Bone surgery guide

Abstract

To reduce a risk of bone fracture of a rough surface part of a bone and bone fracture in a hinge part (a distal end in an opened part) and a diaphysis.SOLUTION: A bone surgery guide includes: an index pin 2 that is implanted to a predetermined implantation point in a bone as an index of osteotomy; a slit part 3 that guides implantation of a bone saw 5 to the bone; and a guide part 4 that guides the slit part 3, the guide part 4 including a movable member 13 that supports the index pin 2 and is movable along an arc plane around the implantation point of the index pin 2 to the bone.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a guide for bone surgery that is suitable for use in biplanar osteotomy and the like. [Background technology]

[0002] In knees that have been deformed due to osteoarthritis or other conditions, the stress on the knee is concentrated on one side, and it is common to see damage to only the cartilage on one side.

[0003] Knee osteotomy is a procedure in which an incision is made in the tibia or femur, and the bone is opened or closed to correct the alignment of the knee and shift the position of weight bearing to a pain-free area.

[0004] For example, in a bone opening procedure, the tip of a cut made in the bone is used as a rotation axis to open and correct the bone. In this method, a gap is created in the opened bone after alignment correction, so in order to maintain the corrected position, metal plates and screws are used to fix the bone, and artificial bone is filled in and reinforced in the gap.

[0005] Regarding osteotomy around the knee for osteoarthritis of the knee, historically, treatment began as monoplane osteotomy, in which an incision is made in the transverse plane (see Non-Patent Document 1 below).

[0006] Subsequently, in addition to transverse osteotomy, a surgical technique in which the tibial tuberosity is cut proximally in the coronal plane direction (ascending osteotomy) and a surgical technique in which the tibial tuberosity is cut distally (descending osteotomy) have been developed as biplane osteotomies, with the aim of improving the rotational stability of the osteotomy site, assisting with sagittal plane inclination, and achieving early bone union by increasing the contact area of ​​the osteotomy surface (see non-patent documents 2 and 3 below). [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] MB Coventry et al. “Osteotomy of the Upper Portion of the Tibia for Degenerative Arthritis of the Knee”, J. Bone Joint Surg., 47 (5), 984-990 (1965) [Non-Patent Document 2] P. Lobenhoffer et al. “Improvements in surgical technique of valgus high tibial osteotomy”, Knee Surg. Sports Traumatol. Arthrosc., 11, 132-138 (2003) [Non-Patent Document 3] RDA Gaasbeek et al. “Distal tuberosity osteotomy in open wedge high tibial osteotomy can prevent patella infera: a new technique”, Knee, 11 457-461 (2004) Summary of the Invention [Problem to be solved by the invention]

[0008] For example, in a high tibial osteotomy (HTO) for the tibia, if the ascending osteotomy line or descending osteotomy line near the tibial tuberosity is too far forward of the tibia, i.e., if the thickness of the tuberosity becomes too thin, the risk of fracture of the tuberosity increases. Conversely, if the line is too far backward of the tibia, i.e., if the thickness of the tuberosity becomes too thick, the risk of fracture at the hinge portion (tip of the opening) or shaft increases.

[0009] The optimal positions of the Ascending Osteotomy Line and the Descending Osteotomy Line, i.e., the optimal thickness of the tibial tuberosity, depend on the patient's bone morphology, bone quality, bone density, etc., and therefore cannot be generally determined.

[0010] Furthermore, when inserting the bone saw from the inside to the outside of the tibia, it is difficult to check the insertion angle of the bone saw, so it is extremely difficult for the surgeon to advance the bone saw in the direction intended.

[0011] In view of the above, an object of the present invention is to provide a bone surgery guide that can reduce the risk of fractures in the tuberosity of a bone, as well as fractures in the hinge portion (the tip of the opening portion) and the bone shaft. [Means for solving the problem]

[0012] In order to achieve this objective, the present invention provides a bone surgery guide for guiding the cutting edge of a bone saw to an arbitrary point or to a plane passing through that point, characterized in that it comprises an index pin that is inserted into a predetermined insertion point of the bone as an index for bone cutting, a slit portion having a bone saw guide portion that guides the insertion of the bone saw into the bone, and a guide portion that supports the index pin and guides the slit portion so that the arbitrary point of the index pin is positioned on an extension line of the bone saw guide portion.

[0013] In the present invention, the slit portion is characterized by having at least one pin insertion portion into which a pin for fixing the slit portion to a bone is extended.

[0014] In addition, the present invention is characterized in that the guide portion has a movable member that is movable along an arc plane centered on the arbitrary point of the index pin, and the slit portion can be rotated around the arbitrary point.

[0015] In the present invention, the index pin may further include a restricting portion that restricts an extension length from a support position on the guide portion to a tip position of the index pin to a predetermined length.

[0016] In the present invention, the slit portion may include a transverse cross-sectional slit, and a distal slit or a proximal slit adjacent to the transverse cross-sectional slit.

[0017] In the present invention, the slit portion is characterized by having a transverse cross-sectional slit, a distal slit adjacent to the transverse cross-sectional slit, and a proximal slit adjacent to the transverse cross-sectional slit on the opposite side to the distal slit.

[0018] In addition, in the present invention, the guide portion comprises an arc-shaped outer shell arm having an arc-shaped groove, an arc-shaped inner shell member movably incorporated into the arc-shaped groove of the arc-shaped outer shell arm as the movable member supporting the index pin, a movable member fixing means for releasably fixing the arc-shaped inner shell member at a desired position in the arc-shaped groove of the arc-shaped outer shell arm, an index pin fixing means for releasably fixing the index pin to the arc-shaped inner shell member, an arm holding member for supporting the arc-shaped outer shell arm so that it can be moved forward and backward relative to the bone, and an arm holding member fixing means for releasably fixing the arm holding member at a desired forward and backward position.

[0019] In the present invention, the index pin is characterized by having an insertion indicator portion that indicates a predetermined insertion depth into the bone. Effect of the Invention

[0020] According to the present invention, by providing the above-mentioned configuration, it is possible to reduce the risk of fractures in the tuberosity of the bone, as well as fractures in the hinge portion (the tip of the opening portion) and the diaphysis. [Brief description of the drawings]

[0021] [Figure 1] 1 is a perspective view showing a bone surgery guide according to an embodiment of the present invention; [Diagram 2]1 is an explanatory diagram showing a state in which the bone surgery guide of the present embodiment is used; [Diagram 3] FIG. [Figure 4] FIG. 13 is a side view showing a modified example of the index pin. [Diagram 5] FIG. 5A is a perspective view showing a slit portion, and FIG. 5B is a plan view of FIG. 5A. [Figure 6] FIG. 13 is a perspective view showing a modified example of the slit portion. [Figure 7] FIG. 13 is a perspective view showing a modified example of the slit portion. [Figure 8] FIG. 11 is a side view showing a modified example of the slit portion. [Figure 9] FIG. 11 is a side view showing a modified example of the slit portion. [Figure 10] FIG. 11 is a side view showing a modified example of the slit portion. [Figure 11] FIG. 11 is a side view showing a modified example of the slit portion. [Figure 12] 12A is a perspective view showing a guide portion, and FIG. 12B is an exploded perspective view of FIG. 12A. [Figure 13] FIG. 13 is a perspective view showing a modified example of the guide portion. [Figure 14] FIG. 13 is a perspective view showing a modified example of the guide portion. [Figure 15] FIG. [Figure 16] FIG. 13 is a side view of another embodiment of a bone surgical guide in use. [Figure 17] FIG. 17 is a perspective view of the bone surgical guide of FIG. 16 . [Figure 18] 18A is a perspective view showing a modified example of a slit portion, and FIG. 18B is an explanatory cross-sectional view of the slit portion of FIG. 18A. [Figure 19] FIG. 13 is a perspective view showing another modified example of the slit portion. [Figure 20] FIG. 4 is a diagram showing a position scale provided on a guide portion. [Figure 21] 11 is an explanatory diagram showing a state in which the bone surgery guide of this embodiment and another embodiment are connected to each other and used. FIG. [Figure 22] 22 is an explanatory diagram showing a modified example of the main part of the bone surgery guide of FIG. 21. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] An embodiment of the present invention will be described with reference to the drawings. When cutting up the vicinity of the tibial tuberosity toward the proximal side (Ascending Osteotomy) or cutting down toward the distal side (Descending Osteotomy), the cutting edge of the bone saw inserted for bone cutting is guided to face the insertion point of the pin inserted into the bone as an index (or an extension line on the coronal plane passing through the insertion point) regardless of the insertion start position, thereby making it possible to adjust the tuberosity to any thickness while ensuring the anterior-posterior width of the hinge part.

[0023] This is expected to reduce the risk of fractures at the tuberosity, hinge area (tip of the opening), and shaft.

[0024] The bone surgery guide 1 of this embodiment includes an index pin 2, a slit portion 3, and a guide portion 4, as shown in FIG.

[0025] When using the bone surgery guide 1, as shown in Figs. 2A to 2C, the index pin 2 is inserted into a bone as an index, a bone saw 5 is passed through the slit portion 3, and the bone saw 5 is guided by the slit portion 3 to cut into the bone.

[0026] As shown in Fig. 1, the guide section 4 includes a moving member (an arc-shaped inner shell member 13, described later) and guides the slit section 3. As shown in Figs. 2A to 2C, the moving member (an arc-shaped inner shell member 13) moves along an arc plane centered on the insertion point of the index pin 2 into the bone. The slit section 3 guided by the guide section 4 guides the cutting edge of the bone saw 5 to a point on the bone surface (the insertion point of the index pin 2 into the bone) or to an extension line on the coronal plane passing through that point when cutting up toward the proximal side in the coronal plane direction near the tibial tuberosity or cutting down toward the distal side.

[0027] As shown in Fig. 1, the index pin 2 is held by a movable member (arc-shaped inner shell member 13) of the guide part 4. The index pin 2 is inserted, for example, near the knee joint to serve as an index for osteotomy. More specifically, the pin is inserted perpendicularly to the coronal plane into the medial and lateral sides of the proximal tibia or the medial and lateral sides of the distal femur.

[0028] As shown in Fig. 3, the index pin 2 in this embodiment includes a shaft portion 2a having a sharp tip, and a first stopper 2b provided as an insertion instruction portion and having a larger diameter than the shaft portion 2a. The first stopper 2b has a larger diameter than the shaft portion 2a, and this allows the insertion depth of the index pin 2 into the bone to be restricted at a predetermined position. As another insertion instruction, a marking indicating the insertion depth into the bone may be provided instead of the first stopper 2b, although this is not shown.

[0029] 4, a second stopper 2c protruding outward as a restricting portion may be provided on the base end side (the side held by the arc-shaped inner shell member 13) of the index pin 2. The second stopper 2c restricts the index pin 2 so that the index pin 2 does not move relative to the moving member (the arc-shaped inner shell member 13) of the guide portion 4 when the index pin 2 is inserted into the bone.

[0030] 5A, the slit portion 3 has a transverse cross-sectional slit 6 and a distal slit 7. The transverse cross-sectional slit 6 and the distal slit 7 each have a bone saw guide portion 8 for guiding the bone saw 5.

[0031] 5B, the transverse cross-sectional slit 6 and the distal slit 7 are integrally connected to each other at an angle θ1. Specifically, the angle θ1 is set to 90° to 20°, preferably 90° to 45°, and more preferably 80° to 50°.

[0032] 6, the slit section 3 may include a transverse cross-sectional slit 6 and a proximal slit 9. The angle between the transverse cross-sectional slit 6 and the proximal slit 9 is specifically set to 120° to 20°, preferably 110° to 30°, and more preferably 110° to 45°.

[0033] As shown in FIG. 7, the slit portion 3 may be integrally provided with the transverse cross-sectional slit 6, the distal slit 7, and the proximal slit 9.

[0034] Also, the bone saw guide 8 may be continuous between the transverse slit 6 and the distal slit 7 (or the proximal slit 9) as shown in Fig. 8, or may be open at the end of the distal slit 7 (or the proximal slit 9) or at the end of the transverse slit 6 as shown in Fig. 9. Furthermore, as shown in Fig. 10, not only may the end of the distal slit 7 (or the proximal slit 9) be open, but also the upper end may be cut out.

[0035] Furthermore, the slit portion 3 may be provided with a pin insertion portion 10 along the bone saw guide portion 8 of the cross-sectional slit 6 as shown in FIG.

[0036] As shown in Figures 12A and 12B, the guide portion 4 comprises an arc-shaped outer shell arm 11 having an arc-shaped groove, an arc-shaped inner shell member 13 that supports the index pin 2 and is movably incorporated into the arc-shaped groove 12 of the arc-shaped outer shell arm 11, and an arm holding member 14 that supports the arc-shaped outer shell arm 11 so that it can move freely forward and backward relative to the bone.

[0037] Furthermore, the guide portion 4 includes a first fixing screw 15 (moving member fixing means) that releasably fixes the arc inner shell member 13 at a desired position in the arc-shaped groove 12 of the arc outer shell arm 11, a second fixing screw 16 (index pin fixing means) that releasably fixes the index pin 2 to the arc inner shell member 13, and a third fixing screw 17 (arm holding member fixing means) that releasably fixes the arm holding member 14 at a desired advance / retreat position. The arm holding member 14 has an engagement portion with the arc outer shell arm 11 and an engagement portion with the slit portion 3.

[0038] The arc outer shell arm 11 is provided with an angle scale 18 that determines the angle at which the bone saw 5 is inserted into the bone. The arc outer shell arm 11, the arc inner shell member 13, and the arm holding member 14 move on the same plane. The arc outer shell arm 11 and the arc inner shell member 13 are formed on an arc with a radius starting from the insertion point of the index pin 2 into the bone.

[0039] Although not shown, the arc-shaped inner shell member 13 may be formed by combining two or more members. Furthermore, although not shown, a ratchet mechanism or the like that can fix the arc-shaped inner shell member 13 at any position may be provided instead of the first fixing screw 15 as the movable member fixing means.

[0040] As shown in FIG. 13, the slit portion 3 and the guide portion 4 may be integrally formed.

[0041] As another embodiment, a guide section 21 having a configuration shown in Fig. 14 can be adopted. As shown in Figs. 14 and 15, the guide section 21 moves on an arc surface of an arbitrary radius from a specific point on the bone surface by covering a tubular member 22 integrated with an arc inner shell member 13 over a rod-like member 23 (not limited to the index pin 2 of the present invention) inserted into the bone.

[0042] As an embodiment other than the above, it is also possible to adopt the configurations shown in Figures 16 and 17. That is, the bone surgery guide 30 includes an index pin 31 to be inserted into the bone as an index for bone cutting, a slit portion 32 into which the bone saw 5 is inserted for bone cutting, and a guide portion 33 integrally connected to the slit portion 32, and includes an engagement portion 34 for engaging the index pin 2 with the guide portion 33.

[0043] When performing osteotomy of the anterior tibia in an arc shape relative to the coronal plane, the bone surgery guide 30 of this configuration guides the cutting edge of the bone saw along an arc shape centered on any point on the bone surface (the insertion point of the index pin 31 into the bone) and along a plane inclined relative to the coronal plane.

[0044] As shown in Fig. 17, the slit portion 32 is formed with a bone saw guide portion 35. As shown in Fig. 16, the insertion angle θ2 of the bone saw guided by the bone saw guide portion 35, that is, the angle θ2 between the perpendicular direction to the coronal plane and the depth direction of the bone saw guide portion 35, is preferably set to be greater than -45° and smaller than 45°, more preferably greater than 0° and smaller than 30°.

[0045] As shown in Figs. 18A and 18B, a slit portion 37 may be provided in which a plurality of (two in the figure) bone saw guide portions 36a, 36b having different insertion angles for the bone saw are formed.

[0046] Also, as shown in FIG. 19, the guide portion 38 and the slit portion 39 may be connected via a hinge 40 such as a tightening screw, so that the slit portion 39 can be adjusted to any angle relative to the guide portion 38.

[0047] As shown in FIG. 20, the guide portion 33 may have a position scale 41 that serves as a guide for adjusting the arc radius.

[0048] 16 to 20 can be used by attaching an engagement portion 34 to the index pin 2 of the bone surgery guide 1 shown in Fig. 1, as shown in Fig. 21A to 21C. In this case, the engagement portion 34 may be provided on the arc-shaped inner shell member 13, as shown in Fig. 22. [Explanation of symbols]

[0049] 1,30…Bone surgery guide 2,31…Index pin 2b…First stopper (insertion guide part) 2c…Second stopper (regulating part) 3, 32, 37, 39…Slit section 4,21,38…Guide section 5. Bonesaw 6...Cross-section slit 7…Distal slit 8,35,36a,36b…Bone saw guide 9…Proximal slit 10…Pin insertion part 11...Arc outer shell arm 12...Groove 13...Arc inner shell member (moving member) 14...Arm holding member 15...First fixing screw (moving member fixing means) 16...Second fixing screw (index pin fixing means) 17...Third fixing screw (arm holding member fixing means)

Claims

1. A bone surgery guide for guiding the cutting edge of a bone saw to an arbitrary point or a plane passing through the arbitrary point, An index pin that is inserted into a predetermined insertion point of the bone as an index for osteotomy; A slit portion having a bone saw guide portion for guiding the bone saw into the bone; a guide portion that supports the index pin and guides the slit portion so that an arbitrary point of the index pin is positioned on an extension line of the bone saw guide portion; A bone surgery guide comprising:

2. 2. The bone surgical guide according to claim 1, A bone surgical guide, wherein the slit portion includes at least one pin insertion portion into which a pin for fixing the slit portion to a bone is extended.

3. 3. The bone surgical guide according to claim 2, A bone surgery guide characterized in that the guide portion has a movable member that can move along an arc plane centered on the arbitrary point of the index pin, and the slit portion can be rotated around the arbitrary point.

4. 3. The bone surgical guide according to claim 2, The bone surgery guide, wherein the index pin is provided with a restricting portion that restricts an extension length from a support position on the guide portion to a tip position of the index pin to a predetermined length.

5. 3. The bone surgical guide according to claim 2, The slit portion includes a transverse slit and a distal slit or a proximal slit adjacent to the transverse slit.

6. 3. The bone surgical guide according to claim 2, The slit portion comprises a transverse slit, a distal slit adjacent to the transverse slit, and a proximal slit adjacent to the transverse slit on the opposite side to the distal slit.

7. 3. The bone surgical guide according to claim 2, The guide portion includes an arcuate outer shell arm having an arcuate groove; an arcuate inner shell member movably fitted in the arcuate groove of the arcuate outer shell arm as the moving member supporting the index pin; a movable member fixing means for releasably fixing the inner shell member at a desired position in the arc-shaped groove of the outer shell arm; an index pin fixing means for releasably fixing the index pin to the arc-shaped inner shell member; an arm holding member that supports the arcuate outer shell arm so as to be freely advanced and retreated relative to a bone; and an arm holding member fixing means for releasably fixing the arm holding member at a desired advance / retract position.

8. The bone surgery guide according to any one of claims 1 to 7, The index pin is provided with an insertion indicator portion that indicates a predetermined insertion depth into the bone.

Images