Bone resection retractor

Abstract

To provide a spreader that makes it extremely easy to perform an operation of fitting a pair of swing members to a notch of a bone and removing them after insertion of a transplant.SOLUTION: A spreader 100 is constituted by a first structure 10 and a second structure 20 whose side surfaces can be engaged with each other. The first structure includes: a hinge part that vertically rotatably couples ends of upper and lower swing bodies; an opening / closing mechanism, in the vicinity of ends on an opposite side, for spreading a notch of a tibia by adjusting an angle between the first upper and lower swing bodies; and a first engaging member, provided on the opening / closing mechanism, for engaging the second structure's side surface with the first structure's side surface before inserting the spreader into the notch. The second structure includes: a hinge part that vertically rotatably couples upper and lower swing bodies at one ends of the upper and lower swing bodies; a second engaging member for engaging with the first engaging member at an end on the opposite side; and a mechanism for releasing the second engaging member from the first engaging member to remove the second structure from the notch.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to the structure of an osteotomy speculum for use in inserting a graft into an incision made in the tibia for the treatment of a patient with osteoarthritis of the knee. [Background technology]

[0002] Conventionally, high tibial osteotomy (HTO) has been performed on the high tibia to correct the angle of the deformed femur or tibia of patients with osteoarthritis of the knee. One method of high tibial osteotomy is the open wedge method. As shown in Figure 1, this is a treatment method in which the upper part of the tibia 1, which constitutes one of the knee joints of a patient with osteoarthritis of the knee, is resected using a bone saw, and a wedge-shaped bone graft or artificial bone graft is inserted into the incision 3 to correct the angle of the femur or tibia when standing.

[0003] To insert a transplant into the formed incision 3, the incision 3 is enlarged using a tool (a dilator), and the transplant is inserted to a specified position while maintaining this state. When the insertion is completed, the dilator is removed to complete the process. However, when inserting a transplant while the incision is enlarged with the dilator, there is a problem that the dilator itself becomes an obstacle to insertion. To avoid this problem, it has been conventional to make the swinging part of the dilator (the blade inserted into the incision) into two parts in the width direction (Patent Documents 1 to 3). After inserting a pair of such swinging parts into the incision and enlarging it, one of the swinging parts is removed and the transplant is inserted into the incision maintained by the other swinging part. Then, this inserted graft maintains the enlarged incision, so the remaining swinging part is removed. The incision into which the transplant has been inserted is covered and fixed from the outside with a metal plate or the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4736091 [Patent Document 2] Patent No. 6626474 [Patent Document 3] JP 2016-209435 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a pair of these swinging members are used as an integrated unit, a mechanism for engaging the two is provided to perform the insertion operation and the operation of enlarging the incision in conjunction. For example, in Patent Document 1, a protrusion is provided on the side of the first swinging member, and a recess is provided on the opposing side of the second swinging member, and the two are integrated by fitting them together. A first opening and closing mechanism (rod-shaped screw) is provided near the tip on the opposite side to the hinge part that rotatably connects the first upper and lower swinging members, and when the dilator is opened by this, the first and second upper and lower swinging members are linked and open to a predetermined angle. Next, a similar screw-shaped second opening and closing mechanism provided on the second swinging member is rotated to fix the above-mentioned predetermined angle between the second upper and lower swinging members, and then the first swinging member is removed, and the incision is supported by the second swinging member to insert the graft. After the insertion is completed, the second opening and closing mechanism is rotated to reduce the angle, and the second swinging member is removed, completing the series of operations. However, when fixing the second oscillating member at a predetermined angle, and when removing the second oscillating member after insertion is complete, it is necessary to rotate the screw, which results in a problem that the operation is time-consuming and laborious.

[0006] In addition, the dilator of the literature 2 firstly engages the first and second blades (swinging members) 21A and 21B in a common groove on the back of both blades by sliding the first connecting member 5, and then connects the first and second blades in advance by penetrating the second connecting member 6 through the through holes on the side of both swinging members to integrate the first and second blades. After enlarging the incision in the bone in this state, the first and second connecting members 5 are removed while maintaining this state, and the first blade is closed and removed. Then, the graft is inserted while maintaining the expanded state only with the second blade, and the second blade is closed and removed to complete the operation. However, such a series of operations requires an operation of engaging the first and second blades in advance with the first and second connecting members 5, and then an operation of removing the first and second connecting members 5 while maintaining the incision width and separating the first and second blades, which is problematic in that it takes time and effort to complete the series of operations.

[0007] As described above, osteotomy expanders have the problem that after expanding the tibial incision, the operation of leaving the pair of oscillating members or spacing members in the incision to maintain the expanded state, and the operation of removing the pair of oscillating members are complicated, lengthening the treatment time.

[0008] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a dilator which has a pair of swinging members attached to an incision in a bone and which allows an implant to be inserted and then removed with great ease. [Means for solving the problem]

[0009] The dilator of the present invention has the following configuration. A retractor for osteotomy used in a treatment for correcting the angle of the tibia by inserting a graft into an incision made in the tibia of a patient with osteoarthritis of the knee, comprising: The dilator is composed of a first structure and a second structure whose respective sides are engageable with each other, the first component has first upper and lower swinging bodies, one end of which is connected by a first hinge portion so as to be rotatable in the vertical direction, and an opening / closing mechanism for adjusting an angle between the first upper and lower swinging bodies is provided near an end of the first upper and lower swinging bodies opposite the first hinge portion, and a first engagement member for engaging the second component with a side surface of the first component before insertion into the notch is provided on the opening / closing mechanism; The second component has a second upper and lower rocking body, one end of which is connected by a second hinge portion so as to be rotatable vertically, and the end of the second upper and lower rocking body opposite the second hinge portion is provided with a second engagement member for engaging the first component, and both of the second upper and lower rocking bodies are provided with a mechanism for releasing the second engagement member from the first engagement member after the notch is enlarged.

[0010] The second engaging member is a protrusion protruding upward from the second vertical swinging body, and the releasing mechanism is a lever provided at the tip of the upper side of the second vertical swinging body and a lever-type hook member provided at the lower side of the second vertical swinging body, the first engagement member includes a hook receiving member provided on the opening / closing mechanism, the upper hook receiving member of the first vertical swinging body has a groove for receiving the protrusion in the direction of the hinge portion, and the lower hook receiving member of the first vertical swinging body has a recess for fitting with the tip of the lever-type hook member, By manipulating the lever and the lever-type hook member, the second engagement member can be engaged with and disengaged from the first engagement member.

[0011] The opening and closing mechanism may be composed of a cylindrical body that penetrates the first upper and lower rocking bodies and has a screw thread on its surface, and a rotating member that has through holes in each of the first upper and lower rocking bodies and has a screw groove on its inner surface that fits with the screw thread of the cylindrical body, and has a rotation axis in the lateral direction of the cylindrical body and the first upper and lower rocking bodies. Effect of the Invention

[0012] According to the present invention, the complicated operation involved in the conventional high tibial osteotomy can be eliminated, and an easy-to-operate retractor can be provided, thereby shortening the time required for the procedure. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 illustrates the incisions made into the bone below the knee joint for a high tibial osteotomy (HTO). [Diagram 2] FIG. 2 is a perspective view of the appearance of a dilator according to the present invention. [Diagram 3] FIG. 3 is a side view of a first arrangement of a dilator according to the present invention. [Figure 4] FIG. 4 is a side view of a second configuration of a dilator according to the present invention. [Diagram 5] FIG. 5 is a top view of a dilator according to the present invention and a partially enlarged view thereof. [Figure 6] FIG. 6 shows the state in which an incision is being enlarged using a speculum according to the present invention. [Figure 7] FIG. 7 shows the second component of the dilator according to the present invention being removed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] FIG. 2 shows a perspective view of the appearance of a dilator for HTO according to the present invention (hereinafter referred to as dilator) 100. The dilator 100 is composed of a first component 10 and a second component 20. Metals such as stainless steel and titanium are used as materials. As shown in FIG. 3, the first component 10 has a pair of upper and lower oscillating members 11 connected at one end by a first hinge portion 13 so that they can rotate in the vertical direction. The upper surface of the upper oscillating portion is provided with multiple lateral grooves to prevent slipping when holding the incision. The width of the second component side of the upper oscillating portion is narrowed to facilitate the insertion operation of a bone graft, ceramics, or other implant after removing the second component.

[0015] An operating section 14 is formed at the end of the upper and lower swing members 11 opposite to the hinge section 13. An opening / closing mechanism 15 is provided in the operating section 14 so as to penetrate the upper and lower swing members 11. The opening / closing mechanism 15 is cylindrical, and a helical screw thread 16 is provided from a little above the center point to the upper end, and a helical screw thread 16 is provided from a little below the center point to the lower end in the opposite direction to the upper screw. Therefore, when the center of the opening / closing mechanism 15 is manually rotated in one direction, the upper and lower screws rotate in the opposite direction, so that the upper and lower swing members 11 move in the opposite directions to each other, and the angle 12 between the first and second swing members 11 can be adjusted. The operating sections 14 of the upper and lower swing members 11 are provided with a passage opening through which the opening / closing mechanism 15 passes and a rotating part 19 having a horizontal rotation axis. The passage opening is provided with a female thread that fits with a screw thread 16 of the opening / closing mechanism 15, and the rotating part rotates in response to the up and down movement of the oscillating member, so that the upper and lower oscillating members 11 open and close following the movement of the opening / closing mechanism 15. Furthermore, the operating parts 14 of the upper and lower oscillating members 11 are provided with hook receiving members 17 (first engaging members) for engaging with a second component, which are integral with the opening / closing mechanism 15 and the rotating part 19.

[0016] FIG. 4 shows a side view of the second component. As with the first component, a pair of upper and lower swinging members 21 are connected at one end by a second hinge portion 23 so as to be rotatable in the vertical direction. In addition, the upper surface of the upper swinging member is provided with a plurality of horizontal grooves for preventing slippage as described above. The upper swinging member is provided with a T-shaped hook member 25 (second engagement member) for engaging with the first engagement member in the operation portion 24 at the end opposite to the second hinge portion 23. Furthermore, a lever 26 is provided at the uppermost end, and a lever-type hook member 27 is provided at the lowermost end. The lever-type hook member 27 is hammer-shaped with one end being hook-shaped, and its tip can be hooked into a recess provided in the lower hook receiving member 17, thereby locking the second component to the first component. The upper end is lever-shaped so as to be gripped with fingers, and the lock can be released by pinching and applying pressure between them. The first and second components can be easily integrated by holding and operating the lever 26 and the lever-type hook member 27 with one hand, hooking the T-type hook member 25 onto the hook receiving member 17 of the first component 10, and locking it with the lever-type hook member 27. Moreover, the integration can be easily performed by performing the opposite operation.

[0017] FIG. 5 shows a top view of the engaged state. The T-shaped hook member 25 can be attached by sliding it into the opening 18 of the hook receiving member 17. The hook receiving member 17 is provided to protrude toward the second construct so as to cover the second construct, and a groove is provided in the length direction of the second construct, and the opening 18 is provided in a direction in which the second construct 20 is pulled out from the incision in the tibia when the first and second constructs are separated during the procedure. Meanwhile, a recess is provided on the side of the T-shaped hook member 25, so that the T-shaped hook member 25 is fixed in the vertical direction when it is fitted into the groove from the opening 18. The T-shaped hook member 25 thus engaged can be easily removed from the hook receiving member 17 by holding the lever 26 and the lever-shaped hook member 27 and pulling them out of the opening 18. In this way, the first and second constructs can be separated extremely easily compared to the conventional engagement structure.

[0018] The method of using the dilator 100 of the present invention will be described with reference to Figs. 6 and 7. First, as shown in Fig. 6, the first and second components, which have been hooked and engaged with the T-shaped hook member 25 on the hook receiving member 17 as described above, are inserted deep into the incision 3 after rotating the opening / closing mechanism 15 to simultaneously make the angle 12 between the first and second upper and lower swinging members sufficiently small. Then, the opening / closing mechanism 15 is rotated to simultaneously expand the angle 12 between the first and second swinging members until the interval between the incisions becomes a predetermined interval. Then, as shown in Fig. 7, while maintaining this expanded state, the lever 26 and the lever-type hook member 27 of the second component 20 are operated with one hand to release the T-shaped hook member 25 from the hook receiving member 17, and the second component 20 is pulled out from the incision. After inserting the transplant into the expanded incision, the opening / closing mechanism 15 of the first component 10 is loosened and the first component 10 is pulled out from the incision 3, completing the procedure. In this manner, the operation of removing the first component from the notch can be performed simply by operating lever 26 and lever-type hook member 27 with one hand.

[0019] Although the present invention has been described based on the above embodiment, it will be apparent to those skilled in the art that the present invention is not limited thereto, and various changes and modifications can be made within the spirit of the present invention and the scope of the appended claims.

[0020] For example, although the above embodiment has been described with reference to an operation for cutting the tibia, it goes without saying that the invention can also be applied to osteotomies of other bones, such as the femur.

[0021] In addition, in the above embodiment, a long and thin cylindrical body having a screw thread is used as the opening and closing mechanism, but any mechanism can be used as long as the angle between the first upper and lower rocking bodies can be adjusted and fixed.

[0022] In the above embodiment, the first structure has a hook receiving member, and the second structure has a T-shaped hook member and a lever-shaped hook member, but the second structure may have a hook receiving member, and the first structure may have a T-shaped hook member and a lever-shaped hook member. The engaging members may have shapes other than those in the above embodiment. [Explanation of symbols]

[0023] 1 tibia 2 fibula 3 Cutting 100 Opener 10 First construct 20 Second construct 11, 21 Swinging member 12 Angle between the upper and lower oscillating members 13, 23 Hinge part 14, 24 Operation section 15 Opening and closing mechanism 16 threads 17 Hook receiving member 18 Openings 25 T-hook member 26 Lever 27 Lever-type hook member

Claims

1. A retractor for osteotomy used in a treatment for correcting the angle of the tibia by inserting a graft into an incision made in the tibia of a patient with osteoarthritis of the knee, comprising: The dilator is comprised of a first structure and a second structure, each of which has a side surface engageable with each other, the first component has first upper and lower swinging bodies, one end of which is connected by a first hinge portion so as to be rotatable in the up and down direction, and an opening and closing mechanism for adjusting an angle between the first upper and lower swinging bodies is provided near an end of the first upper and lower swinging body opposite to the first hinge portion, and a first engagement member for engaging the second component with a side surface of the first component before insertion into the notch is provided on the opening and closing mechanism, the second component has a second upper and lower rocking body, one end of the second upper and lower rocking body is connected by a second hinge portion so as to be rotatable up and down, and at an end of the second upper and lower rocking body opposite to the second hinge portion, one of the second upper and lower rocking bodies is provided with a second engagement member for engaging the first component, and both of the second upper and lower rocking bodies are provided with a mechanism for releasing the second engagement member from the first engagement member after the cut is enlarged, the second engaging member is a protrusion protruding upward from the second vertical swinging body, the releasing mechanism is a lever provided at the tip of the upper side of the second vertical swinging body, and a lever-type hook member provided at the lower side of the second vertical swinging body, the first engagement member includes a hook receiving member provided on the first vertical swinging body, the upper hook receiving member of the first vertical swinging body has a groove for receiving the protrusion in the direction of the hinge portion, and the lower hook receiving member of the first vertical swinging body has a recess for fitting with the tip of the lever-type hook member, By operating the lever and the lever-type hook member, the second engagement member can be engaged with and disengaged from the first engagement member. Opening device.

2. 2. The dilator according to claim 1, wherein the opening and closing mechanism is composed of a cylindrical body that penetrates the first upper and lower rocking bodies and has a screw thread on its surface, and a rotating member that has a through hole provided in each of the first upper and lower rocking bodies and has a screw groove on its inner surface that fits with the screw thread of the cylindrical body, and has a rotation axis in the lateral direction of the first upper and lower rocking bodies.

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