of skin and muscle when implanted in a patient can be reduced.

  In the implant, preferably, the plurality of through holes of the plate portion have a first through hole through which the first fixing screw passes, and the first through hole of the plate portion has the first fixing screw. A receiving recess for receiving the head portion, and the receiving recess is screwed into a male screw portion provided in the head portion of the first fixing screw for fixing the first fixing screw received in a predetermined oblique direction. Has an internal thread portion.

  In this implant, preferably, the receiving concave portion of the first through hole can receive a fixing screw having no male screw portion in an oblique direction other than a predetermined oblique direction without using the female screw portion, and more preferably The head portion of the fixing screw has a convex spherical surface portion, and the receiving concave portion of the first through hole is for fixing a fixing screw having no male screw portion received in an oblique direction other than a predetermined oblique direction. It has a concave spherical portion that engages with the convex spherical portion of the head portion.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[First Embodiment]
An implant according to a first embodiment of the present invention will be described.
FIG. 1 is a side view showing an implant according to a first embodiment of the present invention attached to a femur. The implant 1 of the present embodiment is an implant for jointly fixing the femoral head 102 of the femur 100 fractured at the femoral neck 101 to the femoral shaft 104, and the fracture portion of the femur 100, that is, the femoral bone neck. The lag screw 2 screwed toward the portion 101, the sleeve portion 4 for preventing the rotation of the lag screw 2 screwed into the femur 100, and the femur along the side surface of the femoral trunk 104 connected to the sleeve portion 4 A plate portion 6 fixed to the bone 100. These members are made of a biocompatible material such as a titanium alloy.

  FIG. 2 is an exploded perspective view of the implant 1 according to the first embodiment of the present invention. The lag screw 2 includes a prismatic shaft portion 10 having a hexagonal cross section and a screw portion 12 connected to the tip of the shaft portion 10, and a through hole 13 is formed along the axis 16 </ b> A. A proximal end portion of the shaft portion 10 is a fitting portion 14 that is fitted to the sleeve portion 4. Further, a concave portion 15 for attaching an instrument for screwing the lag screw 2 into the femur 100 is formed at the proximal end of the shaft portion 10. The screw thread of the screw portion 12 is formed with teeth 11 for advancing while threading the femur 100 when screwed into the femur 100. Therefore, the lag screw 2 of the present embodiment is a self-tapping screw. ing. Each dimension of the lag screw 2 is appropriately selected according to the dimension of the femur 100 and the like.

  The sleeve portion 4 is embedded in the femur 100 and is formed at a rotation preventing portion 16 for preventing the rotation of the lag screw 2 screwed into the femur 100 and a proximal end portion of the rotation preventing portion 16. 6 and a connecting portion 18 that is connected to 6. The anti-rotation portion 16 is formed in a cylindrical shape having a through hole 17. The front end portion of the through hole 17 is a fitted portion 19 having a hexagonal cross section corresponding to the cross sectional shape of the fitting portion 14 so that the fitting portion 14 of the lag screw 2 is fitted.

  In addition, the cross-sectional shape of the fitting part 14 and the to-be-fitted part 19 is not restricted to a hexagon, for example, may be polygons, such as a pentagon and a dodecagon, or any of the fitting part 14 and the rotation prevention part 16 A groove may be formed on either side, and a protrusion that engages with the groove may be formed on either side.

  The connecting portion 18 is formed in a plate shape continuously from the base end portion of the rotation preventing portion 16. The connecting portion 18 has flat surfaces 24 and 25, and these flat surfaces 24 and 25 extend obliquely with respect to the cylindrical shaft 16 </ b> A of the detent portion 16 so as to be disposed along the side surface of the diaphyseal portion 104. A protrusion 22 for connecting to the plate portion 6 is formed on the side surface 20 of the connecting portion 18. The protrusion 22 is formed such that a portion of the side surface 20 of the connecting portion 18 near the surface 24 facing the plate portion 6 protrudes from the side surface 20 in a direction perpendicular to the side surface 20.

  The plate portion 6 is an elongated plate-like member having a surface 26 facing the femur 100 and a surface 28 opposite to the surface 26, and the longitudinal direction 6 </ b> A is disposed along the longitudinal direction of the diaphysis 104. The A concave portion 30 for receiving the connecting portion 18 of the sleeve portion 4 is formed on the surface 26 of the plate portion 6. The concave portion 30 is formed at one end portion in the longitudinal direction 6A of the plate portion 6 and opens to the end portion, and is substantially U-shaped when viewed from the plane of the plate portion 6, that is, from a direction perpendicular to the surface 26. . The recess 30 has a bottom surface 32 parallel to the surface 26 of the plate portion 6, and a side surface 34 formed between the bottom surface 32 and the surface 26. The side surface 34 receives the protrusion 22 of the connecting portion 18. The groove portion 36 is formed. In the recess 30, a long hole 38 is formed along the longitudinal direction 6 </ b> A of the plate portion 6, and this long hole 38 is connected to the through hole 17 of the sleeve portion 4 when the plate portion 6 and the sleeve portion 4 are connected. It is formed in a communicating position.

  FIG. 3 is a side sectional view showing a state in which the sleeve portion 4 and the plate portion 6 of the implant 1 according to the first embodiment of the present invention are connected. When the protrusion 22 of the sleeve portion 4 is engaged with the groove portion 36 of the concave portion 30 of the plate portion 6 and the sleeve portion 4 is slid along the longitudinal direction 6A of the plate portion 6, the connecting portion 18 of the sleeve portion 4 becomes the concave portion 30. Are connected to each other. In a state where the sleeve portion 4 is connected to the plate portion 6, the rotation stopper 16 of the sleeve portion 4 is disposed so that the cylindrical shaft 16 </ b> A extends obliquely from the one end of the plate portion 6 with respect to the longitudinal direction 6 </ b> A of the plate portion 6. Is done. At this time, the surface 25 of the connecting portion 18 of the sleeve portion 4 is substantially flush with the surface 26 of the plate portion 6. Further, in a state where the sleeve portion 4 is connected to the plate portion 6, the through hole 17 of the rotation preventing portion 16 of the sleeve portion 4 communicates with the long hole 38 of the plate portion 6.

As shown in FIG. 3, a plurality of (three in this embodiment) through holes 40, 42, 44 are formed in the plate part 6, and the plate part 6 is provided in the through holes 40, 42, 44. A fixing screw 46 (see FIG. 4) for fixing to the femoral shaft 104 passes therethrough.
FIG. 4 is a view showing the fixing screw 46. The fixing screw 46 has a head portion 48 and a thread tip portion 50 on the opposite side. A portion of the head portion 48 on the screw thread tip portion 50 side is a convex spherical portion 52. In addition, a male screw portion 54 is formed at a position farther from the screw thread tip portion 50 than the convex spherical portion 52 of the head portion 48. The fixing screw 46 is made of an appropriate material having biocompatibility, like the plate portion 6 and the like.

  On the other hand, the through holes 40, 42, 44 have receiving recesses 56, 58, 60 for receiving the head portion 48 of the fixing screw 46. The portions of the receiving recesses 56, 58, and 60 that are closer to the surface 26 are concave spherical portions 62, 64, and 66 that fit the convex spherical portion 52 of the head portion 48. Further, female screw portions 68, 70, 72 to which the male screw portion 54 of the fixing screw 46 is screwed are formed in the receiving concave portions 56, 58, 60 at positions closer to the surface 28 than the concave spherical portions 62, 64, 66. ing.

  Here, of the three through holes 40, 42, 44, the two through holes 40, 42 on the side closer to the sleeve portion 4 have the fixing screw 46 substantially perpendicular to the surfaces 26, 28 of the plate portion 6. The fixing screw 46 can be screwed in a direction that can be inserted in the direction, that is, in a direction substantially perpendicular to the longitudinal direction of the femoral shaft 104, and the opening on the surface 26 side of the through holes 40 and 42. Is circular. Further, the central axes 40A and 42A of the through holes 40 and 42 are substantially perpendicular to the surfaces 26 and 28 of the plate portion 6, and when the plate portion 6 is attached to the diaphysis portion 104 of the femur 100, the diaphysis portion 104. It becomes substantially perpendicular to the side surface. The diameter of the opening circle on the surface 26 side of the through holes 40 and 42 is slightly larger than the thread diameter of the thread tip 50 of the fixing screw 46.

  A distal through hole 44 that is farthest from the sleeve portion 4 with respect to the through holes 40 and 42 has a fixing screw 46 at a predetermined angle from a direction substantially perpendicular to the surfaces 26 and 28 of the plate portion 6. It is formed so as to be screwed into the femur 100 along the inclined direction. Therefore, the opening on the surface 26 side of the distal through hole 44 is elliptical. The central axis 44A of the distal through hole 44 is such that the opening on the surface 26 side is farther from the sleeve portion 4 than the opening on the surface 28 side with respect to the central axis 42A of the through hole 42 that is the second farthest from the sleeve portion 4. Is inclined by an angle α.

The female threaded portion 72 of the distal through hole 44 is also formed such that the central axis is inclined by an angle α with respect to the central axis 42A in accordance with the inclination of the distal through hole 44.
When the fixing screw 46 is inserted into the distal through hole 44 and the fixing screw 46 is screwed into the femoral shaft 104, the fixing screw 46 moves away from the sleeve portion 4 from the head portion 48 toward the thread tip 50. And is fixed in an oblique direction with an angle α with respect to the side surface of the femur 100.

Here, the angle α is preferably 10 ° to 70 °, and more preferably 30 ° to 60 °. When the angle α is smaller than 10 °, the thread tip 50 of the fixing screw 46 inserted into the distal through-hole 44 does not move away from the sleeve portion 4 but against the fixing screw 46 inserted into the adjacent through-hole 42. Is not sufficiently spread out. Therefore, the effect of increasing the fixing force of the plate portion 6 expected by inserting the fixing screw 46 obliquely cannot be sufficiently obtained. If the angle α is larger than 70 °, the fixing screw 46 is screwed at a shallow angle with respect to the surface of the femur 100, and thus it is difficult to obtain a desired fixing force.
In the present invention, the angle α is set to 45 °.

Next, a method for attaching the implant 1 to the femur 100 will be described.
5 to 8 are views showing a method of attaching the implant 1 according to the present embodiment.
First, as shown in FIG. 5, in order to define the position where the lag screw 2 is attached from the incision to the diaphysis 104 of the femur 100 toward the bone neck 101 as shown in FIG. Then, the guide pin 108 is inserted so as to pass through the diaphysis 104 and the bone head 102. The insertion of the guide pin 108 is performed using a dedicated instrument so that the guide pin 108 is inserted at a predetermined angle and a predetermined depth with respect to the longitudinal direction of the diaphysis 104.

  Next, reaming is performed along the guide pin 108 to determine the screwing depth of the lag screw 2, and the size of the lag screw 2 and the detent 16 of the sleeve portion 4 can be inserted into the femur 100. Hole 110 is formed.

  As shown in FIG. 6, the guide pin 108 is inserted into the through hole 13 of the lag screw 2, and the lag screw 2 is screwed into the femur 100 along the guide pin 108. Since the screw portion 12 of the lag screw 2 is formed with threading teeth 11, the lag screw 2 advances through the femur 100 while cutting the screw. The lag screw 2 is screwed into the femur 100 by attaching a dedicated instrument to the recess 15 of the lag screw 2.

  After the lag screw 2 is screwed into the femur 100, the sleeve portion 4 is attached to the lag screw 2. As shown in FIG. 7, the sleeve portion 4 is inserted from the cut portion of the skin 106, and the sleeve portion 4 is placed in the hole 110 and embedded in the femur 100. Then, the fitting portion 14 of the lag screw 2 is fitted to the fitted portion 19 of the rotation preventing portion 16. Here, in the lag screw 2, the screw rotation position of the lag screw 2 is adjusted in advance so that the side surface 20 of the connecting portion 18 of the sleeve portion 4 is disposed along the longitudinal direction of the femoral shaft 104.

  When the fitting portion 14 of the lag screw 2 is inserted into the fitted portion 19 of the rotation preventing portion 16, the rotation preventing portion 16 extends around the lag screw 2 and the hexagonal cross-sectional shapes are fitted to each other. Thus, the rotation of the lag screw 2 in the femur 100 is prevented. Further, the rotation preventing portion 16 extends around the base end portion of the lag screw 2 and has a function of reinforcing the base end portion of the lag screw 2, thereby making the lag screw 2 difficult to break.

  After placing the sleeve portion 4 on the femur 100, the plate portion 6 is attached as shown in FIG. First, the plate portion 6 is inserted from the cut portion of the skin 106, the groove portion 36 of the plate portion 6 is engaged with the protrusion 22 of the sleeve portion 4, and the plate portion 6 is slid. As a result, the plate portion 6 is connected to the sleeve portion 4, and the plate portion 6 is disposed on the side surface of the femoral shaft 104. At this time, since the side surface 20 of the connecting portion 18 of the sleeve portion 4 is disposed along the longitudinal direction of the femoral shaft portion 104, the plate portion 6 is also guided by the projection 22 and the longitudinal direction 6A is automatically changed. In the longitudinal direction of the femoral shaft 104.

  Thereafter, the fixing screws 46 are passed through the three through holes 40, 42, 44, and the respective fixing screws 46 are screwed into the diaphysis 104. When screwing the fixing screw 46, first, a hole is made in the femoral shaft 104 with a dedicated tool, and then each fixing screw 46 is penetrated by using appropriate guide means for defining the screwing angle of the fixing screw 46. Screw into the femur 100 through the holes 40, 42, 44. Here, the two fixing screws 46 close to the sleeve portion 4 are perpendicular to the surface 28 of the plate portion 6, that is, along the central axes 40A and 42A of the through holes 40 and 42, with respect to the side surface of the femoral shaft 104. Then, it is screwed into the femoral shaft 104 substantially vertically. On the other hand, the fixing screw 46 (first fixing screw) inserted through the distal through-hole 44 is the screwing direction of the fixing screw 46 (second fixing screw) farthest from the sleeve portion 4, that is, the through-hole 42. Screwed obliquely into the femoral shaft 104 along the central axis 44A of the distal through-hole 44 with an angle α relative to the central axis 42A. Accordingly, the fixing screw 46 inserted through the distal through hole 44 extends from the head portion 48 toward the screw thread tip portion 50 so as to be away from the sleeve portion 4.

  When the respective fixing screws 46 are screwed into the through holes 40, 42, 44, the male screw portions 54 of the fixing screws 46 are screwed into the female screw portions 68, 70, 72 of the respective through holes 40, 42, 44. Is fixed to the plate portion 6. Further, the convex spherical portion 52 of the fixing screw 46 is adapted to the shape of the concave spherical portions 62, 64, 66 of the receiving recesses 56, 58, 60, so that the fixing screw 46 is stably received. 60. Here, the plate portion 6 and the fixing screw 46 are fixed to each other by the male screw portion 54 and the female screw portions 68, 70, and 72, and the fixing screw 46 is screwed into the femoral shaft portion 104, whereby the plate portion 6 is fixed to the femoral shaft portion 104. Secure to. Therefore, the plate portion 6 is firmly fixed to the femoral shaft portion 104 without screwing the fixing screw 46 and pressing the plate portion 6 against the femoral shaft portion 104. When the plate portion 6 is fixed to the femur 100, the plate portion 6 prevents the sleeve portion 4 from rotating and prevents the sleeve portion 4 from coming out of the femur 100, thereby preventing the lag screw 2 from rotating and falling off. To do. Further, rotation and movement of the femoral head 102 with respect to the femoral trunk 104 are prevented.

  Further, since the receiving recesses 56, 58, and 60 are formed in the through holes 40, 42, and 44, the head portion 48 of the fixing screw 46 is accommodated in the receiving recesses 56, 58, and 60. At this time, the head portions 48 of the two fixing screws 46 close to the sleeve portion 4 are completely accommodated in the receiving recesses 56 and 58 and do not protrude from the surface 28 of the plate portion 6. On the other hand, since the fixing screw 46 penetrating the distal through hole 44 is inserted obliquely, a part of the head portion 48 protrudes from the surface 28 of the plate portion 6, but most of it is accommodated in the receiving recess 60. .

  When the doctor wants to adjust the insertion angle of the fixing screw 46 according to the situation during the operation, the fixing screw 46 is inserted into the through holes 40, 42, without using the male screw portion 54 and the female screw portions 68, 70, 72. The fixing screw 46 may be screwed in an oblique direction other than a predetermined oblique direction. Even in that case, the concave spherical portions 62, 64, 66 of the receiving recesses 56, 58, 60 are adapted to the shape of the convex spherical portion 52 of the fixing screw 46, and the fixing screw 46 is stably received.

In this case, since the fixing is performed without using the male screw portion and the female screw portion, it is preferable to use a fixing screw 76 having no male screw portion as shown in FIG. That is, depending on the case, when it is desired to fix by screwing with the female screw portions 56, 58, 60, the fixing screw 48 having the male screw portion 54 is used, and the screwing with the female screw portions 56, 58, 60 is utilized. Without fixing the plate portion 6 to the femur 100, it is preferable to use a fixing screw 76 having no male screw portion.
Further, the fixing screw 76 is preferably inserted at an angle β with respect to the direction B perpendicular to the side surface of the femur 100 so as to move away from the sleeve portion from the head portion toward the thread tip portion. Here, the angle β is preferably set to an angle of 5 ° to 70 °, and more preferably set to an angle of 30 ° to 60 °. Note that the fixing screw is not limited to being inserted obliquely with respect to the direction B perpendicular to the side surface of the femur 100, and the angle β is 0 ° as in the case of the fixing screw 76A indicated by the one-dot chain line in FIG. As such, it may be screwed substantially perpendicular to the side of the femur 100.

Next, the skin incision range necessary for attaching the implant 1 according to the present embodiment to the femur 100 will be described.
FIG. 10 is a view showing an incision range of the skin necessary when the implant 1 according to the present embodiment is attached to the femur 100.
When the lag screw 2 and the sleeve portion 4 are inserted, the insertion position is a sleeve intersection point D, which is an intersection point between the axis 2A of the lag screw 2 (or the cylindrical shaft 16A of the rotation preventing portion 16) and the patient's skin 106. .

  Further, when the two fixing screws 46 close to the sleeve portion 4 are inserted into the respective through holes 40, 42, the insertion positions thereof are respectively the center axes 40A, 42A of the through holes 40, 42 and the skin 106. Intersection points E and F, which are the intersection points. On the other hand, the insertion position of the fixing screw 46 inserted through the distal through hole 44 is an intersection point G that is an intersection point of the central axis 44 </ b> A of the distal through hole 44 and the skin 106. Here, the intersection point G is preferably arranged at the same position as the intersection point F or at a position closer to the sleeve portion 4 than the intersection point F. In this embodiment, the intersection point G is closer to the sleeve portion 4 than the intersection point F. Located in position.

  Therefore, in order to dispose the lag screw 2, the sleeve portion 4, the plate portion 6, and the three fixing screws 46 on the femur 100, it is necessary to cut the skin 106 in the range from the sleeve intersection D to the intersection F that is farthest from each other. There is. This incision range varies depending on the inclination angle α of the fixing screw 46 inserted through the distal through hole 44, the interval between the three fixing screws 46, and the like. In the present embodiment, the intersection point F, which is the insertion position of the fixing screw 46 inserted through the central through hole 42, is more than the intersection point G, which is the insertion position of the fixing screw 46 inserted through the distal through hole 44. Since the fixing screw 46 is screwed in, the incision range of the skin 106 is a range from the sleeve intersection point D to the intersection point F.

  The length dimension of the plate portion 6 is longer than the distance between the sleeve intersection point D and the intersection point F, but when the plate portion 6 is placed on the femur 100, the incised portion from the sleeve intersection point D to the intersection point F is shown. The plate portion 6 may be placed on the femur 100 while being inserted obliquely and connected to the sleeve portion 4. Therefore, it is not necessary to extend the incision range beyond the range from the sleeve intersection point D to the intersection point F.

According to such an embodiment, the following excellent effects can be obtained.
The distal through hole 44 farthest from the sleeve portion 4 is formed in an oblique direction, and the distal most fixing screw 46 is moved away from the sleeve portion 4 from the head portion 48 toward the thread tip 50. Since it is screwed into 100, the arrangement range of the three screw tip portions 50 arranged in the femur 100 is wider than the arrangement range of the three head portions 48. That is, when all the conventional fixing screws are screwed substantially perpendicularly to the longitudinal direction of the femur, the fixing range by the fixing screws is the distal end portion of the fixing screw closest to the sleeve portion 4 and the farthest from the sleeve portion 4. This is a range indicated by a fixed range J in FIG. 10, which is a range between the distal end portions of the fixing screws. On the other hand, according to the present embodiment, the fixing range of the fixing screw 46 includes the screw thread tip 50 of the fixing screw 46 that penetrates the through hole 40 and the screw thread tip of the fixing screw 46 that penetrates the through hole 44. This is the range indicated by the fixed range K in FIG. Therefore, the plate portion 6 can be supported by the femur 100 in a wider range than the conventional implant. Thereby, even if the number of fixing screws to be used is the same, the fixing force of the plate portion 6 to the femur 100 can be increased.

  Since the fixing screw 46 inserted through the distal through hole 44 farthest from the sleeve portion 4 is disposed in an oblique direction, the incision range of the patient's skin 106 can be reduced while ensuring the necessary fixing force. . That is, referring to FIG. 10, when all the fixing screws are conventionally screwed substantially perpendicularly to the femur, the insertion position of the fixing screw farthest from the sleeve portion 4 is the insertion direction of the fixing screw and the skin 106. And the intersection H. Therefore, it is necessary to cut the patient's skin 106 from the sleeve intersection D to the intersection H when the fixing screw is screwed. On the other hand, in the present embodiment, since the fixing screw 46 is screwed in an oblique direction, the insertion position of the fixing screw 46 inserted through the distal through hole 44 is the intersection point G and close to the sleeve portion 4. . Therefore, the incision range of the patient's skin 106 is the farthest intersection point F from the sleeve intersection point D, and the incision range can be made smaller than before.

  Here, the intersection point G, which is the insertion position of the fixing screw 46 inserted through the distal through hole 44, is from the intersection point F, which is the insertion position of the fixing screw 46 inserted through the through hole 42 that is the second most distant from the sleeve portion 4. Also, since the position is close to the sleeve portion 4, the incision range is defined by the intersection point F instead of the intersection point G. Thereby, the incision range of the patient's skin 106 when attaching the implant 1 to the femur 100 can be reduced.

  Further, since the plate portion 6 and the sleeve portion 4 are detachably connected, the plate portion 6 and the sleeve portion 4 are disassembled from the incised portion of the skin 106 when the implant 1 is attached to the femur 100. Can be inserted. Therefore, each part can be inserted from the incision range from the sleeve intersection point D to the intersection point F in FIG. 10 and can be assembled in the vicinity of the femur 100. Therefore, the implant 1 can be attached without increasing the incision range.

  Since the lag screw 2 and the sleeve portion 4 are also separably connected, the mounting operation of the implant 1 is further facilitated. That is, in the case of an implant in which the lag screw and the sleeve portion are integrated, when the lag screw is screwed into the femur, the sleeve portion comes close to the femur together. Therefore, during the screwing operation of the lag screw, an operation of inserting the sleeve portion into the inside from the incised portion of the patient's skin occurs. Further, at the same time when the lag screw is screwed into the femur, the sleeve portion must be moved toward the femur while avoiding interference with muscles and the like. On the other hand, in this embodiment, since the lag screw 2 and the sleeve part 4 are connected so that isolation | separation is possible, insertion of the lag screw 2 and attachment of the sleeve part 4 can be performed separately. Therefore, attachment of the lag screw 2 and the sleeve part 4 can be performed easily.

  Since only the distalmost fixing screw 46 is screwed in an oblique direction, even if the implant 1 is repeatedly subjected to a load due to walking of the patient or the like, the screwing angle of the fixing screw 46 differs. It becomes difficult to come off. Also by this, the fixing force of the plate part 6 can be increased.

  Since the male screw portion 54 is formed in the head portion 48 of the fixing screw 46 and the female screw portions 68, 70, 72 are formed in the through holes 40, 42, 44 of the plate portion 6, the fixing screw 46 is screwed into the femur 100. Then, the male screw portion 54 is screwed into the female screw portions 68, 70, 72 to fix the plate portion 6. Conventionally, in an implant in which a male screw part and a female screw part are not formed, the fixing force of the plate part is obtained by pressing the plate part against the femur with a fixing screw. On the other hand, in this embodiment, since the plate portion 6 is fixed by the head portion 48 of the fixing screw 46, it is possible to fix the plate portion 6 to the femur 100 while maintaining good blood flow around the femur 100. it can.

[Second Embodiment]
Next, an implant according to a second embodiment of the present invention will be described. The implant 400 according to the second embodiment is different from the first embodiment in that the lag screw 2 and the sleeve portion 4 of the implant 1 according to the first embodiment are integrated so as not to be separated.

FIG. 11 is an exploded side view in which a part of the implant 400 according to the second embodiment of the present invention is broken. The implant 400 according to the present embodiment includes a lag screw 402 with a sleeve and a plate portion 6.
The lag screw 402 with the sleeve includes a sleeve portion 404 and a lag screw portion 406. The sleeve portion 404 includes a connecting portion 408 that is connected to the plate portion 6 and has the same configuration as that of the connecting portion 18 of the first embodiment, and a detent portion 410 that holds the lag screw portion 406. A through hole 411 is formed in the rotation preventing portion 410. The through hole 411 includes a circular hole portion 412 having a circular cross section and a hexagonal hole portion 414 on the tip side of a hexagonal cross section having a cross sectional area smaller than that of the circular hole portion 412. A locked portion 414a that locks so that the portion 406 cannot move to the distal end side is configured.

  The lag screw portion 406 includes a shaft portion 416 formed on the proximal end side and a screw portion 418 formed on the distal end side. The shaft portion 416 is located at the most proximal end and is disposed in the through hole 412 of the sleeve portion 404 and has a cylindrical large cylindrical engagement for locking the lag screw portion 406 to the locked portion 414 a of the sleeve portion 404. The stopper 420, the cylindrical small cylindrical portion 422 having a smaller diameter than the large cylindrical locking portion 420, and the distal end side of the small cylindrical portion 422. It is comprised with the hexagonal cylinder part 424 of external shape hexagonal shape.

The large cylindrical locking portion 420 is inserted into the circular hole portion 412 so as to be able to advance and retreat, but is locked by the locked portion 414a of the through hole 411 and cannot move further to the tip side. Yes. Therefore, the lag screw portion 406 is prevented from falling off from the through hole 411 to the tip side when the large cylindrical locking portion 420 is locked to the locked portion 414 of the through hole 411.
The small cylindrical portion 422 has a diameter that can rotate within the hexagonal hole portion 414 of the through hole 411. The outer shape of the hexagonal cylinder portion 424 corresponds to the hexagonal hole portion 414 and is dimensioned to fit into the hexagonal hole portion 414.
Further, since the outer diameter of the screw portion 418 is larger than that of the hexagonal hole portion 414, the lag screw portion 406 is prevented from falling off from the through hole 411 to the proximal end side.
Note that the lag screw portion 406 has a split coupling structure, and is assembled to the sleeve portion 404 in a split state and then coupled to the above-described configuration.

  When attaching the lag screw 402 with the sleeve of such an implant 400 to the femur, first, the large cylindrical locking portion 420 of the lag screw portion 406 is placed at the position of the locked portion 414a of the circular hole portion 412 of the sleeve portion 404. The small cylindrical portion 422 is disposed in the hexagonal hole portion 414. With such an arrangement, the lag screw portion 406 can rotate with respect to the through hole 411.

In this state, when the lag screw portion 406 is screwed into the femur, the lag screw portion 406 can rotate with respect to the sleeve portion 404, and therefore only the lag screw portion 404 can be rotated. After screwing the lag screw portion 406 to a predetermined position, the sleeve portion 404 is pushed along the axis of the lag screw portion 406 to bring the connecting portion 408 into contact with the femur and the hexagonal cylinder portion 424 to the hexagonal hole portion 414. Fit. Since the hexagonal cylinder portion 424 has a hexagonal cross section corresponding to the hexagonal hole portion 414, the lag screw portion 406 is formed by fitting the hexagonal cylinder portion 422 into the hexagonal hole portion 414. Is prevented from rotating. Since the mounting direction of the sleeve portion 404 with respect to the femur is determined, the screwing of the lag screw portion 404 can be rotated so that the hexagonal cylindrical portion 424 of the lag screw portion 404 can be fitted into the hexagonal hole portion 414 of the sleeve portion 404. It is necessary to go to the direction position.
Then, the plate part 6 is connected to the connection part 408 similarly to 1st Embodiment, and the plate part 6 is fixed to a femur by screwing a fixing screw in a femur.

According to such an embodiment, the lag screw portion 406 and the sleeve portion 404 are integrated, and the small cylindrical portion 422 is disposed in the hexagonal hole portion 414 so that the lag screw portion 406 becomes the sleeve portion 404. In contrast, since the lag screw 402 with the sleeve can be attached to the femur, only the lag screw portion 406 can be rotated to facilitate the attaching operation.
In addition, since the hexagonal cylindrical portion 424 is disposed in the hexagonal hole portion 414, the rotation of the lag screw portion 406 is prevented. Therefore, after the lag screw 402 with the sleeve is attached to the femur, Rotation within the bone is prevented, thereby reliably preventing the femoral head from moving relative to the femoral shaft.

  The present invention is not limited to the above embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

For example, in the above-described embodiment, the configuration is such that the lag screw is fitted to the sleeve portion so that the lag screw does not rotate with respect to the sleeve portion. You may have the structure fitted to a sleeve part.
FIG. 12 is a partially cutaway side view showing a modification of the implant of the present invention having such a configuration. Similar to the implant 400 of the second embodiment, the implant 500 includes a plate portion 6 and a lag screw 502 with a sleeve. The sleeve-equipped lag screw 502 has a sleeve portion 504 and a lag screw portion 506, and a through hole 511 of the sleeve portion 504 is located on the distal end side of the cylindrical hole portion 512 and more than the cylindrical hole portion 512. A reduced-diameter hole portion 514 having a small diameter and a circular cross section.

A cylindrical large-diameter locking portion 520 having an outer diameter larger than that of the reduced diameter hole portion 514 and smaller than that of the circular hole portion 512 is formed at the proximal end of the shaft portion 516 of the lag screw portion 506. . Further, the portion other than the locking portion 520 of the shaft portion 516 constitutes a cylindrical small diameter portion 522 having an outer diameter smaller than that of the reduced diameter hole portion 514.
In such a lag screw 502 with a sleeve, the small diameter portion 522 is rotatable within the reduced diameter hole portion 514, and the lag screw portion 506 is rotatable with respect to the sleeve portion 504. Therefore, when the lag screw portion 506 is screwed into the femur, the sleeve portion 504 does not rotate together, so that the screwing operation is facilitated. Further, as in the second embodiment described above, it is necessary to screw the lag screw portion 404 to a rotational position where the hexagonal cylindrical portion 424 of the lag screw portion 404 can be fitted into the hexagonal hole portion 414 of the sleeve portion 404. Disappear. Accordingly, the lag screw portion 506 can be screwed in order to fix the fractured portion of the femur without taking into account the orientation for fitting with the reduced diameter hole portion 514, so Fixing work becomes easy. The implant 500 having such a configuration is particularly useful when used for a patient who does not move rapidly.

  Moreover, in the said 1st and 2nd embodiment, although the plate part and the sleeve part were connected so that isolation | separation was possible, it is not restricted to this, For example, a plate part and a sleeve part may be formed integrally. .

The fixing screw is not limited to the one in which only the fixing screw farthest from the sleeve portion is screwed in an oblique direction. For example, in the above-described embodiment, the central fixing screw is also directed from the head portion toward the thread tip portion. You may screw in the diagonal direction so that it may distance from a sleeve part. Alternatively, for example, as shown in FIG. 13, the most proximal fixing screw 46 from the sleeve portion 4 is screwed in an oblique direction so as to approach the sleeve portion 4 from the head portion 48 toward the thread tip 50. May be. In this case, when the small trochanter 112 portion of the femur 100 is fractured, the small trochanter 112 may be fixed by the fixing screw 46 on the proximal side.
The number of fixing screws, the arrangement of the fixing screws, the interval between the fixing screws, and the like can be arbitrarily selected according to the fracture site, the patient's body shape, and the like.

Further, the number of through holes, the arrangement on the plate portion, and the like can be arbitrarily selected. For example, two or four or more through holes may be formed in the plate portion. Also, it is not necessary for the fixing screws to be inserted through all of the through holes. For example, in order to share parts, a plurality of through holes are formed in the plate portion, depending on conditions such as the patient's body shape and fracture site. Then, the plate portion may be fixed by inserting a fixing screw into a part of the plurality of through holes. Also in this case, the fixing force can be increased by screwing the fixing screw located farthest from the sleeve portion in an oblique direction so as to move away from the sleeve portion from the head portion toward the thread tip portion. Accordingly, the through hole is not limited to a through hole that is farthest from the sleeve portion and can receive the fixing screw in an oblique direction, and at least 2 through the through hole and / or the sleeve portion farthest from the sleeve portion. The second farthest through hole should be able to accept the fixing screw in an oblique direction.
In the case of using a fixing screw that does not have a male screw part, the female screw part may not be formed in the through hole.

  In the above-described embodiment, the implant is described as joining and fixing the fracture site on the proximal end side of the femur. However, as shown in FIG. 14, for example, the implant 600 is arranged on the distal end side of the femur 114. It may be one that fixes the fracture portion of the. Further, as shown in FIG. 14, even when the distal end side of the femur 114 is curved and separated from the implant 600, the male screw portion 120 is formed in the head portion 122 of the fixing screw 116 and the plate portion 118 is penetrated. A female screw portion 124 may be formed in the hole 126, and the male screw portion 120 of the fixing screw 116 may be screwed into the female screw portion 124 of the through hole 126. In this way, the plate portion 118 is fixed to the fixing screw 116 by screwing, and the fixing screw 116 is fixed to the femur 114. Therefore, even if the plate portion 118 is separated from the femur 114, the fixing screw 116 is used. The plate portion 118 can be fixed to the femur 114.

It is a side view which shows the implant by 1st Embodiment of this invention in the state attached to the femur. 1 is an exploded perspective view of an implant according to a first embodiment of the present invention. It is a sectional side view shown in the state which connected the sleeve part and plate part of the implant by 1st Embodiment of this invention. It is a side view which shows the fixation screw of the implant by 1st Embodiment of this invention. It is a figure which shows the attachment method of the implant by 1st Embodiment of this invention. It is a figure which shows the attachment method of the implant by 1st Embodiment of this invention. It is a figure which shows the attachment method of the implant by 1st Embodiment of this invention. It is a figure which shows the attachment method of the implant by 1st Embodiment of this invention. It is a figure which shows the attachment method of the implant by 1st Embodiment of this invention. It is a figure which shows the incision range of the skin required when attaching the implant by 1st Embodiment of this invention to a femur. It is the disassembled side view which fractured | ruptured some implants by 2nd Embodiment of this invention. It is the side view which fractured | ruptured a part which shows the modification of the implant of this invention. It is a figure which shows the modification of this invention. It is a figure which shows another modification of this invention. It is a side view which shows the conventional implant.

Explanation of symbols

1,400,500,600 Implant 2 Lag screw 406,506 Lag screw part 4,404,504 Sleeve part 6,72 Plate part 40,42,44 Through hole 46 Fixing screw 48 Head part 50 Thread tip 52,82 Convex spherical portion 54 Male thread portion 56, 58, 60, 74 Receiving recess 62, 64, 66, 80 Concave spherical portion 68, 70, 72 Female thread portion 100, 110 Femur 101 Bone neck portion 102 Bone head portion 104 Stem portion 106 Skin

Claims (11)

An implant used for the femur,
A lag screw having a proximal end portion and a distal end screw portion and screwed toward a fractured portion of the femur;
A sleeve portion disposed around the proximal end of the lag screw and embedded in the femur;
A plate portion connected to the sleeve portion and disposed along the longitudinal direction of the femur;
The plate portion has a head portion and a screw portion, and has a plurality of through holes through which a plurality of fixing screws for fixing the plate portion to the femur pass.
The first through hole located farthest from the sleeve portion and / or the second through hole located second farthest from the sleeve portion are arranged such that the fixing screw is moved from the head portion toward the screw portion. An implant characterized in that it can be received obliquely with respect to the longitudinal direction of the femur so as to move away from the sleeve portion.   The implant according to claim 1, wherein the plate portion is detachably connected to the sleeve portion.   The first through hole and / or the second through hole of the plate portion has a receiving recess for receiving the head portion of the fixing screw, and the receiving recess fixes the fixing screw received in a predetermined oblique direction. Therefore, the implant according to claim 1 or 2, further comprising a female screw portion that is screwed into a male screw portion provided in a head portion of the fixing screw.   The receiving recess of the first through hole and / or the second through hole receives a fixing screw not having the male screw portion in an oblique direction other than the predetermined oblique direction without using the female screw portion. 4. Implant according to claim 3, characterized in that it is possible.   The head portion of the fixing screw has a convex spherical surface portion, and the receiving concave portion is formed on the head portion in order to fix the fixing screw not having the male screw portion received in an oblique direction other than the predetermined oblique direction. The implant of claim 4, having a concave spherical portion that engages the convex spherical portion. An implant used for the femur,
A lag screw having a proximal end portion and a distal end screw portion and screwed toward a fractured portion of the femur;
A sleeve portion disposed around a proximal end portion of the lag screw and embedded in the femur;
A plate portion connected to the sleeve portion and disposed along the longitudinal direction of the femur;
A plurality of fixing screws for fixing the plate portion to the femur;
The plate portion has a plurality of through holes through which the plurality of fixing screws pass,
The fixing screw has a head portion that engages with the plate portion, and a screw portion that is formed at a distal end portion of the fixing screw and is screwed into the femur through the through hole,
The plurality of fixing screws have a first fixing screw located farthest from the sleeve portion, and the first fixing screw is spaced from the sleeve portion toward the screw portion from the head portion thereof. An implant characterized by extending in an oblique direction with respect to the longitudinal direction of the bone.   The implant according to claim 6, wherein the plate portion is detachably connected to the sleeve portion. The plurality of fixing screws have a second fixing screw located second farthest from the sleeve portion,
The longitudinal distance from the sleeve intersection where the axis of the sleeve portion and the skin covering the femur intersect to the first intersection where the axis of the first fixing screw and the skin intersect is the second fixation from the sleeve intersection. 8. Implant according to claim 6 or 7, characterized in that it is less than or equal to the longitudinal distance to the second intersection where the screw axis and the skin meet. The plurality of through holes of the plate portion have a first through hole through which the first fixing screw passes,
The first through hole of the plate portion has a receiving recess for receiving the head portion of the first fixing screw, and the receiving recess is for fixing the first fixing screw received in a predetermined oblique direction. The implant according to any one of claims 6 to 8, further comprising a female screw portion that is screwed into a male screw portion provided in a head portion of the first fixing screw.   The receiving recess of the first through hole is capable of receiving a fixing screw having no male screw portion in an oblique direction other than the predetermined oblique direction without using the female screw portion. Item 10. The implant according to Item 9.   The head portion of the fixing screw has a convex spherical portion, and the receiving concave portion of the first through hole fixes the fixing screw not having the male screw portion received in an oblique direction other than the predetermined oblique direction. 11. An implant according to claim 10, having a concave spherical portion that engages a convex spherical portion of the head portion.

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