JP2018033616A - Bone fixing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bone fixing system capable of surely fixing a plurality of fixing pins by fixing force controlled to an implant body.SOLUTION: A bone fixing system includes: an implant body 1 having a plurality of transverse holes 1d-1h aligned in an axis line 1x direction; fixing pins 3 formed so as to be inserted into the transverse holes; an engaging structure 2 having a plurality of opening areas 2d-2h mounted on the implant body so as to make an act in a prescribed direction, and formed so as to insert the fixing pin into each of places corresponding to the plurality of transverse holes, and elastic engaging parts 4c-7c each corresponding to the plurality of opening areas, provided so as to be engaged in the prescribed direction with the fixing pins 3 inserted into the opening areas, and provided so as to be elastically deformable by an engaging action in the prescribed direction to the fixing pins inserted into the opening areas; and position setting means 9 making the engaging structure act in the prescribed direction on the implant body, and setting the active position.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a bone fixation system, and more particularly to a device suitable for treating a fracture at the end of a long bone.

  In general, various bone fixation systems are known that are applied to bone for the treatment of bone in orthopedics. As a bone fixing system, a device using various instruments such as a bone plate, a bone screw, a compression hip screw, and an intramedullary nail is known. As one type of this bone fixation system, for example, an intramedullary nail system introduces an intramedullary nail body into the bone marrow to treat fractures of long bones such as the femur and humerus. By fixing the nail body to the bone with a fixing pin (bone screw), the bone having the fracture portion is held in a reduced state, and the fracture portion is healed.

  Conventionally, various bone fixation systems for fixing a fixation pin such as a bone screw to an implant body such as an intramedullary nail body have been used. For example, in the intramedullary nail disclosed in Patent Documents 1 and 2 below, an internal thread is formed in the opening of the intramedullary nail, or a C-shaped ring 22, 24, 26 or a cylindrical shape is formed in the opening. The bone screw can be fixed to the intramedullary nail. On the other hand, what has the structure described in the following patent documents 3 and 4 is proposed as what is excellent in the fixation force of a bone screw rather than such a structure, and is easy to control the said fixation force.

  The intramedullary nail described in Patent Document 3 includes a movable portion (insert) 14 that is screwed into a proximal portion of a main body portion (intramedullary nail main body) 13, and main body insertion holes 131 and 132 of the main body portion 13. An intramedullary fixation system is described in which a main body fixing screw (fixing pin) 11 can be inserted in correspondence with the movable part insertion holes 141 and 142 of the movable part 14. In this intramedullary fixation system, the length of the main body 13 is increased by increasing (positive rotation) the amount of screwing of the male screw (or the rotating member 25) of the movable part 14 screwed into the female screw of the main body 13. When the movable portion 14 is moved to the one side L1, the two fixing screws 11 are sandwiched between the main body portion 13 and the movable portion 14 and are simultaneously fixed. On the other hand, when the movable portion 14 is moved to the other side L2 by reducing the screwing amount (reverse rotation), one fixing screw 11 is fixed, but the other fixing screw is not fixed.

  Patent Document 4 below describes a structure in which a plurality of inserts 124 arranged in the axial direction are accommodated in the proximal portion of an intramedullary nail (intramedullary nail body) 102. When the bolt 120 is screwed into the proximal side of the intramedullary nail 102, the inserts 124 are deformed by axially pressing the plurality of inserts 124, and the width of the opening 128 is larger than the width of the bone screw 110. growing. Further, by removing the bolt 120 from the insert 124, the pressure state is released, the width of the opening 128 of each insert is narrowed, and the bone screw 110 is held from both sides, so that the bone screw 11 is attached to the intramedullary nail 102. Fixed.

JP 2004-223260 A Special table 2007-512875 gazette JP 2011-147469 A International publication pamphlet WO2011 / 002753

  By the way, in the conventional bone fixation system described above, it is possible to prevent the bone union failure due to the dislocation of the implant or the rearrangement of the fracture due to the loosening of the bone screw due to osteoporosis or the like, or to deal with a complicated fracture mode. For some reasons, a plurality of fixing pins (for example, bone screws) may be fixed to an implant body (for example, an intramedullary nail body). In this case, when the above-described structure is used in which the fixing pin is sandwiched between the transverse hole formed in the implant body and the opening formed in the locking structure (for example, insert) disposed in the implant body. However, since high accuracy is required for the relationship between the position of the transverse hole and the position of the opening, or the relationship between the position of the transverse hole and opening and the size of the fixing pin, even if the machining accuracy is slightly deviated, or It is difficult to fix multiple fixing pins properly and reliably because the fixing force tends to fluctuate like one fixing pin is fixed firmly while another fixing pin is fixed loosely. There was a problem.

  Therefore, the present invention solves the above-described problems, and its object is to provide a bone fixation system that can reliably fix a plurality of fixation pins to an implant body with a controlled fixation force. is there.

  In view of such circumstances, the bone fixation system of the present invention is a bone fixation system applied to bone for bone treatment. The bone fixation system includes an implant body having a plurality of axially arranged transverse holes, a fixation pin configured to be inserted through the transverse holes of the implant body, and a predetermined orientation with respect to the implant body. A plurality of opening areas configured to be operably mounted and capable of inserting the fixing pins at locations corresponding to the plurality of transverse holes, and corresponding to each of the plurality of opening areas, the opening area It is provided so as to be able to engage with the fixed pin inserted through the opening in the predetermined direction, and to be elastically deformable by the engaging operation in the predetermined direction with respect to the fixed pin inserted through the opening area. A locking structure having an elastic engagement portion, and a position setting for operating the locking structure in the predetermined direction with respect to the implant body and setting an operating position thereof It includes a stage, a. At this time, the single said elastic engagement part may be provided for every said opening area, ie, for every said fixing pin corresponding to the said opening area, respectively. In addition, a plurality of the elastic engagement portions may be provided for each of the opening areas, that is, for each of the fixing pins corresponding to the opening area.

  In this invention, it is preferable that the said elastic engagement part is separated and protruded from the surrounding part of the said locking structure, and is provided with the front-end | tip part which is a free end. In this case, it is preferable that the elastic engagement portion protrudes in the predetermined direction, and the tip end portion engages with the fixing pin. Moreover, it is preferable that the said elastic engagement part is comprised so that elastic deformation is possible in the aspect in which the shape along the protrusion direction bends when engaging with the said fixed pin.

  In the present invention, the elastic engagement portion is displaced to at least one from the central axis of the fixing pin inserted through the transverse hole and the opening area in accordance with the operation of the locking structure by the position setting means. It is preferable to be provided so as to move toward a place and engage with the fixing pin at the place. In this case, the elastic engagement portion may be disposed and protruded at a position offset with respect to the axis of the implant body. Further, the fixing pin may pass through a position offset with respect to the axis of the implant body.

  When it is configured to be elastically deformable in such a manner that the shape along the protruding direction bends when engaged with the fixed pin, and moves toward a position shifted to at least one from the central axis of the fixed pin When engaging with the fixed pin at the location, the elastic engaging portion may coincide with the moving direction of the elastic engaging portion (axial direction or protruding direction) with respect to the fixed pin. .) And an engaging force having a component in each of the moving direction and the direction orthogonal to the central axis. For example, if the moving direction is a direction parallel to the axis of the implant body, the elastic engagement portion is perpendicular to the axial direction and both the axial direction and the central axis with respect to the fixing pin. And an engaging force having components respectively.

  Further, as described above, when a plurality of the elastic engagement portions are provided for each of the opening areas, that is, for each of the fixing pins corresponding to the opening area, for example, a specific aspect Then, the pair of elastic engagement portions that move toward the positions shifted to both sides from the central axis of the fixing pin inserted through the transverse hole and the opening region, and respectively engage with the fixing pin at the position. It is desirable to have At this time, the elastic engagement portion has a cross-sectional shape in which the thickness along the radial direction of the fixed pin is thinner than the width along the central axis of the fixed pin inserted through the transverse hole and the opening region. Is more desirable.

  In the present invention, it is desirable that the locking structure is configured by arranging a plurality of locking members in contact with each other in the axial direction. Here, the plurality of locking members are different from the first opening member provided with the first elastic engagement portion corresponding to the first opening region and the first opening region. And the second locking member provided with the second elastic engagement portion corresponding to the two open areas.

  In this case, the first locking member provided with the elastic engagement portion, and the second locking member provided with the opening region corresponding to the elastic engagement portion of the first locking member. Are adjacent to each other in the axial direction, and when the first locking member and the second locking member are in contact with each other in the axial direction, the elastic engagement portion is moved by the second locking member. It is preferable to be arranged so as to face the opening area in a state where it can be elastically deformed without being constrained. Here, the second locking member accommodates at least a part of the elastic engagement portion of the first locking member, and the elastic engagement portion is restrained by the second locking member. It is desirable to have an accommodation recess configured to be elastically deformed without being damaged.

  The second locking member includes the second elastic engagement portion, and is adjacent to the second locking member on the opposite side of the first locking member in the axial direction. The third locking member includes a second opening region corresponding to the second elastic engagement portion, and the second locking member and the third locking member are provided. When the member abuts in the axial direction, the second elastic engagement portion is disposed so as to face the second opening region in a state where it can be elastically deformed without being constrained by the third locking member. It is preferable. Also in this case, the third locking member accommodates at least a part of the second elastic engagement portion of the second locking member, and the second elastic engagement portion is It is desirable to have a second receiving recess configured to be elastically deformed without being constrained by the third locking member.

  In addition, it is desirable that the locking member has a column structure portion that transmits the driving force of the position setting means in the axial direction of the implant body without interposing the elastic engagement portion.

  Furthermore, it is desirable that the bone fixation system of the present invention includes a pin engaging member such as a plate, a washer (washer), and a collar used together with the fixing pin. These pin engaging members include an engaged portion such as an insertion hole that engages with a predetermined portion of the fixing pin, for example, a head, and has a function of holding and fixing a bone fragment integrated with the fixing pin. Prepare. In the pin engaging member, in addition to the engaged portion, an auxiliary insertion hole for inserting a screw or pin other than the suture thread or the fixing pin, or a protrusion for engaging with a bone or bone fragment, Can also be provided. The pin engaging member is not limited to a flat plate shape such as a plate or a washer, but may be a curved plate shape that wraps a bone fragment, or may have various shapes other than the plate shape. Good. The pin engaging member is integrally formed with the fixing pin by being extended and formed in a form such as protruding from a portion (for example, the head of a bone screw) that engages with a bone or a bone fragment in a normal fixing pin. May be configured. The pin engaging member preferably has a curved shape that wraps around the bone or bone fragment.

  According to the present invention, it is possible to provide an excellent effect that it is possible to provide a bone fixing system that can reliably fix a plurality of fixing pins to an implant body with a controlled fixing force.

It is each figure which shows the external appearance of each component of embodiment of the bone fixation system which concerns on this invention, Comprising: The top view (a1) and front view (a2) of an intramedullary nail main body (implant main body), Insert (locking structure) Body) schematic plan view (b1), schematic front view (b2) and schematic right side view (b3), side view and cross-sectional view (c) of a bone screw (fixing pin) shown with an elastic engagement part, and bone It is plane explanatory drawing (d) and cross-sectional explanatory drawing (e) which show the dimensional relationship between the axial part of a screw (fixing pin), and an elastic engagement part. It is the longitudinal cross-sectional view (a) which shows the releasing state of embodiment of a bone fixation system, and the base expanded sectional view (b) which shows the fixation state of the embodiment. A schematic exploded perspective view (a) showing a state in which components of an insert (locking structure) arranged in the base part of the embodiment of the bone fixation system are viewed from the oblique base end side and a state seen from the oblique distal end side It is a schematic exploded perspective view (b) shown. It is a perspective view which shows a mode that the embodiment of the bone fixation system was applied to the humerus, and the fracture part was hold | maintained and fixed by the some fixing pin (bone screw) in the humeral head of the proximal end.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Initially, with reference to FIG. 1, the whole structure of the bone fixation system of embodiment which concerns on this invention is demonstrated.

  In this embodiment, as shown in FIG. 1, an intramedullary nail body 1 constituting an implant body, and a latch accommodated in a lumen 1 c formed inside a proximal end portion 1 a of the intramedullary nail body 1. A transverse hole 1d formed in a proximal region near the proximal end portion 1a of the intramedullary nail body 1 in a state where the insert 2 is disposed in the inner cavity 1c of the intramedullary nail body 1 and the insert 2 constituting the structure. 1e, 1f, 1g, and 1h, and a bone screw 3 that constitutes a fixing pin. As shown in FIG. 2 (a), transverse holes 1i and 1j are also formed in the distal region near the distal end 1b of the intramedullary nail body 1.

  The intramedullary nail body 1 has a shape extending from the proximal end 1a to the distal end 1b along the axis 1x. Moreover, it has the lumen | bore 1c opened to the base end part 1a and extended toward the terminal part 1b. The lumen 1c is formed in a shape extending from the proximal end portion 1a into the proximal end side region. In this embodiment, as shown in FIG. 2, the lumen 1c is formed as an axial hole that penetrates to the end portion 1b. The lumen 1c has a large inner diameter in the proximal end region near the proximal end portion 1a, and a small inner diameter in the distal end region near the distal end portion 1b.

  In the present embodiment, the base end (part) and the end (part) of each component are predetermined with respect to a medical proximal (part) and distal (part) for a predetermined application site. Although there is a case where there is a correspondence relationship, the present invention is not limited to this, and the above correspondence relationship is variously set according to various application sites. Moreover, the names of the base end (part) and the end (part) of each component are for convenience, and have no significance over one end (part) and the other end (part).

  The intramedullary nail body 1 is provided with transverse holes 1d, 1e, 1f, 1g, and 1h in the proximal region through which the bone screw 3 can be inserted in the direction intersecting the axis 1x via the lumen 1c. . These transverse holes 1d, 1e, 1f, 1g, and 1h are configured by forming a pair of holes in the wall portion that are disposed opposite to each other on both sides of the lumen 1c. The axis lines 1dx, 1ex, 1fx, 1gx, and 1hx of these transverse holes are set in various directions as long as they intersect the axis line 1x, and as shown in the figure, they are mutually in a plane orthogonal to the axis line 1x. Some of them have axes 1dx, 1ex, 1fx, and 1gx that are orthogonal to, parallel to, or inclined to each other, and some that intersect the axis 1x in the direction of inclination, such as the axis 1hx. Or various transverse directions that are inclined with respect to each other. Further, unlike the illustrated example, the transverse hole may be formed so as to penetrate a position offset from the axis 1x. The central axis of the bone screw (fixing pin) inserted through the transverse hole passes through a position deviated from the axis 1x of the intramedullary nail body 1. By providing such a transverse hole, it is possible to improve the adaptability to various fracture modes by the system.

  An insert 2 that is a locking structure is accommodated in the lumen 1c in the proximal end region. The insert 2 includes a proximal end portion 2a and a distal end portion 2b, and includes a shaft hole 2c penetrating along the axis 2x. The shaft hole 2c is a hole for inserting a guide wire. The insert 2 is provided with opening areas 2d, 2e, 2f, 2g, and 2h corresponding to the transverse holes 1d, 1e, 1f, 1g, and 1h. The axis of the intramedullary nail body 1 of the insert 2 is aligned so that these open areas 2d, 2e, 2f, 2g, 2h are aligned with the transverse holes 1d, 1e, 1f, 1g, 1h of the intramedullary nail body 1. When the positions in the 1x direction are matched, the bone screw 3 described later can be inserted into the transverse hole and the opening area corresponding to each other. The axis 2dx, 2ex, 2fx, 2gx, 2hx of the opening area has a position in the direction of the axis 1x corresponding to the axis 1dx, 1ex, 1fx, 1gx, 1hx of the transverse hole, a penetrating orientation, and a mutual interval.

  As shown in FIG. 2, the insert 2 includes an elastic portion 9A (coil spring) interposed between the proximal end region of the lumen 1c and an inner step portion 1cd formed at the boundary position of the distal end region. ) Is biased toward the base end side in the direction of the axis 1x. An annular groove is formed at a position close to the opening of the proximal end 1a of the lumen 1c of the intramedullary nail body 1, and a holding portion (retaining ring) 9B having an opening at the center is fitted into the annular groove. ing. The holding portion 9B locks the base end portion 2a of the insert 2 and holds the insert 2 biased toward the base end side by the elastic portion 9A within a predetermined range in the direction of the axis 1x. Furthermore, an internal thread 1ca is formed on the inner peripheral surface near the opening of the proximal end 1a of the intramedullary nail body 1, and an operating portion (end cap) 9C provided with an external thread 9cb that can be screwed to the internal thread 1ca. Have When the operation portion 9C is screwed into the female screw 1ca, the drive surface 9ct pushes the proximal end portion 2a of the insert 2 (the portion exposed by the central opening of the holding portion 9B) toward the distal end, so that the insert 2 is elastic. It moves (moves) toward the end side of the axis 1x while pushing and shrinking the elastic portion 9A against the elastic force of the portion 9A. The elastic part 9A, the holding part 9B, and the operation part 9C constitute position setting means 9 for setting the operation position in the direction of the axis 1x of the insert 2 with respect to the intramedullary nail body 1.

  2A shows a released state in which the insert 2 is disposed at an initial position determined by the elastic portion 9A and the holding portion 9B without receiving the driving force of the operation portion 9C, and FIG. Is a fixed state in which the insert 2 is moved (moved) from the initial position to the distal side by the driving force of the operation portion 9C, and a bone screw 3 (not shown) is held between the intramedullary nail body 1 at a predetermined operation position. Is shown. The position setting means 9 of the present embodiment moves the insert 2 toward the end side in the direction of the axis 1x and fixes it at a predetermined operating position.

  The insert 2 is disposed in the lumen 1c in a posture in which the axis 2x is disposed along the axis 1x. At this time, as shown in FIGS. 2 and 3, the insert 2 is constituted by a state in which a plurality of locking members 4, 5, 6, 6, 7, 8 are arranged along the axis 2 x. The plurality of locking members 4 to 8 have the structure shown in FIG. 3, and a driving force received from the operation portion 9C of the position setting means 9 along the axis 2x in a state where they are in contact with each other in the direction of the axis 2x. Constructed to be able to tell the direction.

  The locking member 4 includes a base end portion 4a having a ring-shaped flat surface (which coincides with the base end portion 2a of the insert 2) and a distal end portion on the opposite side along the axis 2x of the base end portion 4a. 4b. The distal end portion 4b is the tip of a pair of elastic engagement portions 4c and 4c that respectively protrude in a direction along the axis 2x from a pair of outer edge portions facing the base end portion 4a. A shaft hole 4d penetrating along the axis 2x is formed inside the base end portion 4a. The shaft hole 4d constitutes a shaft hole 2c of the insert (locking structure) 2 together with shaft holes 5d, 6d, 7d, and 8d described later. The elastic engagement portion 4c has a plate-like cross section along the axis 2x, and protrudes in the direction along the axis 2x. On the outer peripheral side of the base end portion 4a, a ring-shaped held portion 4g that is lowered by a stepped portion is provided, and the held portion 4g faces the opening of the holding portion 9B in the lumen 1c. The inner edge 9ba is fitted, and thereby the insert 2 is held below the holding portion 9B. Note that the held portion 4g engages with the inner edge 9ba provided in the opening of the holding portion 9B (particularly at a position close to the upper opening edge), whereby the directions of the individual axes 1x of the holding portion 9B and the insert 2 are achieved. The size of the holding portion 9B and the insert 2 as a whole is reduced in size in the direction of the axis 1x while ensuring the stability of the holding portion 9B and the holding property of the insert 2 (to save space). ). An arc-shaped band-shaped load transmitting portion 4e is provided in a pair of angular regions on the back side of the base end portion 4a and the held portion 4g and where the pair of elastic engagement portions 4c are not formed.

  The locking member 5 has a base end portion 5a and a distal end portion 5b, and the base end portion 5a has a pair of flat surfaces that come into contact with the load transmitting portion 4e of the locking member 4. The base end portion 5a is an end surface portion divided into two parts by providing an accommodation recess 5j for receiving the pair of elastic engagement portions 4c with a margin so as not to restrain the pair. The locking member 5 has a pair of elastic engagement portions 5c, 5c, a terminal portion 5b provided at the tip of these elastic engagement portions 5c, and a shaft hole 5d penetrating along the axis 2x. ing. Moreover, it has the opening area 2d opened in the direction orthogonal to the said accommodation recessed part 5j. As described above, the opening area 2d includes the axis 2dx extending on a plane orthogonal to the axis 1x, and is disposed at a position corresponding to the transverse hole 1d of the intramedullary nail body 1 so that the bone screw 3 is inserted. to enable.

  With the load transmitting portion 4e of the locking member 4 in contact with the base end portion 5a of the locking member 5, the receiving recess 5j of the locking member 5 is a pair of elastic engagement portions 4c, 4c of the locking member 4. And the elastic engagement portion 4c can be elastically deformed without being restrained by the locking member 5. At this time, the mutually opposing inner side surfaces of the pair of elastic engagement portions 4c, 4c are arranged to face the opening region 2d from both sides. In this locking member 5, the elastic engagement portion 5c is a timepiece centered on the axis 2x when viewed from the base end 2a side to the end portion 2b along the axis 2x with respect to the housing recess 5j. It is formed at a position rotated around an angle θ1 (for example, 30 degrees). For this reason, the pair of elastic engagement portions 5c, 5c of the locking member 5 is centered on the axis 2x when viewed in the same direction as described above with respect to the elastic engagement portion 4c of the locking member 4. Thus, it is formed at a position rotated by an angle θ1 in the clockwise direction.

  The locking member 6 has a proximal end portion 6a and a distal end portion 6b, and the proximal end portion 6a has a pair of flat surfaces that come into contact with the load transmitting portion 5e of the locking member 5. The base end portion 6a is an end surface portion divided into two parts by providing an accommodation recess 6j for receiving the pair of elastic engagement portions 5c with a margin so as not to restrain the pair. The locking member 6 has a pair of elastic engagement portions 6c, 6c, a terminal portion 6b provided at the tip of these elastic engagement portions 6c, and a shaft hole 6d penetrating along the axis 2x. ing. Moreover, it has the opening area 2e opened in the direction orthogonal to the said accommodation recessed part 6j. As described above, the opening area 2e includes the axis 2ex extending on a plane orthogonal to the axis 1x, and is disposed at a position corresponding to the transverse hole 1e of the intramedullary nail body 1 so that the bone screw 3 is inserted. to enable.

  The locking member 6 rotates clockwise from the posture shown in FIG. 3 when viewed from the proximal end side to the distal end side due to the angular relationship between the receiving recess 5j of the locking member 5 and the elastic engagement portion 5c. Is engaged with the locking member 5 in a posture rotated by an angle θ1. Therefore, the axis 2ex of the opening area 2e is in a posture rotated clockwise by an angle θ1 when viewed in the same direction with respect to the axis 2dx of the opening area 2d provided in the locking member 5.

  With the load transmitting portion 5e of the locking member 5 in contact with the base end portion 6a of the locking member 6, the receiving recess 6j of the locking member 6 is a pair of elastic engagement portions 5c, 5c of the locking member 5. And the elastic engagement portion 5c can be elastically deformed without being restrained by the locking member 6. At this time, the mutually opposing inner side surfaces of the pair of elastic engagement portions 5c, 5c are arranged to face the opening area 2e from both sides. In this locking member 6, the elastic engaging portion 6 c has a timepiece centered on the axis 2 x when viewed from the base end 2 a side to the end portion 2 b along the axis 2 x with respect to the housing recess 6 j. It is formed at a position rotated by an angle θ2 (for example, 60 degrees). For this reason, the pair of elastic engagement portions 6c, 6c of the locking member 6 is centered on the axis 2x when viewed in the same direction as described above with respect to the elastic engagement portion 5c of the locking member 5. Thus, it is formed at a position rotated clockwise by an angle θ2.

  Another locking member 6 is arranged on the end side of the locking member 6. The distal-side locking member 6 also has a proximal end portion 6a and a distal end portion 6b, and the proximal end portion 6a has a pair of flat surfaces that come into contact with the load transmitting portion 6e of the proximal-side locking member 6. . The base end portion 6a is an end surface portion divided into two parts by providing an accommodation recess 6j for receiving the pair of elastic engagement portions 6c with a margin so as not to restrain the pair. The locking member 6 has a pair of elastic engagement portions 6c, 6c, a terminal portion 6b provided at the tip of these elastic engagement portions 6c, and a shaft hole 6d penetrating along the axis 2x. Yes. Moreover, it has the opening area 2f opened in the direction orthogonal to the said accommodation recessed part 6j. As described above, the open area 2f includes the axis 2fx extending on a plane orthogonal to the axis 1x, and is disposed at a position corresponding to the transverse hole 1f of the intramedullary nail body 1 so that the bone screw 3 is inserted. to enable.

  In the state where the load transmitting portion 6e of the locking member 6 on the proximal end is in contact with the proximal end portion 6a of the locking member 6 on the distal side, the receiving recess 6j of the locking member 6 on the distal side is on the proximal side. The pair of elastic engagement portions 6c, 6c of the locking member 6 are accommodated, and the elastic engagement portion 6c can be elastically deformed without being constrained by the locking member 6 on the end side. At this time, the inner surfaces of the pair of elastic engagement portions 6c, 6c of the locking member 6 on the base end side are arranged so as to face the opening region 2f from both sides.

  Note that the distal-side locking member 6 has a distal end from the proximal end side according to the angular relationship between the receiving recess 6j and the elastic engagement portion 6c of the proximal-side locking member 6 from the posture shown in FIG. When viewed to the side, the base member is engaged with the locking member 6 on the base end side in a posture rotated clockwise by an angle θ2. Therefore, the axis 2fx of the opening area 2f is rotated in the clockwise direction by an angle θ2 when viewed in the same direction with respect to the axis 2ex of the opening area 2e provided in the locking member 6 on the base end side. Become. Accordingly, the axis 2fx assumes a posture rotated by an angle θ1 + θ2 (90 degrees in the illustrated example) clockwise when viewed in the same direction with respect to the axis 2dx of the opening area 2d.

  In the locking member 6 on the distal side, the elastic engagement portion 6c has the axis 2x when viewed from the proximal end 2a side toward the distal end 2b along the axis 1x with respect to the housing recess 6j. The center is formed at a position rotated clockwise by an angle θ3 (for example, 60 degrees, the same as the angle θ2 in the illustrated example). Therefore, when the pair of elastic engaging portions 6c, 6c of the locking member 6 on the distal side is viewed in the same direction as described above with respect to the elastic engaging portions 6c of the locking member 6 on the proximal end side. In addition, it is formed at a position rotated by an angle θ3 clockwise around the axis 2x.

  The locking member 7 has a proximal end portion 7a and a distal end portion 7b, and the proximal end portion 7a has a pair of flat surfaces that come into contact with the load transmitting portion 6e of the locking member 6 on the distal end side. The base end portion 7a is an end surface portion divided into two by being provided with an accommodation recess 7j for receiving the pair of elastic engagement portions 6c with a margin so as not to restrain the pair. The locking member 7 has a pair of elastic engagement portions 7c, 7c, a terminal portion 7b provided at the tip of these elastic engagement portions 7c, and a shaft hole 7d penetrating along the axis 2x. ing. Moreover, it has the opening area 2g opened in the direction orthogonal to the said accommodation recessed part 7j. As described above, the opening area 2g includes the axis 2gx extending on a plane orthogonal to the axis 2x, and is disposed at a position corresponding to the transverse hole 1g of the intramedullary nail body 1 so that the bone screw 3 is inserted. to enable.

  In the state where the load transmitting portion 6e of the locking member 6 on the distal side is in contact with the base end portion 7a of the locking member 7, the receiving recess 7j of the locking member 7 is a pair of elastic members of the locking member 6 on the distal side. The engaging portions 6 c and 6 c are accommodated, and the elastic engaging portion 6 c is elastically deformed without being restrained by the locking member 7. At this time, the mutually opposing inner side surfaces of the pair of elastic engaging portions 6c, 6c of the locking member 6 on the end side are arranged so as to face the opening region 2g from both sides.

  Note that the locking member 7 is viewed from the proximal end side to the distal end side from the posture shown in FIG. 3 depending on the angular relationship between the receiving recess 6j and the elastic engagement portion 6c of the locking member 6 on the distal side. When engaged, it engages with the locking member 6 on the end side in a posture rotated clockwise by an angle θ3. Accordingly, the axis 2gx of the opening area 2g is rotated by an angle θ3 clockwise when viewed in the same direction with respect to the axis 2fx of the opening area 2f provided on the terminal side locking member 6. . Accordingly, the axis 2gx is rotated by an angle θ1 + θ2 + θ3 (150 degrees in the illustrated example) clockwise when viewed in the same direction with respect to the axis 2dx of the opening area 2d.

  In this locking member 7, the elastic engagement portion 7c is a timepiece centering on the axis 2x when viewed from the base end 2a side to the end 2b side along the axis 1x with respect to the housing recess 7j. It is formed at a position rotated around an angle θ4 (for example, 30 degrees). For this reason, the pair of elastic engaging portions 7c, 7c of the locking member 7 is the axis 2x when viewed in the same direction as described above with respect to the elastic engaging portion 6c of the locking member 6 on the distal side. Is formed at a position rotated clockwise by an angle θ4.

  The locking member 8 has a proximal end portion 8a and a distal end portion 8b, and the proximal end portion 8a has a pair of flat surfaces that come into contact with the load transmitting portion 7e of the locking member 7. The base end portion 8a is an end surface portion divided into three parts by providing an accommodation recess 8j for receiving the pair of elastic engagement portions 7c with a margin so as not to restrain the pair. The locking member 8 is provided with a shaft hole 8d penetrating along the axis 2x and an opening region 2h that opens in a direction orthogonal to the housing recess 8j. As described above, the opening area 2h includes the axis 2hx that is inclined with respect to the plane orthogonal to the axis 2x, and is disposed at a position corresponding to the transverse hole 1g of the intramedullary nail body 1 so that the bone screw 3 Can be inserted.

  With the load transmitting portion 7e of the locking member 7 in contact with the base end portion 8a of the locking member 8, the receiving recess 8j of the locking member 8 is a pair of elastic engagement portions 7c, 7c of the locking member 7. And the elastic engagement portion 7c can be elastically deformed without being restrained by the locking member 8. At this time, the mutually opposing inner side surfaces of the pair of elastic engaging portions 7c, 7c of the locking member 7 are arranged so as to face the opening area 2h from both sides.

  When the locking member 8 is viewed from the proximal end side to the distal end side from the posture shown in FIG. 3 according to the angular relationship between the receiving recess 7j of the locking member 7 and the elastic engagement portion 7c. The locking member 7 is fitted in a posture rotated clockwise by an angle θ4. For this reason, the axis 2hx of the opening area 2h is in a posture rotated clockwise by an angle θ4 when viewed in the same direction with respect to the axis 2gx of the opening area 2g provided in the locking member 7. Therefore, the axis 2hx is rotated by an angle θ1 + θ2 + θ3 + θ4 (180 degrees in the illustrated example) clockwise when viewed in the same direction with respect to the axis 2dx of the opening area 2d.

  In this locking member 8, the elastic engagement portion is not formed, and the end portion 8b configured as a shaft portion having a smaller diameter than the other portion protruding toward the end side along the axis 2x is formed. It is the terminal part 2b. A longitudinal groove 8k extending along the axis 2x is formed on the outer periphery of the large-diameter portion (proximal end portion) other than the distal end portion 8b of the locking member 8, and the intramedullary nail body 1 is formed in the longitudinal groove 8k. The inner end portion of the locking pin 8p (see FIG. 2) fixed to is fitted. This prevents the locking member 8 from rotating around the axis 1x in the lumen 1c, but is configured to be slidable in the direction along the axis 1x. Further, an annular step surface is formed between the distal end portion 8b and the other outer diameter portion (base end side portion), and this step surface serves as a supported portion 8g with which the elastic portion 9A abuts. The rotation restriction by the vertical groove 8k and the locking pin 8p also restricts the rotation of the locking members 4-7 around the axis by the fitting structure of the elastic engagement parts 4c-7c and the receiving recesses 5j-8j. The rotation of the entire insert 2 around the axis 1x is restricted.

  The insert 2 is configured by stacking the locking members 4, 5, 6, 6, 7, and 8 as described above. At this time, between the base end portion 4a of the locking member 4 on the most proximal side and the load transmitting portion 4e, between the base end portion 5a of the locking member 5 and the load transmitting portion 5e, the base of the locking member 6 is provided. Between the end portion 6a and the load transmitting portion 6e, between the base end portion 7a of the locking member 7 and the load transmitting portion 7e, between the base end portion 8a of the locking member 8 on the most distal side and the supported portion 8g. In the middle, column structures 4f, 5f, 6f, 7f, and 8f that extend continuously in the direction along the axis 2x in each locking member are provided. In addition, that said support | pillar structure part is extended means that it extends without interposing a space | gap, such as an opening area and an accommodation recessed part. Even if the receiving recesses 5j, 6j, 7j, and 8j and the opening areas 2d, 2e, 2f, 2g, and 2h are provided by the support structure portions 4f, 5f, 6f, 7f, and 8f as described above, the operation is performed. The driving force of the portion 9C can be reliably transmitted to the entire insert 2 without being attenuated, and as a result, each elastic engagement portion 4c, 5c, 6c, 7c can be reliably engaged with the bone screw 3. it can.

  The plurality of elastic engagement portions 4c, 5c, 6c, 6c, and 7c provided in the insert 2 have the same shape in the corresponding positions in the opening areas 2d, 2e, 2f, 2g, and 2h of the insert 2, respectively ( Structure). This is because any of the elastic engagement portions 4c, 5c, 6c, 6c, and 7c has the transverse holes 1d, 1e, 1f, 1g, and 1h of the intramedullary nail body 1 and the corresponding opening regions 2d, In order to enable the bone screw 3 to be simultaneously fixed to the intramedullary nail body 1 in the same manner by engaging with the shaft portion 3b of the bone screw 3 inserted through 2e, 2f, 2g, and 2h. It is.

  As shown in FIG. 2, when the operation portion 9C is screwed into the female screw 1ca, the drive surface 9ct comes into contact with the proximal end portion 4a of the locking member 4 exposed in the opening of the holding portion 9B, and the insert 2 is moved in the axial direction. Push down toward the end of the. Then, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c operate toward the end side in the direction of the axis 1x, as shown in FIGS. 1 (c), (d), and (e), It relates to the transverse hole 1d, 1e, 1f, 1g, 1h of the intramedullary nail body 1 and the shaft part 3b of the bone screw 3 inserted through the corresponding opening areas 2d, 2e, 2f, 2g, 2h. And elastically deforms in such a manner that the shape along the protruding direction is bent. As a result, the bone screw 3 receives a pressing force toward the end side in the direction of the axis 1x from the elastic engagement portions 4c, 5c, 6c, 6c, and 7c, and is directed toward the inside in the radial direction of the shaft portion 3b. Receives elastic restoring force (clamping pressure). On the other hand, since the bone screw 3 is inserted into the transverse holes 1d to 1h of the intramedullary nail body 1, it is supported from the end side in the direction of the axis 1x by the opening edges of the transverse holes 1d to 1h. Therefore, the bone screw 3 is fixed to the intramedullary nail body 1 by being sandwiched between the elastic engagement portions 4c, 5c, 6c, 6c, and 7c and the opening edges of the transverse holes 1d to 1h. The

  The elastic engagement portions 4c, 5c, 6c, 6c, and 7c are set (moved) by the position setting means 9 in a predetermined direction (terminal side in the direction of the axis 1x) and set to a predetermined operating position. The bone screw 3 may be engaged with the bone screw 3 as described above to fix the bone screw 3 to the intramedullary nail body 1. Therefore, the elastic engagement portion is not limited to the one extending along the axis 2x as in the illustrated example, but may be formed so as to extend in a direction perpendicular to the axis or in an inclined direction. Moreover, it is not limited to the one extending toward the distal end in the direction of the axis 2x as in the illustrated example, and may conversely extend toward the proximal end. Furthermore, it is not limited to one having a tip portion that is not constrained at the protruding tip as shown in the illustrated example, and includes, for example, a bridge-like structure that extends from a certain point and connects to another point, and the intermediate portion is a bone. You may contact | abut to the screw | thread 3.

  Even when the elastic engagement portions 4c, 5c, 6c, 6c, and 7c are provided with a tip portion that is a free end as in the illustrated example, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c not only project linearly, Shape), curved, or refracted. That is, the protruding direction is not limited to one and may not be a fixed direction. In any case, the shape (structure) that protrudes separately from the peripheral portion of the insert 2 and has a distal end portion that is a free end facilitates elastic deformation and can be engaged with the bone screw 3 in various ways. Since it becomes possible, the bone screw 3 can be fixed between the intramedullary nail body 1 in various ways. Even in this case, the contact point with the fixing pin (bone screw 3) does not need to be the tip of the elastic engagement portions 4c, 5c, 6c, 6c, and 7c as shown in the illustrated example. It may be an intermediate part.

  When the elastic engagement portions 4c, 5c, 6c, 6c, and 7c are engaged with the bone screw 3, at least a part thereof is elastically deformed. For example, in the case of the present embodiment, as shown in FIGS. 1D and 1E, when the insert 2 moves to the end side (the lower side in the drawing) of the axis 1x, a pair of elastic engagement portions 4c. , 5c, 6c, 6c, 7c, the distal end portions (end portions 4b, 5b, 6b, 6b, 7b) are in contact with the positions shifted to both sides from the central axis 3x of the bone screw 3, and the insert 2 is further the same. When operated in the direction, each elastically deforms in such a manner that the shape along the protruding direction is bent outward in the radial direction of the shaft portion 3b of the bone screw 3, that is, on both the left and right sides in the drawing. That is, in this embodiment, when the insert 2 moves in a predetermined direction (the end side in the direction of the axis 1x), the shape of the elastic engagement portion along the protruding direction is bent when engaged with the bone screw 3. Therefore, the amount of elastic deformation in the predetermined direction is small, and the elastic deformation is mainly performed in a direction other than the predetermined direction (outside in the radial direction of the bone screw 3). However, in the present invention, on the contrary, the elastic deformation in the predetermined direction is dominant, and the amount of elastic deformation in the other directions may be small.

  At this time, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c are in a predetermined direction (the moving direction of the elastic engagement portion, which is the axial direction in this embodiment) with respect to the bone screw 3 that is the fixing pin. And an engagement force having a component in each of the predetermined direction and the direction orthogonal to the central axis 3x of the bone screw 3. This engaging force is a fixing force for fixing the bone screw 3 as a fixing pin to the intramedullary nail body 1 as an implant body. In the illustrated example, the angular range around the central axis 3x of the portion (contact surface) where the elastic engagement portions 4c, 5c, 6c, 6c, and 7c contact the side portion of the bone screw 3 that is the fixing pin is relatively large. Although narrow, the angle range may be widened to some extent, and the engaging force with respect to the fixing pin may be distributed. For example, by making the contact surface shape of the elastic engagement portions 4c, 5c, 6c, 6c, and 7c into a surface shape (for example, a concave surface shape) along the outer peripheral surface of the above-mentioned angular range of the bone screw 3 that is a fixing pin. The portions that receive the engaging force are dispersed on the outer peripheral surface of the bone screw 3 that is the fixing pin. The angle range is preferably 30 degrees or more, and preferably 60 degrees or more. It may be about 90 degrees. Such an aspect is particularly suitable for a sleeve structure to be described later.

  As an aspect when the elastic engagement portions 4c to 7c are in contact with a position deviated from the central axis 3x of the bone screw 3 to either one side and elastically deform as described above, Not only when the engaging portions 4c to 7c are formed (offset) laterally with respect to the axis 1x, but also the axes 1dx to 1hx of the transverse holes 1d to 1h and the transverse holes 1d to 1h In some cases, the central axis 3x of the bone screw 3 inserted through each is disposed (offset) at a position deviated laterally with respect to the axis 1x. Furthermore, in the positional relationship with respect to the axis 1x, it is only necessary that at least one of the elastic engagement portions 4c to 7c and the bone screw 3 is shifted (offset) laterally with respect to the axis 1x. Here, the elastic engagement portions 4c to 7c and the bone screw 3 may be shifted (offset) to the same side with respect to the axis 1x, and the elastic engagement portions 4c to 7c and the bone screw 3 are on the opposite side. There may be cases where they are shifted (offset). In the present invention, any aspect described above may be used as long as the elastic engagement portions 4c to 7c and the bone screw 3 are disposed at positions relatively offset (offset) to the side of the axis 3x.

  In the case of this embodiment, the elastic engagement portions 4c to 7c are elastically deformed outward in the radial direction of the bone screw 3. Therefore, if necessary, the elastic engagement portions 4c to 7c are elastically engaged with the inner surface facing the lumen 1c of the intramedullary nail body 1. You may provide the groove | channel and recessed part for ensuring the deformation | transformation margin to the side of the parts 4c-7c. Moreover, in this embodiment, the insertion recessed part 5j-8j is provided in a part of insert 2, The deformation | transformation margin to the side of the elastic engagement parts 4c-7c is ensured. On the other hand, in order to ensure the above-described deformation margin, at least a part of the outer surfaces 4ca to 7ca of the elastic engagement portions 4c to 7c on the side where the amount of deformation to the outside is large (as shown in the illustrated example, the tip portion). ) May be provided with a surface (tapered surface) inclined inward in the radial direction toward the larger deformation amount side.

  In the present embodiment, the elastic engagement portions 4c to 7c are provided at sites different from the opening edges themselves that define the individual opening ranges of the opening areas 2d to 2h provided in the insert 2. When the opening edge itself of a certain opening area is configured to act as an elastic engagement portion, the insert 2 (the locking members 4 to 4) is engaged when the elastic engagement portion engages with the fixing pin and is elastically deformed. 8) The basic skeleton is deformed, and it is easy to affect the position and engagement mode of the elastic engagement portion corresponding to another opening region. As a result, the independence of the fixing action of the fixing pin by each elastic engagement portion This is because there is a case where the value decreases. However, as a result, even if the elastic engagement portion is formed on the opening edge itself, for example, a structure in which a slit or a slit is formed along the opening edge, or an extended protrusion along the opening edge is formed. Structures that do not deform the skeleton are also conceivable, and these structures are included in the present invention. In particular, when the elastic engagement portion is configured to protrude from the opening edge (when it is formed to protrude in the shape of a protrusion or a bridge within the opening), the elastic engagement portion is not affected without affecting the basic skeleton. It is possible to configure such that only the joint portion is partially elastically deformed.

  In general, when the elastic engagement portions 4c, 5c, 6c, 6c, and 7c are engaged with the bone screw 3, the operation direction of the insert 2 between the elastic engagement portion and the bone screw 3 (the predetermined direction, That is, in this embodiment, the amount of elastic deformation in the operating direction of the insert 2 of the elastic engagement portion changes according to the relative positional relationship in the direction along the axis 1x) or the bone of the elastic engagement portion. The relative engagement position with respect to the screw 3 changes in the operation direction of the insert 2. For this reason, the elasticity which produces the dispersion | variation in the engagement mode with respect to each bone screw 3 between several (pair) elastic engagement parts 4c, 5c, 6c, 6c, 7c resulting from the dimensional error of each part mutually independently is produced. It can be easily and reliably absorbed by the amount of elastic deformation of the engaging portion and the amount of change in the engaging position. Therefore, the plurality (pairs) of elastic engagement portions 4c, 5c, 6c, 6c, and 7c respectively corresponding to the plurality of opening areas 2d, 2e, 2f, 2g, and 2h are securely engaged with the corresponding bone screws 3, respectively. The bone screw 3 can be fixed with an appropriate fixing force. In the present invention, the engagement is based on the amount of elastic deformation of the elastic engagement portion generated in the operation direction of the locking structure due to the engagement with the fixed pin and the elastic deformation of the elastic engagement portion due to the engagement with the fixed pin. A sufficient effect can be obtained by the presence of at least one of the amount of change in the relative engagement position between the elastic engagement portion and the fixing pin generated in the movement direction of the stop structure.

  In the present embodiment, the interval between the pair of elastic engagement portions 4c, 5c, 6c, 6c, and 7c is set to be slightly smaller than the outer diameter of the shaft portion 3b of the bone screw 3. When this elastic engagement portion comes into contact with the shaft portion 3b, as shown in FIGS. 1D and 1E, the shaft portion 3b becomes a pair of elastic engagement portions 4c, 5c, 6c, 6c, 7c. It is fixed so as to be pushed into the end in the direction of the axis 1x in such a manner that it enters the wedge shape in between and is held by its elastic restoring force. In addition, in the engagement mode between the elastic engagement portion 7c and the bone screw 3 inserted through the opening area 2h, the axis 2hx of the opening area 2h is inclined with respect to the axis 1x. The vicinity of one end in the width direction of the portion 7c engages with the bone screw 3, so that the vicinity of the end elastically deforms outward in the radial direction of the bone screw 3 while twisting the entire elastic engaging portion 7c.

  In the present embodiment, as described above, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c protruding in the direction along the axis 1x abut on the side portion of the shaft portion 3b of the bone screw 3 and are radially outward. The bone screw 3 is fixed while elastically deforming. Therefore, the structural margin (degree of freedom) in the direction along the axis 1x at the engagement portion between the elastic engagement portions 4c, 5c, 6c, 6c, and 7c and the bone screw 3 is increased, which affects the structure accuracy. Without this, the plurality of bone screws 3 can be fixed securely. This makes it possible to make the fixing force of the plurality of bone screws 3 uniform, and to reduce fluctuations in the fixing force when the number of bone screws 3 inserted through the intramedullary nail body 1 increases or decreases. Is also possible.

  Moreover, in this embodiment, since a pair of elastic engaging part 4c, 5c, 6c, 6c, 7c hold | maintains the axial part 3b of the bone screw 3 from the both sides by the elastic restoring force, rotation of the bone screw 3 is carried out. Can be fixed to the intramedullary nail body 1 in a state in which is controlled. Therefore, compared to the case where the fixing pin such as the bone screw 3 is sandwiched between the edge of the transverse hole of the implant body such as the intramedullary nail body 1 and the opening edge of the locking structure such as the insert 2, the fixing pin It is possible to enhance the effect of preventing loosening.

  In addition, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c of the present embodiment protrude separately from the peripheral portion of the insert 2 as described above, and are free ends (end portions 4b, 5b, and 6b). , 6b, 7b), so that the other portion of the insert 2 (the original surrounding portion from which the elastic engagement portion separates) is hardly affected, and locally in the portion engaged with the bone screw 3. It can be securely fixed while elastically deforming. The projecting direction of the elastic engaging portions 4c, 5c, 6c, 6c, and 7c is not particularly limited as long as the structure having the elastic deformation region limited as described above is used. For example, unlike the illustrated example, the elastic engagement portion may have a structure protruding along a plane orthogonal to the axis 1x, or a structure protruding in a direction inclined with respect to the axis 1x. However, as shown in the illustrated example, a structure projecting toward the distal end in the direction along the axis 1x, that is, a structure projecting in the direction of the operation of the insert 2 allows the bone between the intramedullary nail body 1 and the bone. When the screw 3 is fixed, the rigidity necessary for obtaining a predetermined fixing force of the bone screw 3 can be easily ensured. For this purpose, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c can be downsized. Can be achieved.

  In particular, the elastic engagement portions 4c, 5c, 6c, 6c, and 7c have a cross-sectional shape (plate shape) in which the thickness along the radial direction of the shaft portion 3b is smaller than the width along the central axis 3x of the bone screw 3. Since it is configured, it is configured to be easily elastically deformed in a bending manner in the radial direction of the shaft portion 3b while ensuring rigidity in the direction along the axis 1x. In addition, in order to adjust the elastic deformation characteristics in the radial direction of the shaft portion 3b of the elastic engagement portions 4c, 5c, 6c, 6c, and 7c according to the required fixing force of the bone screw 3, along the central axis 3x. Grooves and cuts in the specified direction are formed on the surface (plate surface) of the elastic engagement portion to facilitate elastic deformation, or protrusions (ribs) in a direction perpendicular to the central axis 3x are formed on the elastic engagement portion. It may be formed on the surface (plate surface) to reduce the amount of elastic deformation.

  In the insert 2, the locking members 4 and 5, 5 and 6, 6 and 6, 6 and 7, and 7 and 8 adjacent in the direction of the axis 1 x have the following relationship. That is, when the locking members 4 and 5 are shown as an example, the elastic engagement portion provided in the locking member 4 in a state where the locking members 4 and 5 are in contact (fitted) in the direction along the axis 2x. 4c is accommodated in the accommodation recess 5j provided in the locking member 5 so as to face the opening area 2d provided in the locking member 5 without being restrained by the locking member 5. .

  In addition, in each of the locking members 5, 6, and 7, the opening orientations of the recesses of the housing recesses 5j, 6j, and 7j, or the opening orientations of the opening areas 2d, 2e, 2f, and 2g orthogonal thereto are paired. The orientations of the formation positions of the elastic engagement portions 5c, 6c, and 7c differ by angles θ1, θ2, θ3, and θ4. This is because of a deviation in the transverse direction between the proximal-side transverse hole 1d and the distal-side transverse hole 1e (in the example shown, an angular deviation of 30 degrees clockwise when viewed from the proximal side to the distal side), Deviation in the transverse direction between the transverse hole 1e on the end side and the transverse hole 1f on the distal side (in the example shown, an angular deviation of 60 degrees clockwise when viewed from the proximal side to the distal side), transverse on the proximal side Deviation in transverse orientation between hole 1f and distal transverse hole 1g (in the example shown, an angular deviation of 60 degrees clockwise when viewed from the proximal side to the distal side), proximal transverse hole 1g and distal end This is because the angles correspond respectively to the lateral displacements between the lateral transverse holes 1h (in the example shown, an angular displacement of 30 degrees clockwise when viewed from the proximal side to the distal side).

  Accordingly, the order and type of the locking members 5 to 7 are appropriately selected and replaced, or another locking member having a different angle is manufactured, whereby the transverse holes 1d to 1d of the intramedullary nail body 1 are formed. It is possible to configure the insert 2 that is adapted to various angles of 1h. In the illustrated example, two locking members 6 are used, but it is also possible to use the same locking member in two or more places.

  As an advantage of configuring the insert 2 as an assembly of a plurality of locking members 4 to 8, in addition to the above-described points, the insert 2 can be easily manufactured. In particular, the insert 2 needs to be provided with a plurality of elastic engagement portions 4c to 7c. The elastic engagement portions 4c to 7c in the illustrated example are inserted through the base end portions 4a to 8a and the bone screw 3 for receiving the driving force. It is necessary to provide it separately from the opening areas 2d to 2h, the strut structures 4f to 8f, and the like, and it is provided in a position where it can abut on each bone screw 3 inserted therethrough in a mode of projecting in the axial direction. Since it is necessary, the structure of the insert 2 is greatly complicated. Therefore, in order to facilitate the manufacture of the insert 2 while reducing the size of the insert 2, it is advantageous to form an assembly of the plurality of locking members 4 to 8 as described above. In particular, since the elastic engagement portions 4c to 7c of the locking members 4 to 7 are all formed at the end portions 4b to 7b, the elastic engagement portions 4c to 7c are easily processed, and the processing accuracy is improved. .

  The assembly structure of the plurality of locking members 4 to 8 in the insert 2 is basically arranged by bringing the locking members into contact with each other in the direction of the axis 2x as in the illustrated example, so that the assembly work is complicated. Never become. Further, by adopting a structure in which the elastic engagement portions 4c, 5c, 6c, 6c, and 7c and the receiving recesses 5j, 6j, 6j, 7j, and 8j are fitted, the axis 2x between the respective locking members And the mutual posture (orientation) can be easily determined.

  FIG. 4 is a perspective view showing a state in which the bone fixation system of the present embodiment is applied to the humerus. The intramedullary nail body 1 containing the insert 2 in a released state is inserted from the humeral head 11 which is the proximal end of the humerus 10, and on the proximal side, drilling operations corresponding to the transverse holes 1d to 1h are performed. The bone screws 3-1 to 3-5 are inserted into the transverse holes 1d to 1h and screwed. Similarly, on the distal side, a drilling operation corresponding to the transverse holes 1i and 1j and a screwing operation of the bone screw 13 are performed. On the proximal side, after screwing the bone screws 3-1 to 3-5, the operation portion 9 </ b> C that is also an end cap is further screwed, and the insert 2 is moved in the axial direction to shift to a fixed state. Accordingly, the bone screws 3-1 to 3-5 are fixed to the intramedullary nail body 1.

  FIG. 4 shows a perspective view of a washer (or plate) 15 as a pin engaging member that can be used with the bone screws 3-1 to 3-5. The washer 15 includes a through hole 15a corresponding to an engaged portion for engaging a bone screw. The through-hole 15a has such a size that the shaft 3b of the bone screw 3-1 to 3-5 can be inserted, and its opening edge engages with the head 3a of the bone screw 3-1 to 3-5. Configured to be fixed to the bone screw. Here, it is preferable that the through-hole 15a engaged with the bone screw inserted into the transverse holes 1d to 1h of the intramedullary nail body 1 is formed at the center as shown in the figure. The washer 15 is provided with an auxiliary insertion hole 15b for sewing through which a suture thread is inserted. In the illustrated example, the auxiliary insertion hole 15b is an insertion hole that is sewn to each part such as the rotator cuff (rotator cuff) of the proximal portion of the humerus with a suture, and is near both ends of the through hole 15a. A total of two are formed one by one. The auxiliary insertion hole 15b may be used for inserting another bone screw or pin other than the bone screw 3 inserted into the intramedullary nail body 1. Further, a protrusion (spike) 15c that can be engaged with the surface of the bone is formed on the back surface of the washer 15 (the surface that contacts the bone). In the illustrated example, a pair of protrusions 15c protrude from both side edges near the through hole 15a. The projection 15c serves to hold the bone or bone fragment firmly by the washer 15 engaged with the bone screw 3 fixed to the intramedullary nail body 1 by causing the washer 15 to bite into the bone surface.

  In addition, the bone fixation system of this invention is not limited to the structure as described in the said embodiment, The various different aspect based on the meaning of this invention is included. For example, the implant body is not limited to the intramedullary nail body 1 but may be a bone plate, a CHS plate portion, a sliding screw flange portion, or the like.

  The locking structure is not limited to the insert 2 but includes a sleeve structure fitted to the outside of the intramedullary nail body 1 and a plurality of ring structures (corresponding to the locking members described above). Alternatively, it may be a slide-type locking body that is slidably mounted on the bone plate and restrains the bone screw or the bone pin. The opening area provided in the locking structure does not have to be a hole shape, and may be any as long as it provides a gap configured to allow the fixing pin to be inserted at a position corresponding to the transverse hole provided in the implant body. . Therefore, each opening area may be a notch shape or an oval shape, and each opening area may be constituted by a part of each of an opening and a hole in which a plurality of opening areas are integrated. Further, the transverse hole does not need to have a hole shape surrounded by the entire circumference around the axis, and a part of the transverse hole is opened, particularly when the center axis of the hole is offset with respect to the axis of the implant. A notch-like hole shape may be provided. The present invention has a plurality of elastic engagement portions respectively corresponding to a plurality of transverse holes and opening areas of the implant and fixing pins inserted through them, but does not correspond to any elastic engagement portion in the implant. , Transverse holes and opening areas and fixing pins inserted therethrough (that is, fixing pins not fixed by the elastic engagement portions, or only fixed to the implant body not fixed by other fixing means) It may further have a fixing pin).

  Furthermore, the position setting means is not limited to the position setting means 9 including the elastic portion 9A, the holding portion 9B, and the operation portion 9C, and can move the locking structure in a predetermined direction with respect to the implant body. If it is. For example, it may be constituted by an operating member that is screwed into the female screw 1ca of the intramedullary nail body 1 and is rotatably connected to the insert 2. An operating member that abuts and is screwed into a screw provided in the insert 2 may be used. Furthermore, various position setting means such as a latch mechanism having a leaf spring or the like and a worm-rack engagement structure configured to be able to adjust the position of the locking structure by operating various tools are used. Can do.

  Further, the direction of operation of the locking structure (the predetermined direction) is not limited to the direction toward the distal end in the direction of the axis 1x as described above, but is the direction toward the base end opposite to this. May be. Further, the locking structure may be operated not in the axial direction of the implant (intramedullary nail body 1) but in a direction rotating around the axial line. In these cases, in order to have a function according to the direction of operation of the locking structure, the position setting means is configured to draw the locking structure toward the base end 1a side, or a locking structure. The design can be easily changed to a structure that rotates around the axis 1x.

  Furthermore, the fixing pin is not limited to the bone screw 3 shown in the figure, and any pin can be used as long as it can be inserted into the transverse hole of the implant body. Various types of pins, pegs, nails, spikes, fasteners and the like can be used. Further, as the fixing pin, a pin provided with a shaft body such as a bone screw, a pin, or a peg and a sleeve slidably mounted on the shaft body in the axial direction is used. It may be held and fixed. In this case, if a strong engagement force is applied by the elastic engagement portion to the sleeve, which is structurally subject to thickness restrictions, the sleeve may be deformed to cause a problem in the sliding operation. . However, as in the above-described embodiment, when the elastic engagement portion is engaged with the fixing pin (sleeve), the elastic engagement portion can be elastically deformed in such a manner that the shape along the protruding direction of the elastic engagement portion is bent. If it is configured to move toward a location shifted laterally with respect to the central axis of the fixed pin and engage with the fixed pin (sleeve) at the location, the mutual configuration is as described above. An engagement force having components in two orthogonal directions can be generated. For this reason, the shape of the contact surface that contacts over a predetermined angular range (for example, preferably 30 degrees or more, more preferably 60 degrees or more) around the central axis of the outer peripheral surface of the fixing pin (sleeve) (described above) Preferably, the shape of the contact surface along the outer peripheral surface). As a result, the fixing force can be applied by being distributed over a predetermined angle range of the outer peripheral surface of the fixing pin, so that the fixing force can be ensured and at the same time, deformation of the sleeve can be suppressed and the above problem can be avoided. This is particularly suitable when the engagement range along the central axis of the elastic engagement portion with respect to the fixed pin is limited.

  Further, the pin engaging member of the present invention used by being engaged with the fixed pin has only the through hole 15a, only the through hole 15a and the auxiliary insertion hole 15b, only the through hole 15a and the projection 15c. It may be one having various planar shapes such as a circular shape, a rectangular shape, and a square shape. Further, the pin engaging member is not limited to a plate-like member (plate) such as the washer 15, but holds and fixes bones and bone fragments while being engaged with the bone screw 3 fixed to the intramedullary nail body 1. Any shape can be used as long as it can be used. This pin engaging member expands the range of the bone or bone fragment fixed by the bone screw 3 of the bone fixing system, or increases its fixing force. For example, it is possible to prevent the bone screw 3 from being buried in the bone of the head 3a due to osteoporosis or the like. In particular, in a multi-bone fracture where the large nodule of the proximal portion of the humerus is crushed, if the axial force generated by the insertion of the bone screw 3 between the bone fragments is excessively applied, the reduction position is lost. If a sufficient axial force is not applied to the bone screw 3 for fear, the engaged state of the bone screw 3 with respect to the bone or bone fragment may be relaxed, leading to bone union failure. In the bone fixation system of the present invention, since the bone screw 3 is fixed to the intramedullary nail body 1, a large axial force (compression force) continues to be stably applied between bones and bone fragments via the pin engaging member. Therefore, bone union failure can be prevented more reliably than before.

  In addition, you may use the fixing pin of the structure which comprised the said pin engaging member integrally with the fixing pin, and was provided with the pin engaging part which hold | maintains a bone or a bone fragment integrally. As such a fixing pin, for example, in the case of the bone screw 3 described above, there is a pin configured to have a head portion 3a projecting around. Here, the integrated shape of the head 3a can be a curved shape that wraps around the application region of bone or bone fragments, as in the case of a pin engaging member separate from the fixing pin. Further, the pin engaging member is configured as a locking plate by using the through hole 15a as the engaged portion as a hole with an internal thread, and the fixing pin is formed on the head with the internal screw of the through hole 15a. You may comprise as a locking pin which formed the external thread screwed in a mountain. For example, a male screw that can be screwed into the internal thread of the through hole 15a is formed on the outer periphery of the head 3a of the bone screw 3, and the bone screw 3 is configured as a locking screw for the pin engaging member. To be fixed at a predetermined angle with respect to. Thereby, the direction which a pin engaging member hold | maintains a bone or a bone fragment with respect to arrangement | positioning of an implant main body and a fixing pin can be fixed to a predetermined angle.

  The pin engaging member may include a plurality of through holes 15a with which a plurality of fixing pins inserted through the implant body are engaged. In this case, the pin engaging member may be configured integrally with a certain fixed pin (head thereof) and may be provided with a through hole 15a that engages with another fixed pin. Further, each of the plurality of through holes 15a may be a through hole provided with an internal thread, and any of the through holes 15a is not provided with an internal thread (in this case, the engagement mode with respect to the fixed pin is a predetermined angle). It may change as long as it is within the range. Furthermore, some through holes 15a may be through holes provided with internal threads, and other through holes 15a may be through holes not provided with internal threads. The plurality of fixing pins may also have a head that can be screwed into the internal screw thread, and can be freely angled within a predetermined angle range without being screwed into the internal screw thread. It may have a compatible head. Of course, in each of these cases, the auxiliary insertion hole may be further provided for another fixing pin that is not inserted into the implant body. At this time, the auxiliary insertion hole may have the same form as the above-described through-hole 15a. For example, the auxiliary insertion hole may have an internal thread or may not have an internal thread.

  When the pin engaging member that is integral with or separate from the fixing pin is applied to a plurality of fixing pins that are respectively fixed by the elastic engaging portions in the present invention, a sufficient fixing force to the implant body is provided. Due to the synergistic effect with a plurality of fixing pins fixed in the step, the bone or bone fragment can be held and fixed strongly and reliably. However, the pin engaging member that is integral with or separate from the fixing pin is not limited to the configuration of the present invention, and is inserted into the implant as another invention that is particularly effective when dealing with complicated fracture modes and osteoporosis. In order to solve the problem of enhancing the fixing function of bones or bone fragments by one or more fixing pins as compared with the prior art, essentially any implant (typically, one or more fixing pins inserted) Intramedullary fixation system) can also be applied. At this time, a part or all of the fixing pin inserted into an arbitrary implant may be a fixing pin that is not fixed by the elastic engagement portion, and is not fixed by other means but is simply inserted. There may be only a fixed pin.

DESCRIPTION OF SYMBOLS 1 ... Intramedullary nail main body (implant main body), 1a ... Base end part, 1b ... Terminal part, 1c ... Lumen, 1d-1j ... Cross hole, 1cd ... Inner step part, 2 ... Insert, 2d, 2e, 2f, 2g, 2h ... opening area, 3 ... bone screw (fixing pin), 3x ... central axis, 3a ... head, 3b ... shaft, 3c ... tip, 4, 5, 6, 7, 8 ... locking member, 4a, 5a, 6a, 7a, 8a ... Base end portion, 5b, 6b, 7b, 8b ... End portion, 4c, 5c, 6c, 7c ... Elastic engagement portion, 4d, 5d, 6d, 7d, 8d ... Shaft hole 4e, 5e, 6e, 7e, 8e ... load transmitting portion, 4f, 5f, 6f, 7f, 8f ... strut structure portion, 4g ... held portion, 8k ... vertical groove, 8p ... locking pin, 8g ... supported Part, 5j, 6j, 7j, 8j ... receiving recess, 9 ... position setting means, 9A ... elastic part (coil spring), 9B ... holding part (retaining ring), C ... operating portion (end cap), 3-1 to 3-5 ... bone screw 13 ... bone screw 15 ... washer (pin engaging member), 15a ... through holes

Claims (16)

A bone fixation system applied to bone for bone treatment,
An implant body with a plurality of axially arranged transverse holes;
A fixing pin configured to be inserted into the transverse hole of the implant body;
A plurality of opening areas configured to be operably mounted in a predetermined direction with respect to the implant body and configured to allow the fixing pins to be inserted at positions corresponding to the plurality of transverse holes, and the plurality of openings; Corresponding to each of the areas, provided so as to be engageable in the predetermined direction with respect to the fixing pin inserted through the opening area, and having the predetermined direction with respect to the fixing pin inserted through the opening area A locking structure having an elastic engagement portion provided so as to be elastically deformable by an engagement operation;
Position setting means for operating the locking structure in the predetermined direction with respect to the implant body, and setting an operating position of the locking structure;
A bone fixation system comprising:   The bone anchoring system according to claim 1, wherein the elastic engagement portion protrudes separately from a peripheral portion of the locking structure and includes a distal end portion that is a free end.   The bone anchoring system according to claim 2, wherein the elastic engagement portion protrudes in the predetermined direction, and the distal end portion engages with the fixing pin.   The said elastic engagement part is comprised so that elastic deformation can be carried out in the aspect in which the shape along the protrusion direction of the said elastic engagement part bends, when engaging with the said fixed pin. 4. The bone fixation system according to 3.   The elastic engagement portion is directed toward a position shifted to at least one from the central axis of the fixing pin inserted through the transverse hole and the opening area in accordance with the operation of the locking structure by the position setting means. The bone fixation system according to any one of claims 1 to 4, wherein the bone fixation system is provided to move and engage with the fixation pin at the location.   It has a pair of said elastic engagement part which moves toward the location which shifted to both sides from the central axis of the said fixed pin inserted in the said crossing hole and the said opening area, respectively, and engages with the said fixed pin in the said location, respectively The bone fixation system according to claim 5.   The elastic engagement portion has a cross-sectional shape in which a thickness along a radial direction of the fixing pin is thinner than a width along a central axis of the fixing pin inserted through the transverse hole and the opening region. The bone fixation system according to claim 5 or 6.   The said locking structure is comprised by arranging in the state which the some locking member contact | abutted mutually in the said axial direction, The structure as described in any one of Claims 1-7 characterized by the above-mentioned. Bone fixation system.   The plurality of locking members include a first locking member including the first elastic engagement portion corresponding to the first opening area, and a second different from the first opening area. The bone fixation system according to claim 8, further comprising: a second locking member provided with the second elastic engagement portion corresponding to an opening area.   The first locking member including the elastic engagement portion and the second locking member including the opening region corresponding to the elastic engagement portion of the first locking member are mutually connected. When the first locking member and the second locking member are adjacent to each other in the axial direction, the elastic engagement portion is not restrained by the second locking member. The bone fixation system according to claim 8, wherein the bone fixation system is arranged so as to face the opening area in a state where it can be elastically deformed.   The second locking member accommodates at least a part of the elastic engagement portion of the first locking member, and the elastic engagement portion is not restrained by the second locking member. The bone fixing system according to claim 10, further comprising an accommodation recess configured to be elastically deformable.   The second locking member includes the second elastic engagement portion, and is adjacent to the second locking member on the opposite side of the first locking member in the axial direction. The third locking member has a second opening area corresponding to the second elastic engagement portion, and the second locking member and the third locking member have a locking member. When contacting in the axial direction, the second elastic engagement portion is arranged so as to face the second opening area in a state where it can be elastically deformed without being constrained by the third locking member. The bone fixation system according to claim 10, characterized in that   The said locking member has a support | pillar structure part which transmits the driving force of the said position setting means to the said axial direction without interposing the said elastic engagement part, The any one of Claims 8-12 characterized by the above-mentioned. The bone fixation system as described in.   An engaging portion that engages with the fixing pin; and a pin engaging member that holds the bone or bone fragment interposed between the fixing pin fixed to the implant body and the bone or bone fragment. The bone fixation system according to any one of claims 1 to 13, wherein   15. The bone fixation system according to claim 14, wherein the pin engaging member has a curved shape that wraps around the bone or bone fragment.   The implant body is an intramedullary nail body that is inserted into the medullary bone of the long bone, and the locking structure is an insert that is received in a lumen provided in the intramedullary nail body. The bone fixation system according to any one of claims 1 to 15.

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