JP2018061604A - Bone fixation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bone fixation system that has high correspondence performance with a variety of modes of the bone quality and bone fractures without increasing load on surgery in a bone fixation system for internal fixation using at least a shaft-like bone fixation member.SOLUTION: A bone fixation system is applied to the bone for bone treatment and includes stretchable bone fixation members 10, 20 having: first shaft-like bodies 10A, 20A which are arranged on a distal end side in the direction of axis lines 10x, 20x and have first bone engagement structures 12a, 22b; and second shaft-like bodies 10B, 20B which are arranged on a base end side in the direction of the axis line and configure a slidable stretchable structure in the axial direction between the first shaft-like body and themselves.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bone fixation system, and more particularly to an implant suitable for treating fractures at the epiphysis of long bones.

  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, there is one using an axial bone fixation member such as a bone screw or a hook pin. Also known is a structure that engages with these bone fixation members and uses a plate (bone plate) placed on the surface of the bone to hold the fracture at the epiphysis and guide bone fusion. (For example, refer to Patent Document 1 below). As such a bone fixation system, a desired reduction state of the fracture portion is maintained by using a fixation principle in which two axial bone fixation members are supported by the cortical portion of the bone at three locations. Is known (for example, see Non-Patent Document 1 below).

  The bone fixation member of the bone fixation system as described above can be used for various epiphyses, and among them, elderly patients suffering from osteoporosis etc. in the fracture of the epiphysis on the proximal side of the femur Since there are many cases, and the burden due to the weight of the patient after surgery is large, it is necessary to respond flexibly and reliably according to the bone quality and fracture mode, and it is necessary to maintain the reduction state appropriately according to various situations . In particular, the femoral neck fracture is an inner fracture with a fracture line in the joint, unlike the outer fracture, which is the trochanter fracture outside the joint, and synovial fluid flows between the fractures, Bone fusion is hindered due to the fact that the fracture line is likely to have a steep angle close to vertical, causing shear force to cause separation, and blood flow to the bone head is likely to be blocked, leading to ischemia. Easy to be. In addition, if osteonecrosis of the head is caused by ischemia, replacement surgery for the artificial hip joint must be performed.

US Patent Publication No. 2007/0055248

C. A. Bout, D. M. Cannegieter and J. W. Juttmann "Percutaneous cannulated screw fixation of femoral neck fractures: the three point principle" Injury Vol. 28, No. 2, pp. 135-139,1997

  Although artificial joint replacement may be performed in the difficult situation as described above, this operation places a heavy burden on the patient and is preferably avoided. Further, CHS and intramedullary nails also require a certain surgical burden because the incision range becomes large. On the other hand, in order to reduce the surgical burden, a minimally invasive hook pin is often used. However, even when two or three hook pins are introduced in order to avoid the rotation of the bone head, there are cases where the load cannot be endured, for example, an X-type rotation shift may be caused by the load. In particular, in recent years, the number of elderly people has increased, and in conventional bone fixation systems, the reduction state cannot be maintained due to osteoporosis, or necrosis due to blood flow disorder often occurs in the affected area. If these occur, it will eventually be necessary to perform artificial joint replacement.

  Further, the conventional bone fixing members such as the bone screw and the hook pin may not be able to cope with the growth mode of the bone in the growth period. For example, although a single bone fixation member is used in childhood spondylolisthesis, the head provided at the proximal end of the bone fixation member in advance protrudes larger than the bone surface in order to cope with the neck that becomes larger as a result of growth. And the head of the bone anchoring member must remain on the bone surface even if bone growth occurs. For this reason, since the head of the bone anchoring member is protruded larger than the bone surface immediately after the operation, there is a risk of giving pain to the patient. There is a possibility that problems such as detachment and destruction of bone tissue may occur, and there is a problem that re-operation is necessary. In addition, the protrusion from the bone surface of the base end of the bone fixing member is the bone fixing when the bone engaging portion is detached when the shaft portion of the bone fixing member is slidable with respect to the outer side. It is also caused by the falling of the member.

  Therefore, the present invention solves the above-described problems, and the problem is that in a bone fixation system for performing internal fixation using a bone fixation member, various bone qualities and fracture modes can be obtained without increasing the surgical burden. An object of the present invention is to provide a bone fixation system having a high response force.

  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 is disposed on the distal end side in the axial direction, and is disposed on the first axial body including the first bone engaging structure, on the proximal end side in the axial direction, and on the first side. And a second shaft-shaped body that constitutes a stretchable structure that is slidable in the axial direction with the shaft-shaped body.

  In one aspect according to the present invention, it is preferable to include at least two extendable bone fixing members. In this case, the proximal end of the second shaft-like body of the first extendable bone fixing member includes the first extendable bone fixing member and the second extendable bone fixing member. It is preferable that the base part of the second shaft-like body of the second stretchable bone fixing member can be connected to each other in a detachable manner. For example, both the first extendable bone fixing member and the second extendable bone fixing member can be attached to and detached from each other on the surface of the bone introduced from the first shaft-like body side. It is configured to be connectable in a manner. Here, the first stretchable bone fixation member and the second stretchable bone fixation member are connected in a manner in which the angle between the axes is fixed in a predetermined mutual posture relationship. It is preferred that In particular, it is desirable that the axes are connected so that the axes extend in parallel with each other.

  In the present invention, the second shaft-like body of at least one of the first and second extendable bone fixing members has a second bone at a position adjacent to the distal end side with respect to the proximal end portion. It is preferable to have an engagement structure. For example, the second bone engaging structure is configured to engage a subsurface cortex of the bone. In particular, it is desirable that the second bone engaging structure is a male engaging male screw formed around the axis.

  In the present invention, the first telescopic bone fixing member has a plate portion projecting from a proximal end portion to at least one side of the axis, and the plate portion extends in parallel with the axis. It is preferable that the second telescopic bone fixing member has a head that can be engaged with the opening at the base end of the second shaft-like body. At this time, the opening is preferably a locking screw hole having an internal thread, and the head is a locking male screw that is screwed with the internal thread. Moreover, it is desirable that the second extendable bone fixing member has a second bone engaging structure at a position adjacent to the distal end side with respect to the head of the second shaft-like body. For example, in this second bone engaging structure, both the first and second extendable bone fixing members are introduced into the bone from the side of the first shaft-like body, and the plate is placed on the surface of the bone. When the opening of the part and the head are engaged, it is configured to be able to engage with the cortex below the surface of the bone. Here, it is preferable that the second bone engaging structure is a male screw for engaging bone formed around the second axis. More preferably, the bone engaging male screw has a screw structure having the same lead as the locking male screw.

  In another aspect according to the present invention, in the case of including the extendable bone fixing member, the second shaft-like body has a plate portion projecting from a base end portion to at least one side of the axis, The plate part preferably includes an opening having a second axis extending in parallel with the axis. At this time, the head provided at the base end engages with the opening of the plate portion, so that it can be connected to the extendable bone fixing member in a posture extending along the second axis. It is preferable that the other bone fixing member comprised in is further included. Other bone fixing members (such as bone screws and hook pins) preferably include a second bone engaging structure at a position adjacent to the distal end side with respect to the head. For example, the second bone engaging structure can engage with the cortex below the surface of the bone when the expandable bone fixing member is introduced into the bone from the first shaft-like body side. Configured. Here, it is preferable that the opening is a screw hole for locking provided with an internal thread, and the head includes a male screw for locking engaged with the internal thread. In addition, the other bone fixing member may not be generally extendable and contractible. However, the other bone fixing member may be the second extendable bone fixing member. Furthermore, it is preferable that the base end portion of the other bone fixing member is configured to be connectable with the plate portion of the second shaft-like body of the extendable bone fixing member. For example, when the extendable bone fixing member is introduced into the bone from the side of the first shaft-like body, on the surface of the bone, another bone fixing member and the plate portion of the extendable bone fixing member Are configured to be mutually connectable. Here, it is desirable that the other bone fixing member includes a second bone engaging structure at a position adjacent to the distal end side with respect to the head. For example, the second bone engaging structure can be engaged with a cortex under the surface of the bone when the extendable bone fixing member is introduced into the bone from the side of the first shaft-like body. Configured as follows. Moreover, it is preferable that this 2nd bone engagement structure is the external thread for bone engagement comprised around the said 2nd axis line.

  According to still another aspect of the present invention, in the case of including the extendable bone fixing member, the second shaft-like body is provided with a head at a proximal end and a distal end with respect to the head. Preferably, the second bone engaging structure is provided at a position adjacent to the side. For example, when the extendable bone fixing member is introduced into the bone from the side of the first shaft-like body and the head is placed on the surface of the bone, the second cortex is applied to the cortex below the surface of the bone. The bone engaging structure is configured to be engageable. Here, the second bone engaging structure is a male screw for engaging bone formed around the axis. In this case, it is preferable to further include a plate disposed on the surface of the bone. It is desirable that the plate includes an opening that can be engaged with the head portion provided at a proximal end of the second shaft-like body. In particular, it is desirable that the opening is a screw hole for locking provided with an internal thread, and the head includes a male screw for locking engaged with the internal thread. Moreover, it is preferable that the said plate has a 2nd opening part provided with the 2nd axis line parallel to the axis line of the said opening part. The axis of the opening and the second axis are preferably parallel. This second opening is preferably engaged with the head of another bone fixation member that is installed in a posture extending along the second axis. Here, the second opening is preferably a locking screw hole having an internal thread, and the head of another bone fixing member is preferably a locking male screw that is screwed into the internal thread. . Further, the other bone fixing member is preferably the extendable bone fixing member.

  In the present invention, it is preferable that the first bone engaging structure is a movable engaging portion configured to be movable in a direction intersecting the axial direction. In this case, the movable engagement portion can be configured by various engagement structures that move in the radial direction around the axis and engage with the intraosseous tissue. In particular, the engagement hook is preferably configured to be able to appear and retract in a direction crossing the axial direction. Although this engagement hook may be single, a plurality of engagement hooks may be provided.

  In the present invention, the extendable bone fixing member is configured such that the first shaft and the second shaft are at least partially slidable in the axial direction with respect to the first shaft. It is preferable that the rod-shaped body and the second shaft-shaped body are configured to be rotatable around the axis. Here, the first shaft body and the second shaft body have the first shaft body and the second shaft body in the entire range in which the first shaft body and the second shaft body can slide in the axial direction. It is further desirable to be configured to be relatively rotatable about the axis.

  In the present invention, the telescopic structure may be configured such that the base end of the first shaft-like body does not protrude toward the base end side with respect to the base end of the second shaft-like body, or the first shaft-like body. It is preferable that the slidable range is limited so that the amount of the base end of the second shaft-like body protruding toward the base end side from the base end of the second shaft-like body is limited. In particular, it is desirable that the slidable range is limited so that the base end of the first shaft-like body does not protrude toward the base end side from the base end of the second shaft-like body.

  In the present invention, the extendable bone fixing member includes the first shaft-like member in a part of a range in which the first shaft-like member and the second shaft-like member are slidable in the axial direction. A body and the second shaft-shaped body are configured to be rotatable around the axis, and the extendable bone fixing member includes the first shaft-shaped body and the second shaft-shaped body. The rotation of the first shaft-like body and the second shaft-like body around the axis is regulated in a portion other than the part of the range slidable in the axial direction. Preferably, it is configured.

  In the present invention, the extendable bone fixing member is configured such that the first shaft-like body and the second shaft-like body can rotate around the axis line, and the extendable bone fixing member. From the state in which the first shaft-shaped body and the second shaft-shaped body can rotate around the axis line, the member is configured such that the first shaft-shaped body and the second shaft-shaped body It is preferable to provide a rotation restricting means capable of shifting to a state where the rotation around the axis is restricted.

  In the present invention, of the bottom surface of the plate portion, a first surface portion around a position where the axis of the extendable bone fixing member passes, and a position where the second axis of the opening passes. At least one of the second surface portions around the surface is configured such that a difference in surface shape occurs in a width direction intersecting at least a direction connecting the first axis and the second axis. It is preferred that For example, at least one of the first surface portion and the second surface portion is provided with a shape processing portion in such a manner that a difference in the surface shape in the width direction occurs on at least one side in the width direction. Is desirable.

  According to the present invention, it is possible to provide an excellent effect that it is possible to provide a bone fixation system that has a high ability to cope with bone quality and fracture mode without increasing a surgical burden.

It is explanatory drawing which shows an example of the aspect which applied the expandable bone fixing member of embodiment of the bone fixing system which concerns on this invention to the femur proximal part. It is a longitudinal cross-sectional view which shows the cross section of the 1st expandable bone fixing member of the embodiment with the connection attitude | position of the 2nd expandable bone fixing member, and the expansion perspective view of a plate part. It is a longitudinal cross-sectional view which shows the cross section of the 2nd elastic | stretchable bone fixing member of the embodiment with the enlarged view of the end face and base end vicinity when it sees from a base end side. When the state in which the first telescopic bone fixing member of the same embodiment is applied is viewed from the outer side of the femur, the cross section (dotted line) of the femoral neck and the shape processing portion are not provided. It is a side view shown with the typical cross-sectional shape of the surrounding part of the passage position of the axis line 10x of the plate part in FIG. It is explanatory drawing which shows the other example of the aspect which applied the same embodiment to the femur proximal part.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Initially, with reference to FIG. 2, the structure of the 1st expansion-contraction bone fixing member 10 contained in the bone fixing system of embodiment which concerns on this invention is demonstrated.

[First Stretchable Bone Fixing Member 10] The bone fixing member 10 is not particularly limited, but as shown in FIG. In the example of illustration, it forms in the linear form extended along the axis line 10x. The bone fixing member 10 has a first shaft-like body 10A and a second shaft-like body 10B. The first shaft-like body 10A and the second shaft-like body 10B constitute a telescopic structure that is slidable in the direction of the axis 10x, in the illustrated example, a telescopic structure, and as a result, the bone fixing member 10 Is configured to be extendable and contractible in the direction of the axis 10x. Further, the first shaft-like body 10A is not particularly limited, but has a smooth outer surface that reduces resistance at the time of introduction and hardly affects the reduction state of the fracture portion, and is a protrusion such as a screw. It is desirable to have an outer shape without a structure.

  The first shaft-shaped body 10 </ b> A is disposed on the distal end side of the bone fixing member 10, and the second shaft-shaped body 10 </ b> B is disposed on the proximal end side of the bone fixing member 10. The first shaft-like body 10A has a cylindrical sleeve 11 whose tip is closed, and a pin 12 accommodated therein. A side opening 11a is formed in the side surface of the distal end portion of the sleeve 11, and a curved engagement hook portion 12a at the distal end of the pin 12 can be projected and retracted from the side opening 11a. When the pin 12 is pushed out to the distal end side, the engagement hook portion 12a abuts on the inclined guide surface 11b formed adjacent to the inside of the side opening 11a of the sleeve 11 and the side of the side opening 11a. Pushed out. Thereby, the engagement hook part 12a protrudes toward the outer side of the side part opening 11a which is a direction which cross | intersects the axis line 10x. A plurality of the side openings 11a and the engaging hook portions 12a may be provided so as to be able to appear and disappear at the same position or different positions in the direction along the axis 10x.

  A proximal end opening 11 c is formed at the proximal end of the sleeve 11, and this proximal end opening 11 c enables operation on the proximal end portion 12 b of the pin 12. An internal thread portion 11d is formed inside the proximal end opening 11c, and is configured to be able to be screwed into an external thread portion at the distal end of the inner shaft of an introduction tool (not shown) inserted from the proximal end opening 11c. The base end opening 11c is provided with a tool engaging portion 11e formed of a notch or the like, and comes into contact with the distal end of the outer shaft of the introduction tool and is fitted to each other. The introduction tool is fixed to the sleeve 11 in both the axial direction and the rotational direction by holding the fitting state in the axial direction between the tool engaging portion 11e and the outer shaft by the inner shaft. The For example, the introduction tool is brought into a connected state by the proximal end portion of the outer shaft being tightened in the axial direction with respect to the sleeve 11 by the proximal end portion of the inner shaft.

  The base end portion 12b of the pin 12 is configured to protrude further to the base end side from the base end opening 11c of the sleeve 11 in a state where the engaging hook portion 12a is stored in the side opening 11a as shown in the drawing. Is done. A male threaded portion 12c is formed in a portion adjacent to the base end portion 12b of the pin 12 so as to be connected to a distal end screw hole of an unillustrated extraction tool used at the time of extraction. Although not shown, when the engagement hook portion 12a sufficiently protrudes from the side opening 11a, the position of the base end portion 12b in the axial direction substantially coincides with the base end opening 11c. Thereby, when the engagement hook part 12a is engaged with the bone, there is no protrusion amount of the base end part 12b from the base end opening 11c, or even if it exists, there is no medical problem. Configured to fit within range. The engagement hook portion 12a is a first bone engagement structure that engages with a bone (in the example described later, a bone head Z on the back side of the fracture line) from the inside of the bone, and intersects the axis 10x. This corresponds to a movable engagement portion configured to be movable in the direction of movement.

  The second shaft-like body 10B has a cylindrical barrel portion 13 and a plate portion 14 formed so as to protrude from the base end portion of the barrel portion 13 to one side of the axis 10x. The barrel portion 13 accommodates the proximal end portion of the sleeve 11 of the first shaft-like body 10A so that the sleeve 11 can be slid along the axis 10x. The first shaft-shaped body 10 </ b> A extends from the tip opening 13 a of the barrel portion 13 to the tip side. Further, a proximal end opening 13b is provided at the proximal end of the barrel portion 13, and various operations using the introduction tool, the removal tool, and the like on the proximal end portion of the sleeve 11 and the pin 12 can be performed through the proximal end opening 13b. It is possible. Note that one or a plurality of axial marks 11g configured by ring-shaped grooves or the like may be appropriately formed on the outer peripheral surface of the sleeve 11. In the illustrated example, the marks 11g are formed at a plurality of locations in the axial direction. This mark 11g shows the expansion / contraction state of the first extendable / retractable bone fixing member 10 in an aspect (an aspect in which it can be visually confirmed by a radiographic image such as an X-ray image). If the position of the third mark 11g coincides with the edge of the tip opening 13a of the barrel portion 13 as in the illustrated example, it can be known that the bone fixing member 10 is in the extended state, and the first one If the mark 11g coincides with the distal end opening 13a, it can be known that the bone fixing member 10 is in a shortened state.

  In the illustrated example, the sliding range L of the telescopic structure is limited by the relationship between the shape of the outer peripheral surface of the sleeve 11 and the shape of the inner peripheral surface of the barrel portion 13. The sliding range L is such that the proximal end opening 11c of the sleeve 11 is located on the barrel portion 13 at a position where the first axial body 10A slides toward the proximal end and is most drawn into the second axial body 10B. It is comprised so that it may correspond with the base end opening 13b. However, in practice it is not necessary to match exactly. Thereby, when the engagement hook portion 12a protrudes into the bone, the proximal end portion 12b of the pin 12 and the proximal end opening 11c of the sleeve 11 do not protrude from the proximal end opening 13b of the barrel portion 13, or medical It falls within the range of the protruding amount to the extent that there is no problem. In the case of the illustrated example, neither the proximal end portion 12 b of the pin 12 nor the proximal end opening 11 c of the sleeve 11 protrudes from the proximal end opening 13 b of the barrel portion 13. Thus, since the slidable range is limited to the pull-in side, even if the first shaft-like body 10A is most drawn into the second shaft-like body 10B, the first shaft The base end of the body 10 </ b> A does not protrude from the base end opening 13 b of the barrel portion 13, or is suppressed to a protrusion amount in a range where no medical problem occurs.

  In addition, by attaching the retaining ring 11f to the outer periphery of the sleeve 11, the range in which the first shaft-like body 10A can be slid to the side where it is pulled out from the second shaft-like body 10B is limited. Accordingly, the first shaft-like body 10A is configured so as not to be separated from the second shaft-like body 10B (extraction to the tip end in the axial direction).

  In the present embodiment, the first shaft-shaped body 10A and the second shaft-shaped body 10B are configured to be slidable with respect to each other over the entire slide range L. The two shaft-like bodies 10B are rotatably connected around the axis 10x. However, in a part of the slide range L that can be expanded and contracted as described above, the first shaft-like body 10A and the second shaft-like body 10B can rotate around the axis 10x, but other portions The first shaft-like body 10A and the second shaft-like body 10B may be configured so as not to rotate around the axis 10x. At this time, it is preferable that the part is a position where the operator can easily position the technique during surgery. For example, the two shafts can rotate relative to each other only when the telescopic structure is in the extended state, and cannot be rotated in the intermediate state and the shortened state that are slightly shortened. Furthermore, it is possible to make the rotation impossible in the extended state and the intermediate state, and to rotate in the shortened state. This makes it possible to set the first shaft-like body 10A and the second shaft-like body 10B to an arbitrary relative angular relationship around the axis 10x. That is, it becomes possible to set the first shaft-like body 10 </ b> A to an arbitrary angular relationship with respect to the angular posture of the plate portion 14.

  As described above, the first shaft-like body 10A and the second shaft-like body 10B are configured to be rotatable with respect to each other in a part of the slide range L, and rotate with respect to each other in a part other than the part. When configured to be regulated, a further effect can be obtained by the rotation regulation. For example, in the shortened state in which the first shaft-shaped body 10A is most drawn into the second shaft-shaped body 10B, the first shaft-shaped body 10A and the second shaft-shaped body 10B are mutually connected as in the illustrated example. The first shaft-like body 10A is slightly pulled out of the second shaft-like body 10B from the shortened state, that is, in the extended state and the intermediate state, the first The rotation around the mutual axis of the shaft-like body 10A and the second shaft-like body 10B may be restricted.

  The structure for restricting the rotation includes an outer peripheral surface on the proximal end side of the first shaft-shaped body 10A (an outer peripheral surface on the proximal end side of the sleeve 11) and an inner surface on the proximal end side of the second shaft-shaped body 10B. A part of the slide range L has a cross-sectional shape that can be engaged with each other such that the peripheral surface (the inner peripheral surface on the base end side of the barrel portion 13) can be engaged with each other in the rotational direction. It can comprise by fitting mutually and preparing so that it may not fit in another part. With this configuration, when it is desired to change the relative rotational posture between the first shaft-like body 10A and the second shaft-like body 10B during surgery (for example, the rotational posture of the first bone engaging structure is changed). When adjusting or setting), when it is desired to maintain the rotation posture (for example, the engagement hook portion) in the expansion / contraction state (for example, the shortened state) corresponding to the part of the slide range L After projecting 12a or immediately before it, etc., it may be in a stretched state (for example, the stretched state and the intermediate state) corresponding to other parts other than the above part. As a result, it is possible to adjust or set the rotation posture of the first bone engaging structure, and to obtain the rotation regulating action on the bone (for example, the bone head Z) of the bone fixing member 10 alone. Regardless of the number of members introduced, the holding force (rigidity) against the load in the rotation direction of the bone fixation system can be increased.

  As in the present embodiment, basically, the first shaft-like body 10A and the second shaft-like body 10B are configured to be rotatable around the axis line 10x. The first shaft-like body 10A and the second shaft-like body 10B may be configured to be restricted from rotating around the axis 10x by the restricting means. As this rotation restricting means, for example, an engagement inner surface part having a non-circular cross section formed at the opening edge of the base end opening 11 c of the sleeve 11 and a non-circular cross section formed at the opening edge of the base end opening 13 b of the barrel part 13. And a member that can be inserted into both the engagement inner surface portions and engageable with both engagement inner surface portions around the axis, and is a proximal end portion of the pin 12 It is possible to use a fitting member (not shown) provided with a through-hole through which is inserted. By inserting the fitting member into the base end opening 11c and the base end opening 13b, the first shaft-like body 10A and the second shaft-like body 10B cannot rotate with each other. The rotation restricting means may be a member that restricts rotation at the time of mounting, such as the fitting member, or is always mounted, but when it is in a specific position or posture. A member that restricts rotation may be used.

  The plate portion 14 is a proximal end portion of the bone fixing member 10 that is engaged with the outer surface of the bone, and projects from the proximal end portion of the barrel portion 13 to one side of the axis 10x. The plate portion 14 has an opening portion 14a formed so as to be in parallel with the base end opening 13b. Here, the axis 14x of the opening 14a is set parallel to the axis 10x. The opening 14a is formed in a truncated cone shape having a diameter reduced toward the distal end side (the left side in the figure) along the axis 14x. An internal thread 14b is formed in the opening 14a. The internal thread 14b is configured to be screwable with a male screw 25a formed on the head 25 of the other bone fixing member 20 described later. In the present invention, the axes 10x and 14x are not limited to being parallel, but may be configured such that both axes extend in parallel. Here, “parallel” means to extend along the other, and it is not necessary that the distance between them does not change when viewed in the extending direction, that is, they are not parallel to each other.

  The plate portion 14 is configured integrally with the barrel portion 13. As a result, as described later, it is not necessary to connect (lock and fix) the extendable bone fixing member to a separate plate, so that the amount of work during surgery can be reduced. Moreover, since the plate part 14 protrudes only to one side with respect to the axis line 10x and the opening part 14a is disposed at the tip of the one side, it can be configured compactly. In particular, since the plate portion 14 has a planar shape extending in a direction from the axis 10x toward the one side, the plate portion 14 is configured more compactly. The downsizing of the plate part 14 brings about less invasiveness by reducing the range of incision required at the time of surgery. In the present invention, the plate portion 14 is not limited to a mode of projecting only to one side of the axis 10x, and may be configured to project in a plurality of directions, or within a certain angular range. Alternatively, it may be configured to spread in all directions.

  On the bottom surface (the surface facing the bone surface) 14c provided on the distal end side in the direction of the axis 10x of the plate portion 14, a shape processing portion 14d having a counterbore shape is formed. When the bone fixing member 10 is attached to the bone in the manner shown in FIG. 4 or the like, the shape processing portion 14d is arranged so as to bring the bottom surface 14c closer to the surface shape of the facing portion of the outer portion Y. This is a processed part in which a difference in surface shape is generated on both sides in the width direction when viewed in the width direction obliquely intersecting the line connecting the two. In the case of the illustrated example, the shape processing portion 14d is mainly provided in the surface portion around the passage position (center of the opening portion 14a) of the axis 14x (the periphery of the opening portion 14a) in the bottom surface 14c of the plate portion 14. Yes. However, the shape processing portion 14d is not limited to the illustrated example, and may be formed in an appropriate surface shape over the entire bottom surface 14c. As shown in FIG. 4, in this embodiment, the plate portion 14 is installed on the outer portion Y so that the axis of the plate portion 14 is inclined by an angle φ. For this reason, among the bottom surface 14c of the plate portion 14, the first surface portion around the position where the axis 10x passes and the position around the position where the second axis 14x passes (the center of the opening 14a). In addition to the distance La in the axial direction of the femur, a distance Lw in the width direction orthogonal to the axial direction also exists between the two surface portions (the peripheral edge of the opening 14a). The distance La causes the both surface portions to be placed on the bone surfaces Ba and Bb having different curvatures as shown in FIG. On the other hand, the distance Lw in the width direction causes the surface angles of the bone surfaces Ba and Bb facing the both surface portions to be different from each other.

  In particular, since the angle of the bone surface Ba and the angle of the surface Bb differ in the width direction depending on the latter distance Lw in the width direction, in order to place the bottom surface 14c on the bone surface with good consistency, It is necessary to process the shape according to the change in angle. In the present embodiment, a shape machining portion 14d having a counterbore shape is provided on one side (right side in the drawing) of the second surface portion of the bottom surface 14c. This reduces inconsistencies between the bottom surface 14c and the bone surface caused by the difference in bone surface angle. In the present embodiment, the second surface portion has a shape that is counterbored on one side in the width direction (right side in FIG. 4), but the opposite side in the width direction of the second surface portion (left side in FIG. 4). ) May be thickened, or in the first surface portion, one side in the width direction (right side in FIG. 4) is thickened, or the opposite side in the width direction (left side in FIG. 4) is counterbored. It may be a shape.

  In addition to the above configuration, in order to reduce inconsistency with the bottom surface 14c due to the difference in the surface shape of the bone such as the curvature in the width direction with the distance La, the above-described configuration of the bottom surface 14c is also reduced. The shape of the bottom surface 14c may be configured so that the surface shape of the first surface portion is different from the surface shape of the second surface portion. If it does in this way, the installation property with respect to the outer side part Y of the plate part 14 can further be improved.

  The cross-sectional view of the bottom surface 14c with respect to the bone surfaces Ba and Bb shown in FIG. 4 shows the surface shape of the first surface portion facing the surface Ba and the second surface portion facing the surface Bb. The case where the surface shape is formed to be the same (that is, the case where the shape processing portion 14d is not provided) is shown. In the case shown in the figure, it can be seen that the alignment of the bottom surface 14c with respect to the surface Bb is deteriorated due to the angle change between the surfaces Ba and Bb. Here, the angle θ shown in the figure corresponds to the anteversion angle, which is an angle at which the bone head Z protrudes obliquely forward with respect to the diaphysis of the femur, and the bone fixing member 10 is passed from the outer portion Y to the neck portion X. The inclination angle when the direction of a second axis 10s, which will be described later, when introduced into the bone head Z is inclined forward is shown. Here, each of the instruments 10 and 20 in the illustrated example shown in the present embodiment is for the left femur. In the case of the right femur, the inclination angle θ is set in the opposite direction.

  Next, the second telescopic bone fixing member 20 will be described with reference to FIG.

[Other Bone Fixing Member 20] The bone fixing member 20 is not particularly limited, but as shown in FIG. In the example of illustration, it forms in the linear form extended along the axis line 20x. The bone fixing member 20 has a first shaft-like body 20A and a second shaft-like body 20B. The first shaft body 20A and the second shaft body 20B constitute a telescopic structure, more specifically a telescopic structure, that can slide in the direction of the axis 20x. As a result, the bone fixing member 20 It is configured to be extendable and contractible in the direction of the axis 20x. Further, the first shaft-like body 20A is not particularly limited, but has a smooth outer surface that reduces resistance during introduction and hardly affects the reduction state of the fractured portion, and is a protrusion such as a screw. It is desirable to have an outer shape without a structure.

  The first shaft-shaped body 20 </ b> A is disposed on the distal end side of the bone fixing member 20, and the second shaft-shaped body 20 </ b> B is disposed on the proximal end side of the bone fixing member 20. The first shaft-like body 20A includes a cylindrical sleeve 21 whose tip is closed, and a pin 22 accommodated therein. A side opening 21a is formed on the side surface of the distal end portion of the sleeve 21, and the curved engagement hook portion 22a at the distal end of the pin 22 can be projected and retracted from the side opening 21a. When the pin 22 is pushed out to the distal end side, the engagement hook portion 22a abuts on the inclined guide surface 21b formed adjacent to the inside of the side opening 21a of the sleeve 21 and the side of the side opening 21a. Pushed out. Thereby, the engaging hook part 22a protrudes toward the outer side of the side part opening 21a which is a direction which cross | intersects the axis line 20x. Note that a plurality of the side openings 21a and the engaging hooks 22a may be provided so as to be able to appear and disappear at the same position or different positions in the direction along the axis 20x.

  A proximal end opening 21 c is formed at the proximal end of the sleeve 21, and this proximal end opening 21 c enables operation on the proximal end portion 22 b of the pin 22. An internal thread portion 21d is formed inside the proximal end opening 21c, and is configured to be able to be screwed into an external thread portion at the distal end of the inner shaft of an introduction tool (not shown) inserted from the proximal end opening 21c. The proximal end opening 21c is provided with a tool engaging portion 21e formed of a notch or the like, and abuts on the distal end of the outer shaft of the introduction tool and is fitted to each other. The introduction tool is fixed to the sleeve 21 in both the axial direction and the rotation direction by holding the fitting state in the axial direction between the tool engaging portion 21e and the outer shaft by the inner shaft. The For example, the introduction tool is brought into the connected state by the proximal end portion of the outer shaft being tightened in the axial direction with respect to the sleeve 21 by the proximal end portion of the inner shaft.

  The base end portion 22b of the pin 22 is configured to protrude further from the base end opening 21c of the sleeve 21 to the base end side in a state where the engaging hook portion 22a is stored in the side opening 21a as shown in the illustrated example. Is done. A male threaded portion 22c is formed in a portion adjacent to the base end 22b of the pin 22 to be connected to a distal end screw hole of an extraction shaft (not shown) used at the time of removal. Although not shown, when the engagement hook portion 22a sufficiently protrudes from the side opening 21a, the position of the base end portion 22b in the axial direction substantially coincides with the base end opening 21c. Thereby, when the engagement hook portion 22a is engaged with the bone, there is no protrusion amount of the base end portion 22b from the base end opening 21c, or even if it exists, there is no medical problem. Configured to fit within range. The engagement hook portion 22a is a first bone engagement structure that engages with a bone (in the example described later, a bone head Z on the back side of the fracture line) from the inside of the bone, and intersects the axis 20x. This corresponds to a movable engagement portion configured to be movable in the direction of movement.

  The second shaft body 20 </ b> B has a cylindrical barrel structure 23. In the illustrated example, the second shaft-like body 20 </ b> B is configured only by the barrel structure 23. The barrel structure 23 has a substantially smooth cylindrical outer surface on the tip side, and has a basic shape of a rotating body centered on the axis 20x. On the base end side of the barrel structure 23, a male thread 24 for bone engagement is provided on the cylindrical outer surface. The male screw 24 is located below the surface of the bone (proximal femur in the illustrated example) into which the first and second extendable bone fixing members 10 and 20 are introduced from the first shaft-like bodies 10A and 20A ( In the illustrated example, it is a second bone engaging structure that engages with the cortex immediately below the outer portion Y). The barrel structure 23 accommodates the base end side portion of the sleeve 21 of the first shaft-like body 20A so as to be slidable along the axis 20x. The first shaft-like body 20A extends from the distal end opening 23a of the barrel structure 23 so as to protrude toward the distal end side. Also, a proximal end opening 23b is provided at the proximal end of the barrel structure 23, and various operations using the introduction tool, the removal tool, and the like on the proximal end portion of the sleeve 21 and the pin 22 can be performed through the proximal end opening 23b. It is possible. The mark 21g is the same as the mark 11g.

  In the case of the illustrated example, the first shaft-shaped body 20A and the second shaft-shaped body 20B are slidable with respect to each other due to the relationship between the shape of the outer peripheral surface of the sleeve 21 and the shape of the inner peripheral surface of the barrel structure 23. The configured range is limited to the slide range L. This slide range L is a position where the first shaft-like body 20A slides to the proximal end side and is most drawn into the second shaft-like body 20B (barrel structure 23), and the proximal end opening 21c of the sleeve 21 is reached. Is configured to substantially coincide with the proximal end opening 23 b of the barrel structure 23. However, in practice it is not necessary to match exactly. As a result, when the engagement hook portion 22a protrudes into the bone, the proximal end portion 22b of the pin 22 does not protrude from the proximal end opening 21c or falls within a protrusion amount range that is not medically problematic. . In the case of the illustrated example, neither the base end portion 22 b of the pin 22 nor the base end opening 21 c of the sleeve 21 protrudes from the base end opening 23 b of the barrel structure 23. Thus, since the slidable range is limited to the pull-in side, even if the first shaft-like body 20A is the most retracted state inside the second shaft-like body 20B, the first Part of the shaft-like body 20A does not protrude from the base end opening 23b of the barrel structure 23, or is suppressed to a protruding amount in a range where no medical problem occurs.

  In addition, by attaching the retaining ring 21f to the outer periphery of the sleeve 21, the range in which the first shaft-like body 10A can be slid to the side where it is pulled out from the second shaft-like body 10B is limited. Thus, the first shaft-like body 20A is configured so as not to be separated from the second shaft-like body 20B (extraction to the tip end in the axial direction).

  In the present embodiment, the first shaft-shaped body 20A and the second shaft-shaped body 20B are slidable with respect to each other over the entire slide range L. The two shaft-like bodies 20B are rotatably connected around the axis 20x. However, in a part of the slide range L that can be expanded and contracted as described above, the first shaft-like body 20A and the second shaft-like body 20B can rotate around the axis 20x, but other parts The first shaft-like body 20A and the second shaft-like body 20B may be configured so as not to rotate around the axis 20x. At this time, it is preferable that the part is a position where the operator can easily position the technique during surgery. For example, both shafts can rotate relative to each other only when the telescopic structure is in the extended state, and can be configured so as not to rotate in the slightly shortened intermediate state and the shortened state. In addition, it is possible to make it impossible to rotate in the extended state and the intermediate state, and to rotate in the shortened state. This makes it possible to set the first shaft-like body 10A and the second shaft-like body 10B to an arbitrary relative angular relationship around the axis 10x. That is, the first shaft-like body 20A can be set to an arbitrary angular relationship with respect to the angular orientation of the male screw 24 for bone engagement and the male screw 25a for locking.

  As described above, the first shaft-shaped body 20A and the second shaft-shaped body 20B are configured to be rotatable with respect to each other in a part of the slide range L, and rotate with respect to each other in a part other than the part. When configured to be regulated, a further effect can be obtained by the rotation regulation. For example, in the shortened state in which the first shaft-shaped body 20A is most drawn into the second shaft-shaped body 20B, the first shaft-shaped body 20A and the second shaft-shaped body 20B are mutually connected as in the illustrated example. The first shaft-like body 20A is slightly pulled out of the second shaft-like body 20B from the shortened state, that is, in the extended state and the intermediate state, the first The rotation around the mutual axis of the shaft-like body 20A and the second shaft-like body 20B may be restricted.

  The structure for restricting the rotation includes an outer peripheral surface on the proximal end side of the first shaft-shaped body 20A (an outer peripheral surface on the proximal end side of the sleeve 21) and an inner surface on the proximal end side of the second shaft-shaped body 20B. In a part of the slide range L, the cross-sectional shapes that can be engaged with each other such that the peripheral surfaces (the inner peripheral surface on the base end side of the barrel structure 23) can be engaged with each other in the rotational direction. It can comprise by fitting mutually and preparing so that it may not fit in another part. With this configuration, when it is desired to change the relative rotational posture between the first shaft-like body 20A and the second shaft-like body 20B during the operation (for example, the rotational posture of the first bone engaging structure is changed). When adjusting or setting), when it is desired to maintain the rotation posture (for example, the engagement hook portion) in the expansion / contraction state (for example, the shortened state) corresponding to the part of the slide range L After projecting 22a or immediately before, etc., it may be in an expanded / contracted state (for example, the extended state and the intermediate state) corresponding to other parts other than the above part. As a result, it is possible to adjust or set the rotational posture of the first bone engaging structure, and to obtain the rotation regulating action on the bone (for example, the bone head Z) of the bone fixing member 20 alone. Regardless of the number of members introduced, the holding force (rigidity) against the load in the rotation direction of the bone fixation system can be increased.

  As in the present embodiment, basically, the first shaft-like body 20A and the second shaft-like body 20B are configured to be rotatable around the axis 20x. You may comprise so that rotation of the 1st shaft-shaped body 20A and the 2nd shaft-shaped body 20B may be mutually restrained around the axis line 20x by a control means. As the rotation restricting means, for example, an engagement inner surface portion having a non-circular cross section formed at the opening edge of the base end opening 21c of the sleeve 21, and a non-circular cross section formed at the opening edge of the base end opening 23b of the barrel structure 23. And a member that can be inserted into both the engagement inner surface portions and engageable with both engagement inner surface portions around the axis, and is a proximal end portion of the pin 12 It is possible to use a fitting member (not shown) provided with a through-hole through which is inserted. By inserting this fitting member into the base end opening 21c and the base end opening 23b, the first shaft-like body 20A and the second shaft-like body 20B cannot rotate with each other. The rotation restricting means may be a member that restricts rotation at the time of mounting, such as the fitting member, or is always mounted, but when it is in a specific position or posture. A member that restricts rotation may be used.

  The bone engaging male screw 24 is a thread for engaging with the cortex of the bone (cortex of the outer portion Y in the illustrated example), and a positive tapping blade 24a (3 in the illustrated example) for enabling self-tapping. ) And reverse tapping blades 24b (two in the illustrated example). Here, the positive tapping blade 24a is used for self-tapping when the barrel structure 23 is screwed into the prepared hole of the bone. The reverse tapping blade 24b is for self-tapping when the barrel structure 23 is extracted from the bone when the bone fixing member 20 is extracted. The latter is provided so that the bone fixation member 20 can be extracted by tapping the callus formed in the healing process.

  At the base end of the barrel structure 23, a truncated cone-shaped head portion 25 having a diameter that is increased toward the base end side is formed. Similar to the other parts of the barrel structure 23, the head 25 has a rotating body-like basic shape centered on the axis 20x. A male screw 25 a for locking is formed on the outer periphery of the basic shape of the head 25. The male screw 25a for locking is a double thread in the illustrated example. In the process where the male screw 24 is screwed (tapped) into the cortex below the surface of the bone, the male screw for locking is set so that the male screw 25a is screwed in synchronization with the internal thread 14b of the opening 14a. 25a and the male screw 24 for bone engagement preferably have a screw structure having the same lead S. Inside the head portion 25, a tool engaging portion 25b such as a hexagonal hole structure for engaging with a tool such as a wrench and rotating the second shaft-like body 20B is formed. The male screw 25a is a multi-threaded screw (two-threaded screw in the illustrated example) in order to obtain sufficient axial force even if the thickness around the head portion 25 and the opening portion 14a of the plate portion 14 is reduced.

  It should be noted that the second extendable bone fixing member 20 and the opening 14a of the plate portion 14 include the entire first shaft-like body 20A of the second extendable bone fixing member 20 and the second axial shape. The body 20B is dimensioned so that all parts other than the head 25 (more specifically, the base end of the head 25) can be inserted into the opening 14a. As a result, the first extendable bone fixing member 10 is first introduced into the bone (proximal femur) from the first shaft-like body 10A side, and the plate portion 14 of the second shaft-like body 10B is inserted. After being placed on the surface of the bone (outer portion Y), the second telescopic bone fixing member 20 can be introduced into the bone (proximal femur) through the opening 14a.

  Next, an example of the application mode shown in FIG. 1 using the bone fixing members 10 and 20 of the above embodiment will be described.

[First Application Mode] This mode is an application example to a femoral neck fracture (inner fracture), and the two bone fixing members 10 and 20 are placed outside the femur across the fracture line of the neck X of the femur. It is introduced from the part Y to the inside of the bone head Z. As shown in FIG. 4, the bone fixation member 20 introduced on the distal side is introduced so as to be supported by the inner surface of the cortex on the distal side of the neck X from the outer side Y, and is introduced on the proximal side. The bone fixing member 10 is introduced so as to be supported by the inner surface of the cortex behind the neck X from the outer side Y. As a result, the bone fixing members 10 and 20 are supported by the cortex at three locations, the outer side Y, the distal side of the neck X, and the rear of the neck X.

  In the above aspect, first, the guide pin is inserted along the first reference line 20s for introducing the distal bone fixing member 20, and the pilot hole is drilled with a drilling tool such as a drill or a reamer. The first reference line 20s passes through the inner side of the cortex on the distal side of the neck X and moves toward the inside of the bone head Z. Then, a second reference line 10s passing through the inner side of the cortex behind the neck X is set with reference to the guide pin or the punching tool introduced along the first reference line 20s, and the guide pin is inserted. Drill a pilot hole. The setting position of the second reference line 10s varies depending on the size of the patient's neck X. However, as shown in FIG. 4, the distance between the bone anchoring member 10 and the bone anchoring member 20 of the present embodiment (this is the distance between the axes 10x and 20x, that is, the axis 10x and the axis of the opening 14a of the plate portion 14). Equal to the interval with 14x.) G is constant. Therefore, regardless of the size of the neck X, the angle φ is adjusted so that the bone fixing member 10 is brought into contact with the inner side of the rear cortex when the bone fixing member 10 is inserted along the second reference line 10s. The position of the second reference line 10s is set. That is, when the neck X is large, the angle φ is increased, and when the neck X is small, the angle φ is decreased so that the bone fixing member 10 is in contact with the cortex behind the neck X. Adjust the position.

  The first reference line 20s and the second reference line 10s are basically parallel to each other, but can be set to an appropriate mutual attitude relationship depending on the situation. In order to ensure this mutual posture relationship, a guide device (not shown) is used. This guide device defines the mutual posture relationship between the first reference line and the second reference line respectively corresponding to the two bone fixation members 20, and usually sets both reference lines in parallel. It is a parallel guide device. It is also possible to define the mutual posture relationship using the opening 14a of the plate portion 14. It should be noted that, as shown in the illustrated example, the bone fixing members 10 and 20 need to be introduced in parallel to each other in order to cope with the shortening action (bone head shortening) of the fractured part in the bone fusion process.

  Next, the proximal bone fixing member 10 is introduced along the second reference line 10s by a guide pin or the like introduced along the second reference line 10s. At this time, the bone fixing member 10 is inserted into a guide pin or a drilling tool in which the opening portion 14a of the plate portion 14 is introduced along the first reference line 20s, or various tools connected thereto. Thus, it is introduced along the second reference line 10s. The introduction of the bone fixing member 10 uses the above-described introduction tool that is screwed into the female screw portion 11d of the sleeve 11 and that engages with the tool engagement portion 11e. The introduction tool is fixed to the sleeve 11 both in the axial direction along the second reference line 10s and in the rotational direction around the second reference line 10s. At this time, the insertion depth of the bone fixing member 10, the direction of the opening of the side opening 11a, and the direction of protrusion of the engagement hook part 12a are determined.

  In the bone fixing member 10, the sliding amount of the first shaft body 10 </ b> A and the second shaft body 10 </ b> B can be appropriately set by the introduction tool. When the bone fixing member 10 is in the longest state, that is, in the extended state, the plate portion 14 of the second shaft-like body 10B is pushed by pushing the first shaft-like body 10A into the perforated portion with an introduction tool. It abuts on the outer part Y. In this state, by pushing the proximal end portion 12b of the pin 12 with another pin operation tool, the engagement hook portion 12a can be protruded from the side opening 11a into the bone, and the first shaft-like body 10A is Can be engaged.

  In the present embodiment, since the bone fixing member 10 is configured to be extendable / contractable, the expansion / contraction structure of the first shaft-like body 10A and the second shaft-like body 10B is used in any intermediate state within the slide range L. It is also possible. In this case, the introduction depth of the first shaft-like body 10A is appropriately set by the introduction tool, and the engagement hook portion 12a is projected by the pin operation tool and engaged with the bone. Thereafter, if necessary, the second shaft-like body 10B is pushed in with another instrument and brought into contact with the surface of the outer portion Y. The depth of the engagement position of the engagement hook portion 12a is adjusted by a doctor depending on the relationship between the patient's head position and the size of the bone fixing member 10, the quality of the bone in the patient's bone head Z, and the like. Therefore, the slide structure of the bone fixing member 10 is extremely effective in that the number of preparations for each implant size can be reduced and the size exchanging operation at the time of operation is unnecessary.

  When the installation of the bone fixing member 10 is completed as described above, the bone fixing member 20 is then introduced along the first reference line 20s defined by a guide pin or the like. Also in the bone fixing member 20, an introduction tool that is fixed in the axial direction and the rotational direction at the proximal end of the sleeve 21 is used as described above. When the first shaft-like body 20A is introduced into the perforated portion and the male thread 24 for bone engagement of the second shaft-like body 20B reaches the outer portion Y, the rotary drive tool engaged with the tool engaging portion 25b is used. The second shaft-like body 20B (barrel structure 23) is rotated, and the male screw 24 is screwed into the bone. The male screw 24 is screwed in by tapping around the perforated portion by self-tapping by the positive tapping blade 24a, and thereby the male screw 24 is firmly engaged with the cortex below the surface of the outer portion Y.

  At this time, the head portion 25 is inserted into an opening portion 14a formed in the plate portion 14 of the bone fixing member 10, and a locking male screw 25a is screwed into the internal thread 14b. The second shaft-like body 20B of the bone fixing member 20 is fixed to the plate portion 14 by screwing the internal thread 14b of the opening 14a, which is a screw hole for locking, and the male screw 25a for locking. That is, the second shaft-like body 20B is fixed in the direction of the axis 20x with respect to the plate portion 14 by a locking effect. On the other hand, the second shaft-like body 20B is also engaged with the cortex of the outer portion Y by the male screw 24 for bone engagement. This means that the plate portion 14 (and hence the axis 10x of the bone fixing member 10) is firmly fixed to the outer portion Y via the locking structure. In addition, the effect of the locking structure ensures angular stability with respect to the plate portion 14 or the outer portion Y of the bone fixing member 20. This angular stability enhances the rigidity of the mutual posture (parallelism) between the bone anchoring members 10 and 20, and also cortex near the bone surface of the bone anchoring members 10 and 20 through the male screw 24 for bone engagement. The fixing force with respect to (outer part Y) is increased.

  Finally, after confirming that the first shaft-like body 20A is disposed at an appropriate depth, the engagement hook portion 22a is projected from the side opening 21a by the pin operation tool, and is engaged with the bone. At this time, with the introduction tool fixed to the first shaft-like body 20A, the positional relationship in the axial direction between the first shaft-like body 20A and the second shaft-like body 20B is an appropriate constant relationship ( For example, if the second shaft-like body 20B is screwed in by the rotary drive tool, the first shaft-like body 20A at that time has an appropriate depth in the drilling portion. Therefore, the engagement hook portion 22a can be projected as it is. In order to do this, for example, the introduction tool connected to the base end of the first shaft-like body 20A and the rotary drive tool connected to the base end of the second shaft-like body 20B are coupled to each other. When this is done, the expansion and contraction of the bone fixing member 20 depends on the positional relationship in the axial direction between the connection position of the introduction tool with respect to the first shaft body 20A and the connection position of the rotary drive tool with the second shaft body 20B. What is necessary is just to set it as the structure hold | maintained so that a structure may always be in an expansion | extension state and other fixed expansion-contraction state.

  As described above, the first shaft bodies 10A and 20A having the first bone engaging structure and the second shaft constituting the telescopic structure between the first shaft bodies 10A and 20A. By including the extendable bone anchoring members 10 and 20 having the rod-like bodies 10B and 20B, the proximal end portion of the bone anchoring member 10.20 can be applied to the cortex on the surface of the bone or below the surface (outer portion Y). The position (engagement position) in the axial direction of the first bone engaging structure provided at the distal end side portion of the bone fixing member 10, 20 after firmly fixing the second shaft-like body 10B, 20B to the bone. Can be arbitrarily changed, adjusted and set. As a result, this embodiment is a bone fixation that has a flexible and reliable correspondence that can be applied to fragile bones such as osteoporosis and complex fractures such as the unstable classification of stages III and IV of the Garden classification. System.

  In particular, adaptability to shortening action (bone head shortening) in the bone healing process is ensured by making the engagement position of the first bone engaging structure movable with respect to the second shaft-like bodies 10B and 20B. it can. For this reason, it is necessary to install the second shaft-like bodies 10B and 20B in a slidable state with respect to a bone portion near the surface of the bone (a portion closer to the surface than the fracture line, for example, the outer portion Y). Therefore, the second shaft-like bodies 10B and 20B can be applied to the bone portion in a highly adhesive manner. Therefore, since a plurality of bone anchoring members can be applied so as to be supported together by the cortex under the surface of the bone, the rigidity for maintaining the relative posture between the bone anchoring members 10 and 20 can be greatly improved. Thereby, for example, it is possible to avoid the occurrence of X-type rotational dislocation (chopsticks phenomenon) between the bone fixing members 10 and 20. Such a fixation mode is also advantageous in that the risk of local compression on fragile bone such as osteoporosis can be avoided by improving the rigidity of the entire bone fixation system.

  In the case of this embodiment, specifically, the bone fixing members 10 and 20 are configured such that the first shaft-like bodies 10A and 20A and the second shaft-like bodies 10B and 20B are slidable by an elastic structure. With respect to the second shaft-like bodies 10B, 20B engaged with the outer portion Y by the plate portion 14 and the male screw 24, the first bone-engaging structure (engagement hook portion) of the first shaft-like bodies 10A, 20A. 12a, 22a) can be appropriately set along the first reference line 20s and the second reference line 10s at positions where the bone head Z is engaged (depth in the perforated part).

  In particular, when the first bone engaging structure is provided with movable engaging portions such as the engaging hook portions 12a and 22a, the first shaft-like bodies 10A and 20A and the second shaft-like body 10B. , 20B are connected to each other so as to be rotatable around the axis, so that the movable engaging portions such as the engaging hook portions 12a, 22a protrude into the bone in the direction of the second shaft-like bodies 10B, 20B. It can be arbitrarily set regardless of the rotational attitude around the axis. As described above, the first bone engagement structure for the portion (bone head Z) located on the back side of the fracture line is provided, and the second bone engagement for the portion (outer side portion Y) located on the surface side of the fracture line. In the bone fixation system provided with the joint structure, since the depth and direction of the first bone engagement structure can be arbitrarily set, it is possible to flexibly and reliably cope with the bone quality and the fracture mode.

  Note that the rotatable connection structure around the axis between the first shaft-like bodies 10A and 20A and the second shaft-like bodies 10B and 20B sets the angle φ of the bone fixing member 10 to an appropriate value. On the other hand, when the engagement hook portion 12a is set in an optimal direction, or while properly locking the male screw 25a for locking the head portion 25 of the bone fixing member 20 to the internal thread 14b of the opening portion 14a, In the case where the engagement hook portion 22a is set in the optimum direction, any structure is extremely effective.

  Furthermore, in this embodiment, since a bone fixing member equivalent to a minimally invasive hook pin or bone screw is used in the outer shape, the operation burden can be reduced. In addition, since the first bone engaging structure is also equivalent to the hook pin, it is expected that relatively stable fixation can be obtained even in unstable fractures in situations where X-type rotational dislocation is avoided for the above reasons. it can. In particular, as described above, the connecting portion (the plate portion 14 and the head portion 25) between the second shaft-like bodies 10B and 20B is firmly fixed to the vicinity of the bone surface (outer portion Y). Also, weak points such as generation of pain due to dropping of hook pins and bone screws do not occur in this embodiment. In addition, since the bone fixing members 10 and 20 of the present embodiment are both provided with a telescopic structure, when the bone growth is fast as in the treatment of pediatric spondylolisthesis, the shortened state or the intermediate state at the time of surgery. By doing so, the first shaft-like body expands in a state where the first shaft-like body is engaged with the bone in the bone head as the bone grows, so that it is not necessary to project the proximal end (head) of the bone fixing member from the bone surface. Therefore, pain due to protrusion from the bone surface is not given to the patient, and occurrence of a malfunction and re-operation due to this are unnecessary.

  In the case of this embodiment, specifically, the second shaft-like body 10B of the bone fixing member 10 is connected to the second shaft-like body 20B of the bone fixing member 20 via the plate portion 14, and this second shaft-like body 20B is connected to the second shaft-like body 20B. Since the shaft-like body 10B is engaged with the cortex of the outer portion Y by the male screw 24 and is locked to the plate portion 14 by the male screw 25a, the shaft-like body 10B is pressed between the bone surfaces and between the bone portions on both sides of the fracture line. Even without increasing the compression, the bone fixing members 10 and 20 can be fixed to each other in a predetermined mutual posture, and at the same time, firmly fixed to the vicinity of the bone surface (outer portion Y). In addition, the locking of the plate portion 14 and the male screw 25a essentially eliminates the need to compress the plate portion 14 against the bone surface (the surface of the outer portion Y), thereby preventing complications due to blood circulation inhibition. As described above, the plate 14 is firmly fixed to the vicinity of the bone surface (outer portion Y) indirectly through the second bone engaging structure (the male screw 24 for bone engagement). Can do.

  Furthermore, in this embodiment, by changing the rotation angle posture around the axis 10x of the second shaft-like body 10B, the bone fixing member 20 introduced on the distal side is brought into the proximal side with respect to the first reference line 20s. The orientation of the second reference line 10s of the bone fixing member 10 to be introduced (determined by the angle φ in FIG. 4) can be arbitrarily set. Therefore, by adjusting the orientation according to the size of the femur of the patient, the proximal side of the neck X with respect to the first reference line 20s set at a position inscribed in the cortex on the distal side of the neck X The second reference line 10s can be reliably set at a position inscribed in the cortex behind the head. The interval G between the first reference line 20s and the second reference line 10s can be set using a parallel guide device (not shown) corresponding to the interval G adapted to the bone fixation members 10 and 20. In particular, as shown in the illustrated example, the plate portion 14 protrudes from the base end portion to only one side of the axis 10x (second reference line 10s), and the opening portion 14a is provided at the end portion on the one side, whereby the plate portion Since the exclusive area of 14 can be kept to the minimum necessary for connecting the bone anchoring members 10 and 20, the surgical burden can be further reduced by further minimization. In this case, if the shape of the plate part 14 is a shape extended in the direction connecting the axes 10x and 14x, it is desirable in terms of further miniaturization.

  At this time, the bottom surface 14c of the plate portion 14 is configured to have a surface shape that is more easily adapted to the bone surface of the outer portion Y by the shape processing portion 14d. As described above, the distance in the width direction on the plane orthogonal to the axis of the femur between the position where the axis 10x of the plate portion 14 passes and the position where the axis 14x of the opening 14a of the plate portion 14 passes. Lw exists. Thus, the surface angle facing the bottom surface 14c by the distance Lw between the bone surface Ba facing the first surface portion of the bottom surface 14c and the bone surface Bb facing the second surface portion is as follows. It will be different. Such changes depending on the location of the surface angle of the bone deteriorate the consistency with the bottom surface 14c of the plate portion 14. More specifically, when the surface shape of the bottom surface 14c of the plate portion 14 is formed to match one of the bone surfaces Ba and Bb (Ba in the illustrated example), inconsistency with respect to the other (Bb in the illustrated example). Will increase. Therefore, as described above, in at least one of the first surface portion and the second surface portion, the width direction as viewed in the width direction intersecting with the direction connecting the axis 10x and the second axis 14x. It is possible to improve the above-mentioned consistency by providing a shape processing portion 14d for making a difference in surface shape between the two sides, that is, forming both sides to have a surface shape different from the symmetrical shape. .

  Depending on the bone quality and fracture mode, a third bone fixing member may be required, but the two bone fixing members 10 and 20 are introduced at positions suitable for the affected area size of the patient as described above. Therefore, the third can be introduced to an optimal position, for example, a position inscribed in the front cortex on the proximal side of the neck, without being connected or coupled to the two bone fixing members 10 and 20. . In addition, when using the bone fixing member 20 as a 3rd, another opening part 14a may be formed in the plate part 14, and the head 25 may be rock-fixed similarly to the above.

  Locking and fixing by screwing the internal thread of the opening 14a and the male screw 25a of the head 25 is configured such that the male screw 24 for bone engagement and the male screw 25a for locking are synchronized (the leads are matched). Due to inappropriate separation of the plate portion 14 from the bone surface, incomplete screwing of the locking screws (internal screw thread 14b and male screw 25a), bone thread formed by tapping the male screw 24 for bone engagement Destruction can be prevented. In addition, the above configuration remains at the position relative to the bone surface (surface of the outer portion Y) of the plate portion 14 at this time when the second shaft-like body 20B of the second extendable bone fixing member 20 is screwed. This means that the plate portion 14 is locked and fixed. Therefore, the position of the plate portion 14 after the completion of screwing can be set at the time of screwing work. In addition, when the male screw 25a is a multi-threaded screw as in the illustrated example, the axial force of the screw can be secured and reliable locking can be realized while limiting the thickness of the plate portion 14 and the head 25. The above points are not limited to those for the plate portion 14, and the same applies to an independent plate such as a plate 15 described later.

  The bone fixing member 10 of the present embodiment fixes the bone fixing member 20 connected to the opening portion 14a of the plate portion 14 in a posture having an axis 20x parallel to the axis 10x and at a short interval G. For this reason, unlike the CHS type bone fixation system, it is not necessary to fix the plate portion with a transverse screw, and the area of the plate portion is small, and the incision range for screwing the transverse screw is also large. Since it becomes unnecessary, it can maintain minimal invasiveness.

  Next, an example of an application mode different from the above will be described with reference to FIG.

[Second Application Mode] In this mode, a fracture portion similar to the above is fixed by using two bone fixing members 20. The method for introducing each bone fixing member 20 can be performed in the same manner as the method for introducing the bone fixing member 20 in the first application mode. The introduction procedure between the two bone fixation members 20 and 20 can be performed in the same manner as the procedure between the bone fixation members 10 and 20 in the first application mode.

  In this application mode, the individual bone fixation members 20 are attached to the proximal portion of the femur without being connected to each other. At this time, the first shaft-like body 20A of each bone fixing member 20 is engaged with the inside of the bone head Z by the engaging hook portion 22a from which each protrudes, and each of the second shaft-like bodies 20B has the first The external thread Y is engaged with the cortex of the outer portion Y by the male screw 24 which is the second bone engaging structure. Accordingly, in this case as well, as in the first application mode, the two bone anchoring members 20 and 20 have the cortex on the distal side of the neck X, the cortex on the proximal side, and the cortex on the outer side Y. It will be in the state supported in total three places. In this case as well, the third bone fixing member 20 may be further introduced as in the first application mode.

  The two or three bone fixing members 20 shown in FIG. 5 may be indirectly connected or connected to each other by a separately prepared plate 15 (broken line in the drawing). The plate 15 preferably includes a number of openings 15a corresponding to the number of the bone fixing members 20 or more. Specifically, the number of openings 15a is preferably a plurality, and is two in the illustrated example, but may be three or more. At least one of the openings 15a is preferably a screw hole for locking provided with an internal thread 15b on the inner surface of the frustoconical opening, like the opening 14a. In this case, the head 25 of the bone fixing member 20 is provided with a locking male screw 25a on the outer peripheral surface of the truncated cone, and this male screw 25a is screwed into the internal thread 15b of the opening 15a. When there are two openings 15a as in the illustrated example, one opening 15a is formed at one end of the plate 15 and the other opening 15a is formed at the other end of the plate 15. Since the plate 15 is extended in the direction connecting these openings 15a, the plate 15 can be made compact to ensure minimal invasiveness.

  In the case of the present embodiment, the second shaft-like body 20B of the bone fixing member 20 is engaged with the cortex of the outer portion Y by the male screw 24 that is the second bone-engaging structure. By being fixed to the second shaft-like body 20B through the structure, it is indirectly fixed to the outer portion Y. Therefore, as in the first application mode, the head 25 and the plate 15 of the bone fixing member 20 on the outer portion Y protrude away from the outer portion Y, so that problems such as giving pain to the patient do not occur. Further, the adaptability to the shortening action (bone head shortening) in the bone healing process can be ensured by the sliding operation between the first shaft-like body 20A and the second shaft-like body 20B. Similarly, it is not necessary to slidably configure the second shaft-like body 20B and the bone portion on the surface side of the fracture line. Therefore, since the second shaft-like body 20B can be introduced in a manner that is sufficiently supported with respect to the bone portion, the relative posture between the plurality of bone fixing members 20 and 20 with respect to the load load Stiffness can be increased.

  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, each of the openings such as the openings 14a and 15a may have a notch shape instead of a complete hole shape. In addition, the first bone engagement structure provided in the first shaft-like body is not limited to the engagement hook portion of the above embodiment, and may be a structure in which the tip expands in all directions, It may be a screw or a blade.

  In the first application mode, contrary to FIG. 1, the bone fixing member 10 may be introduced on the distal side, and the bone fixing member 20 may be introduced on the proximal side. If either one of the bone fixing members 10 and 20 is a stretchable bone fixing member, the other may be a simple bone fixing member such as a bone screw or a hook pin. Similarly, in the second application mode, if either one of the two bone fixing members 20 is a telescopic bone fixing member, the other is a non-expandable bone fixing member such as a bone screw or a hook pin. It does not matter. However, in any of the above cases, it is desirable that the bone anchoring member that is not expandable / contractable is configured to engage only with the cortex near the surface of the bone.

  Further, the second shaft-like body 10B of the bone fixing member 10 has a structure in which the plate portion 14 is deleted and a head portion is provided at the base end of the barrel portion 13, and an independent plate indicated by a two-dot chain line in FIG. 15 may be used in place of the plate portion 14, and the head may be engaged with one opening 15 a of the plate 15. In this case, as a matter of course, it is preferable to form a locking male screw to be screwed into the internal thread 15b of the opening 15a at the head.

  In the above application mode, an example is shown in which the present invention is applied to the proximal part of the femur. However, the bone fixation system according to the present invention can be used for various fracture modes of each part by appropriately changing the dimensions. In particular, a great effect can be obtained by using it at the end of a long bone such as a femur or a humerus.

DESCRIPTION OF SYMBOLS 10 ... Bone fixing member, 10A ... 1st axial body, 10B ... 2nd axial body, 11 ... Sleeve, 11a ... Side part opening, 11b ... Inclined guide surface, 11c ... Base part opening, 11d ... Female thread part, 11e: Tool engaging portion, 11f: Retaining ring, 12 ... Pin, 12a ... Engaging hook portion, 12b ... Base end portion, 12c ... Male screw portion, 13 ... Barrel portion, 14 ... Plate portion, 14a ... Opening portion, 14b ... Internal thread, 15 ... Plate, 15a ... Opening, 15b ... Internal thread, 20 ... Bone fixing member, 20A ... First shaft-like body, 20B ... Second shaft-like body, 21 ... Sleeve, 21a ... Side opening, 21b ... Inclined guide surface, 21c ... Base opening, 21d ... Female thread part, 21e ... Tool engaging part, 21f ... Retaining ring, 22 ... Pin, 22a ... Engaging hook part, 22b ... Base end part, 22c ... Male thread part, 23 ... Barrel structure, 24 ... For bone engagement Male thread, 25 ... head, 25a ... male screw for locking

Claims (35)

A bone fixation system applied to bone for bone treatment,
A first shaft-like body disposed on the distal end side in the axial direction and having a first bone-engaging structure;
A second shaft-like body that is disposed on the base end side in the axial direction and constitutes a stretchable structure that can slide in the axial direction between the first shaft-like body, and
Including a telescopic bone anchoring member,
A bone fixation system characterized by that. Including the first extendable bone fixation member and the second extendable bone fixation member,
The proximal end portion of the second shaft-like body of the first extendable bone fixing member and the proximal end portion of the second shaft-like body of the second extendable bone fixing member are mutually Configured to be connectable in a removable manner,
The bone fixation system according to claim 1. The second shaft-like body of at least one of the first extendable bone fixing member and the second extendable bone fixing member is adjacent to the distal end side with respect to the base end portion. Having a second bone-engaging structure in position,
The bone fixation system according to claim 2. The first stretchable bone anchoring member and the second stretchable bone anchoring member are coupled in a manner in which the angle between the axes is fixed so as to have a predetermined posture relationship with each other.
The bone fixation system according to claim 2 or 3, characterized in that. The first stretchable bone fixation member and the second stretchable bone fixation member are coupled so that the axes extend in parallel to each other.
The bone fixation system according to any one of claims 2 to 4, wherein The extendable bone fixing member includes the first shaft-like body and the second shaft-like body in at least a part of a range in which the first shaft-like body and the second shaft-like body can slide in the axial direction. The second shafts are configured to be rotatable around the axis with respect to each other.
The bone fixation system according to any one of claims 2 to 5, wherein The first bone engagement structure is a movable engagement portion configured to be movable in a direction intersecting the axial direction.
The bone fixation system according to any one of claims 2 to 6, wherein The telescopic structure may be configured such that the base end of the first shaft-shaped body does not protrude toward the base end side from the base end of the second shaft-shaped body, or the base end of the first shaft-shaped body is The slidable range is limited so that the amount protruding toward the base end side from the base end of the second shaft-like body is limited.
The bone fixation system according to any one of claims 2 to 7, wherein The first telescopic bone fixing member has a plate portion projecting from a proximal end portion to at least one side of the axis, and the plate portion has an opening having a second axis extending in parallel with the axis. Part
The second telescopic bone fixing member includes a head provided at a proximal end of the second shaft-like body and engaged with the opening.
The bone fixation system according to claim 2. The second shaft-like body of the second extendable bone fixing member has a second bone engaging structure at a position adjacent to the distal end side with respect to the head.
The bone fixation system according to claim 9. The opening is a screw hole for locking with an internal thread,
The head is a male screw for locking that engages with the internal thread.
The bone fixation system according to claim 9. The second shaft-like body of the second extendable bone fixing member has a second bone engaging structure at a position adjacent to the distal end side with respect to the head, and the second bone engaging member. The combined structure is an external thread for engaging bone formed around the axis.
The bone fixation system according to claim 11. The bone engaging male screw has a screw structure having the same lead as the locking male screw.
The bone fixation system according to claim 12. The extendable bone fixing member includes the first shaft-like body and the second shaft-like body in at least a part of a range in which the first shaft-like body and the second shaft-like body can slide in the axial direction. The second shafts are configured to be rotatable around the axis with respect to each other.
The bone fixation system according to any one of claims 9 to 13, wherein The first bone engagement structure is a movable engagement portion configured to be movable in a direction intersecting the axial direction.
The bone fixation system according to any one of claims 9 to 14, wherein The telescopic structure may be configured such that the base end of the first shaft-shaped body does not protrude toward the base end side from the base end of the second shaft-shaped body, or the base end of the first shaft-shaped body is The slidable range is limited so that the amount protruding toward the base end side from the base end of the second shaft-like body is limited.
The bone fixation system according to any one of claims 9 to 15, wherein The second shaft-like body has a plate portion that protrudes from a base end portion to at least one side of the axis, and the plate portion includes an opening having a second axis extending in parallel with the axis. ,
The bone fixation system according to claim 1. A head portion provided at a proximal end engages with the opening of the plate portion, and is configured to be connectable to the extendable bone fixing member in a posture extending along the second axis. Further comprising another bone anchoring member,
The bone fixation system according to claim 17. The other bone fixing member includes a second bone engaging structure at a position adjacent to the distal end side with respect to the head.
The bone fixation system according to claim 18, wherein: The second bone engaging structure is a male screw for engaging bone formed around the second axis.
The bone fixation system according to claim 19. The opening is a screw hole for locking with an internal thread,
The head includes a locking external screw that is screwed into the internal thread.
The bone fixation system according to any one of claims 18 to 20, wherein The extendable bone fixing member includes the first shaft-like body and the second shaft-like body in at least a part of a range in which the first shaft-like body and the second shaft-like body can slide in the axial direction. The second shafts are configured to be rotatable around the axis with respect to each other.
The bone fixation system according to any one of claims 17 to 21, characterized in that The first bone engagement structure is a movable engagement portion configured to be movable in a direction intersecting the axial direction.
The bone fixation system according to any one of claims 17 to 22, wherein The telescopic structure may be configured such that the base end of the first shaft-shaped body does not protrude toward the base end side from the base end of the second shaft-shaped body, or the base end of the first shaft-shaped body is The slidable range is limited so that the amount protruding toward the base end side from the base end of the second shaft-like body is limited.
The bone fixation system according to any one of claims 17 to 23, wherein Of the bottom surface of the plate portion, the first surface portion around the position through which the axis of the extendable bone fixing member passes and the position around the position through which the second axis of the opening passes. At least one of the second surface portions has a difference in surface shape on both sides in the width direction when viewed in the width direction intersecting at least the direction connecting the axis and the second axis. Composed,
25. The bone fixation system according to any one of claims 9 to 24. The second shaft-like body is provided with a head at the proximal end and a second bone engaging structure at a position adjacent to the distal end side with respect to the head.
The bone fixation system according to claim 1. The second bone engaging structure is a male screw for engaging bone formed around the axis.
27. The bone fixation system of claim 26. And further comprising a plate with an opening engageable with the head.
28. A bone fixation system according to claim 26 or 27. The opening is a screw hole for locking with an internal thread,
The head includes a locking external screw that is screwed into the internal thread.
29. A bone fixation system according to claim 28. The extendable bone fixing member includes the first shaft-like body and the second shaft-like body in at least a part of a range in which the first shaft-like body and the second shaft-like body can slide in the axial direction. The second shafts are configured to be rotatable around the axis with respect to each other.
30. A bone fixation system according to any one of claims 26 to 29. The first bone engagement structure is a movable engagement portion configured to be movable in a direction intersecting the axial direction.
The bone fixation system according to any one of claims 26 to 30, wherein The telescopic structure may be configured such that the base end of the first shaft-shaped body does not protrude toward the base end side from the base end of the second shaft-shaped body, or the base end of the first shaft-shaped body is The slidable range is limited so that the amount protruding toward the base end side from the base end of the second shaft-like body is limited.
32. The bone anchoring system according to any one of claims 26 to 31. The extendable bone fixing member includes the first shaft and the second shaft in a part of a range in which the first shaft and the second shaft can slide in the axial direction. Two shafts are configured to be rotatable around the axis,
The extendable bone fixing member includes the first shaft-like body and the second shaft-like body in a portion other than the part in a range in which the first shaft-like body and the second shaft-like body can slide in the axial direction. The shaft-shaped body and the second shaft-shaped body are configured such that rotation about the axis is mutually restricted.
The bone fixation system according to any one of claims 1 to 32, wherein The extendable bone fixing member is configured such that the first shaft-like body and the second shaft-like body can rotate around the axis line,
The extendable bone fixing member is configured such that the first shaft and the second shaft are in a state in which the first shaft and the second shaft can rotate around the axis. A rotation restricting means capable of shifting to a state in which the rotation of the rods around the axis is restricted;
The bone fixation system according to any one of claims 1 to 32, wherein The movable engagement portion is an engagement hook configured to be able to appear and retract in a direction intersecting the axial direction.
32. A bone fixation system according to claim 7, 15, 23 or 31.

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