Posterior cruciate ligament protector

Abstract

The present invention discloses a posterior cruciate ligament protector, which belongs to the technical field of medical devices. The posterior cruciate ligament protector is used for knee joint surgery, including a tube body, the tube body has an axial through hole, a sliding rod is arranged in the axial through hole, a protective piece is arranged at the lower end of the tube body, the protective piece has an arc-shaped groove opening toward the side for accommodating the posterior cruciate ligament, and the tube body and the protective piece are an integrated structure; a cutting piece is arranged at the lower end of the sliding rod, the cutting piece is arranged in the arc-shaped groove, a cutting edge is arranged at the end of the cutting piece, the sliding rod and the cutting piece are an integrated structure, and a push rod is arranged at the upper end of the sliding rod. The present invention is easy to operate and has a good protective effect on the posterior cruciate ligament. As a conventional instrument that meets multiple functions, the present invention can realize the functions of protecting the cruciate ligament during surgery and actively stimulating cutting of the tibial plateau when needed.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, in particular to a posterior cruciate ligament protector used for knee joint surgery. Background Art

[0002] The knee joint is one of the most important joints in the human body. Total knee replacement is the main method for treating severe degenerative arthritis of the knee in the middle and late stages. It has been widely used clinically because it can effectively relieve knee pain and restore joint function and range of motion. The purpose of total knee replacement is to restore normal knee movement, maintain normal knee range of motion and stability, and maintain good proprioception of the knee. The complete preservation of the posterior cruciate ligament during surgery plays a vital role in the stability of the knee joint, the recovery of knee proprioception after surgery, and walking gait.

[0003] In existing total knee replacement surgery, since there is no dedicated surgical instrument or device to protect the posterior cruciate ligament, the position and size of the lower attachment bone block of the posterior cruciate ligament can only be determined by visual inspection or the use of long steel nails, which is not only time-consuming and labor-intensive, but also has poor protection effect on the posterior cruciate ligament. When using an electric oscillating saw blade to perform tibial plateau osteotomy, it is very easy to partially or completely avulse the lower attachment bone block of the tibia side of the posterior cruciate ligament, causing the posterior cruciate ligament to loosen, thereby affecting the postoperative efficacy and the service life of the knee prosthesis, leading to surgical failure. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a posterior cruciate ligament protector which is easy to operate and has good protective effect.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A posterior cruciate ligament protector comprises a tube body, wherein the tube body has an axial through hole, and a sliding rod is arranged in the axial through hole, wherein:

[0007] A protective member is provided at the lower end of the tube body, the protective member having an arc-shaped groove opening toward the side for accommodating the posterior cruciate ligament, and the tube body and the protective member are an integral structure;

[0008] The lower end of the sliding rod is provided with a cutting piece, the cutting piece is arranged in the arc groove, the end of the cutting piece is provided with a cutting edge, the sliding rod and the cutting piece are an integrated structure, and the upper end of the sliding rod is provided with a push rod.

[0009] Furthermore, the protective member includes a straight section and a bent section located below the straight section and bent toward the opening side of the arc groove.

[0010] Furthermore, the tail end of the bending portion is provided with a chamfered structure or a protrusion for positioning, and / or the tail end of the bending portion is provided with a pair of convex wings on both sides of the arc groove.

[0011] Furthermore, the thickness of the arc groove is 1.5-2 mm, and the width is 10-15 mm; the length of the straight section is 20-30 mm, and the length of the bent section is 30-40 mm.

[0012] Furthermore, the cutting piece is arc-shaped and is disposed in the arc-shaped groove.

[0013] Furthermore, the upper end of the sliding rod has an external thread, the lower end of the push rod is provided with a threaded hole, and the sliding rod is connected in the threaded hole.

[0014] Furthermore, a vertical socket is provided at the upper end of the tube body for accommodating the push rod, the vertical socket is coaxial with the axial through hole and the inner diameter of the vertical socket is larger than the inner diameter of the axial through hole so as to form a step surface between the two, and a spring is provided in the vertical socket, the upper end of the spring abuts against the lower end surface of the push rod, and the lower end of the spring abuts against the step surface.

[0015] Furthermore, the push rod is provided with a scale, and / or the upper end of the push rod is provided with a plastic ball.

[0016] Furthermore, the tube body includes a flat cylindrical thick section at the upper part, a cylindrical thin section at the lower part, and a conical transition section between the flat cylindrical thick section and the cylindrical thin section.

[0017] Furthermore, the flat cylindrical thick section is a cylinder that is milled flat at the front and back ends, and cylindrical handles are provided on both sides of the upper end of the flat cylindrical thick section. The end faces of the handles that contact the flat cylindrical thick section are arc-shaped surfaces, and the arc-shaped surfaces include a cylindrical middle section that matches the cylindrical surfaces on the left and right sides of the flat cylindrical thick section and covering side wings that extend to the milled flat surfaces on the front and back sides of the flat cylindrical thick section.

[0018] Furthermore, transverse insertion holes are provided on both sides of the upper end of the flat cylindrical thick section, and the handle is provided with insertion posts that match the transverse insertion holes, and the handle is plugged into the flat cylindrical thick section.

[0019] The present invention has the following beneficial effects:

[0020] The posterior cruciate ligament protector of the present invention has a protective member at the lower end of the tube body with an arc-shaped groove that can accommodate the posterior cruciate ligament, thereby protecting the posterior cruciate ligament; and the cutting member retracted in the arc-shaped groove of the protective member can be extended by pushing the push rod, so that the cutting member is inserted into the tibial bone, thereby protecting the lower stop point of the posterior cruciate ligament. The present invention is easy to operate and has a good protective effect on the posterior cruciate ligament. In addition, when necessary, secondary excitation can be achieved through the connection of the sliding rod without changing the overall structural size of the device, and the tibial platform can be cut with the help of the cutting edge of the cutting member, thereby playing a multi-functional use. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a front structural schematic diagram of the posterior cruciate ligament protector of the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the side structure of the posterior cruciate ligament protector is shown;

[0023] Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure of the posterior cruciate ligament protector is shown;

[0024] Figure 4 for Figure 1 A schematic diagram of the structure of the middle tube body and the protective member;

[0025] Figure 5 for Figure 1 A schematic diagram of the structure of the middle sliding rod and the cutting piece;

[0026] Figure 6 for Figure 1 Schematic diagram of the matching structure of the middle tube body and the handle. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0028] The present invention provides a posterior cruciate ligament protector, such as Figure 1-6 As shown, it includes a tube body 1, the tube body 1 has an axial through hole 10, and a sliding rod 2 is arranged in the axial through hole 10, wherein:

[0029] A protective member 3 is provided at the lower end of the tube body 1. The protective member 3 has an arc-shaped groove 31 which opens toward the side and is used to accommodate the posterior cruciate ligament. The tube body 1 and the protective member 3 are an integral structure.

[0030] The lower end of the sliding rod 2 is provided with a cutting member 4, which is arranged in the arc groove 31. The cutting member 4 can be in various shapes, such as a long strip, etc. In order to make the cutting member 4 better arranged in the arc groove 31 and not affect the protection of the arc groove 31 to the posterior cruciate ligament, the cutting member 4 is preferably an arc (such as Figure 5 As shown) and attached to the arc groove 31, the cutting piece 4 is a thin-walled piece, and its shape is the same as the arc groove 31, which will not hinder the arc groove 31 from protecting the posterior cruciate ligament, and can also maximize the cutting range of the cutting piece 4 and reduce the number of cutting times; a cutting edge 41 is provided at the end of the cutting piece 4, the sliding rod 2 and the cutting piece 4 are an integrated structure, and a push rod 5 is provided at the upper end of the sliding rod 2.

[0031] It is understandable that the tube body 1, the sliding rod 2, the protective member 3 and the cutting member 4 can all be made of metal materials, such as stainless steel.

[0032] When in use, first use the push rod 5 to drive the sliding rod 2 and the cutting piece 4 to move upward, so that the cutting piece 4 is completely retracted into the arc groove 31 of the protective piece 3 at the lower end of the tube body 1, and then the tibia is exposed during the operation. The protector is held above the tibia so that the arc groove 31 of the protective piece 3 is aligned with the posterior cruciate ligament to play a protective role, and then the tibial platform is osteotomized. When the oscillating saw blade osteotomizes to the point where it contacts the protective piece 3, it cannot continue to move forward, thereby protecting the lower end point of the posterior cruciate ligament (the oscillating saw is swung in a horizontal position, specifically 10 mm below the articular surface). In order to protect the bone below the posterior cruciate ligament, it is necessary to use the cutting edge 41 at the end of the cutting piece 4 to align with the part of the bone on the tibia connected to the posterior cruciate ligament (i.e., the front side of the lower end point of the posterior cruciate ligament), push the push rod 5 to make the cutting piece 4 inserted into the tibial bone to a suitable depth, and then perform manual resection to prevent the oscillating saw from damaging the bone.

[0033] The posterior cruciate ligament protector of the present invention has a protective member at the lower end of the tube body with an arc-shaped groove that can accommodate the posterior cruciate ligament, thereby protecting the posterior cruciate ligament; and the cutting member retracted in the arc-shaped groove of the protective member can be extended by pushing the push rod, so that the cutting member is inserted into the tibial bone, thereby protecting the lower stop point of the posterior cruciate ligament. The present invention is easy to operate and has a good protective effect on the posterior cruciate ligament. In addition, when necessary, secondary excitation can be achieved through the connection of the sliding rod without changing the overall structural size of the device, and the tibial platform can be cut with the help of the cutting edge of the cutting member, thereby playing a multi-functional use.

[0034] Considering that the lower end point of the posterior cruciate ligament of the tibia may be blocked by the femur during surgery, for ease of use, the lower end of the protective member 3 is preferably bent toward the opening side of the arc groove 31 (at Figure 2-3In the embodiment shown, it is bent to the right), that is, the protective member 3 may include a straight section 32 and a bent section 33 located below the straight section 32 and bent toward the opening side of the arc groove 31, so as to better adapt to the trochlear groove of the femur, thereby facilitating the accurate insertion of the protector into the required position of the tibia.

[0035] Furthermore, the tail end of the bending portion 33 may be provided with a chamfered structure or a spur for positioning, so as to facilitate the positioning and maintenance of the protective member 3 at the desired position of the tibia. Preferably, the tail end of the bending portion 33 adopts a chamfered structure, which can not only achieve the positioning effect and prevent the position movement of the instrument, but also effectively reduce the possibility of the positioning structure causing unnecessary damage to the surrounding tissue structures. The tail end of the bending portion 33 may also be provided with a pair of convex wings 34 on both sides of the arc groove 31. The convex wings 34 can be integrally extended from both sides of the arc groove 31. The purpose of the convex wings 34 is to form a larger arc structure at the tail end than the rest of the bending portion 33. In order to better accommodate the posterior cruciate ligament, the curvature of the bending portion 33 should not be too large. With the help of the convex wings 34, a larger arc structure can be formed, thereby better wrapping the cutting edge 41.

[0036] To better meet the needs of use, optionally, the thickness of the arc groove 31 can be 1.5-2mm (for example, 1.8mm), and the width can be 10-15mm (for example, 13mm); the length of the straight section 32 can be 20-30mm (for example, 25mm), and the length of the bent section 33 can be 30-40mm (for example, 34mm).

[0037] like Figure 3 and Figure 5 As shown, the connection between the sliding rod 2 and the push rod 5 can be specifically: the upper end of the sliding rod 2 has an external thread 21, the lower end of the push rod 5 is provided with a threaded hole, the sliding rod 2 is connected in the threaded hole, and the threaded connection is convenient for disassembly, cleaning and disinfection.

[0038] like Figure 3 As shown, the upper end of the tube body 1 can be provided with a vertical socket 14 for accommodating the push rod 5, which can guide the movement of the push rod 5 to avoid axial shaking; the vertical socket 14 is coaxial with the axial through hole 10 and the inner diameter of the vertical socket 14 is larger than the inner diameter of the axial through hole 10, so that a step surface 17 is formed between the two. A spring 15 is provided in the vertical socket 14, and the upper end of the spring 15 abuts against the lower end surface of the push rod 5, and the lower end of the spring 15 abuts against the step surface 17. In this way, the cutting member 4 can be automatically retracted into the arc groove 31 of the protective member 3 to prevent the cutting member 4 from being thrown out due to gravity and other effects, causing undesirable cutting. By reasonably selecting the size of the vertical socket 14 and the spring 15, the up and down movement range of the cutting member 4 can be limited. The up and down movement range of the cutting member 4 is preferably designed to be 10mm, which can meet the cutting needs of the tibial plateau during surgery. By adjusting the threaded connection depth between the sliding rod 2 and the push rod 5, the up and down movement range of the cutting member 4 can be flexibly changed / adjusted.

[0039] In order to facilitate identification of the moving distance of the sliding rod 2 and thus know the depth of the cutting edge 41 of the cutting member 4 inserted into the tibia, a scale may be provided on the push rod 5. In order to facilitate operation of the push rod 5, a ball 6 may be provided at the upper end of the push rod 5. The material of the ball 6 may be stainless steel or plastic. When the push rod 5 is moved by knocking the ball 6, the noise during the knocking process can be reduced.

[0040] like Figure 4 As shown, the outer shape of the tube body 1 preferably includes a flat cylindrical thick section 11 at the top, a cylindrical thin section 13 at the bottom, and a conical transition section 12 between the flat cylindrical thick section 11 and the cylindrical thin section 13, so that the upper part of the tube body 1 is larger in size for easy gripping, and the lower part is smaller in size to avoid interfering with the surgical field of view.

[0041] Specifically, the flat cylindrical thick section 11 can be a cylindrical shape that is milled flat at the front and back. A cylindrical handle 7 can be provided on both sides of the upper end of the flat cylindrical thick section 11. The end surface of the handle 7 that contacts the flat cylindrical thick section 11 is an arc surface 110. Figure 6 As shown, the arc surface 110 includes a cylindrical middle section 1101 that matches the cylindrical surfaces on the left and right sides of the flat cylindrical thick section 11 and a covering side wing 1102 that extends to the milled flat surfaces on the front and rear sides of the flat cylindrical thick section 11. This structure can significantly improve the firmness of the handle 7 and the tube body 1 after they are installed together, and is also considered by doctors to have the best hand feel after clinical data collection. Further, as Figure 4 As shown, transverse insertion holes 16 can be provided on both sides of the upper end of the flat cylindrical thick section 11, and the handle 7 is provided with a plug post (not shown) that matches the transverse insertion hole 16. The handle 7 is plugged into the flat cylindrical thick section 11, and an interference fit can be adopted, and external welding can also be used to further improve the firmness of the connection.

[0042] In summary, the present invention is a conventional instrument that meets multiple functions. It can protect the cruciate ligament during surgery and actively stimulate the cutting of the tibial platform when needed; it is easy to operate and has a good protective effect on the posterior cruciate ligament; the whole is detachable, which is convenient for cleaning and disinfection.

[0043] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A posterior cruciate ligament protector, characterized in that: It comprises a tube body, the tube body has an axial through hole, a sliding rod is arranged in the axial through hole, wherein: A protective member is provided at the lower end of the tube body, the protective member having an arc-shaped groove opening toward the side for accommodating the posterior cruciate ligament, and the tube body and the protective member are an integral structure; A cutting piece is provided at the lower end of the sliding rod, the cutting piece is arranged in the arc groove, a cutting edge is provided at the end of the cutting piece, the sliding rod and the cutting piece are an integrated structure, and a push rod is provided at the upper end of the sliding rod; The protection member comprises a straight section and a bent section located below the straight section and bent toward the opening side of the arc-shaped groove. The cutting member is arc-shaped and is attached to the arc-shaped groove.

2. The posterior cruciate ligament protector according to claim 1, characterized in that: The tail end of the bending portion is provided with a chamfered structure or a spur for positioning, and / or the tail end of the bending portion is provided with a pair of convex wings on both sides of the arc groove.

3. The posterior cruciate ligament protector according to claim 1, characterized in that: The thickness of the arc groove is 1.5-2 mm, and the width is 10-15 mm; the length of the straight section is 20-30 mm, and the length of the bent section is 30-40 mm.

4. The posterior cruciate ligament protector according to claim 1, characterized in that: The upper end of the sliding rod has an external thread, and the lower end of the push rod is provided with a threaded hole, and the sliding rod is connected to the threaded hole; the upper end of the tube body is provided with a vertical socket for accommodating the push rod, the vertical socket is coaxial with the axial through hole and the inner diameter of the vertical socket is larger than the inner diameter of the axial through hole so as to form a step surface between the two, and a spring is provided in the vertical socket, the upper end of the spring abuts against the lower end surface of the push rod, and the lower end of the spring abuts against the step surface.

5. The posterior cruciate ligament protector according to claim 4, characterized in that: The push rod is provided with scales, and / or the upper end of the push rod is provided with a plastic ball.

6. The posterior cruciate ligament protector according to any one of claims 1 to 5, characterized in that: The tube body comprises a flat cylindrical thick section at the upper part, a cylindrical thin section at the lower part, and a conical transition section between the flat cylindrical thick section and the cylindrical thin section.

7. The posterior cruciate ligament protector according to claim 6, characterized in that: The flat cylindrical thick section is a cylinder that is flattened at the front and back ends. Cylindrical handles are provided on both sides of the upper end of the flat cylindrical thick section. The end faces of the handles that contact the flat cylindrical thick section are arc-shaped surfaces. The arc-shaped surfaces include a cylindrical middle section that matches the cylindrical surfaces on the left and right sides of the flat cylindrical thick section and covering side wings that extend to the milled flat surfaces on the front and back sides of the flat cylindrical thick section.

8. The posterior cruciate ligament protector according to claim 7, characterized in that: Both sides of the upper end of the flat cylindrical thick section are provided with transverse insertion holes, and the handle is provided with insertion columns matched with the transverse insertion holes, and the handle is inserted into the flat cylindrical thick section.

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