Nested assembly internal fixation device for the lateral tibial plateau

Abstract

The present invention discloses a nested assembly type internal fixation device for the outer side of the tibial plateau, comprising a titanium alloy steel plate, a proximal absorbable module and a top pressure reduction locking absorbable rod, a window top pressure reduction area corresponding to the collapsed area of ​​the tibial plateau articular surface is provided on the titanium alloy steel plate close to the lateral bone surface of the tibia, a steel plate proximal locking hole is provided on the proximal side of the window top pressure reduction area, and a steel plate sliding pressurizing hole is provided on the distal side; a proximal absorbable module is embedded and installed in the window top pressure reduction area, an absorbable polylactic acid ring is embedded in the proximal module micro-motion hole on the proximal absorbable module, the top pressure reduction locking absorbable rod is driven into the collapsed area of ​​the tibial plateau articular surface through the proximal module micro-motion hole, and the tail of the top pressure reduction locking absorbable rod is threadedly connected with the absorbable polylactic acid ring, so as to realize micro-motion connection and lock the proximal absorbable module to maintain top pressure reduction. The internal fixation device of the present invention is patient-friendly, can be customized, is convenient for window top pressure reduction of the articular surface and effectively maintains fixation.

Description

Technical Field

[0001] The invention belongs to the technical field of orthopedic medical instruments, in particular to a nested assembly type internal fixation device used for the outer side of a tibial plateau. Background Art

[0002] In the treatment of tibial plateau fractures, the anatomical locking plate on the outside of the tibial plateau plays an important role in the stability and healing of the fracture site. Traditional internal fixation devices are mostly made of titanium alloy materials, such as steel plates and screws. Although they have certain effects, they have problems such as platform collapse again, stress shielding, and loose fixation. For example, if the stiffness of metal materials is too high, it is easy to cause stress shielding and affect fracture healing; and during the fracture healing process, the stiffness of the internal fixation device changes, and the constant mechanical properties of the metal material may cause bending, fracture, etc., resulting in fixation failure; the compatibility of metal materials with human tissues is relatively poor, which is easy to cause adverse reactions such as allergies and rejection; at the same time, because metal materials are not easy to degrade in the body, traditional internal fixation devices need to be removed by secondary surgery after fracture healing, which brings certain pain and economic burden to patients. In addition, since traditional internal fixation devices are mostly static fixations, they are difficult to adapt to the physiological and mechanical environment of the fracture site, resulting in unstable fixation effects at the fracture site, which are prone to displacement, dislocation and other phenomena, affecting fracture healing; since the fixation effect of traditional internal fixation devices is unstable, patients need a longer recovery period and undergo multiple review and adjustments, which not only increases the patient's pain and economic burden, but may also affect the treatment effect.

[0003] With the development of materials science, polylactic acid, as a degradable material, has good biocompatibility and degradability and is widely used in the field of medical devices. The application of polylactic acid materials in fracture internal fixation devices can provide good support in the early stage of fracture healing process, and then gradually degrade and fuse with the surrounding bone to reduce local tissue irritation. Biological fixation technology emphasizes the biological environment of fracture treatment, reduces mechanical interference to the fracture site, and promotes the natural healing process of fractures. However, due to the insufficient material strength of polylactic acid steel plates, polylactic acid steel plates are currently only suitable for non-weight-bearing areas, and polylactic acid steel plates require regular shapes. When the area around the joint is complex and irregular, pure polylactic acid material structures cannot be used.

[0004] In this context, nested assembly and micro-motion internal fixation technology came into being. This technology can better adapt to the physiological environment of the fracture site and promote fracture healing by personalized nested assembly of internal fixation devices and retaining a certain amount of micro-motion during the fixation process. In addition, with the continuous advancement of medical device manufacturing technology, the design and manufacture of internal fixation devices are also gradually developing. Personalized, precise, and functional design concepts have gradually become the development trend in the field of technology. Improvements and innovations in existing technologies can not only improve the treatment effect, but also reduce the pain and economic burden of patients.

[0005] Therefore, for tibial plateau fractures with complex irregular shapes around the knee joint side, a new internal fixation solution for tibial plateau fractures needs to be provided. Summary of the invention

[0006] The purpose of the present invention is to provide a nested assembly type internal fixation device for the lateral side of the tibial plateau in view of the problems existing in the prior art.

[0007] The purpose of the present invention is to be solved by the following technical solutions:

[0008] A nested assembly type internal fixation device for the outer side of a tibial plateau, characterized in that the internal fixation device comprises a titanium alloy steel plate designed based on the anatomical morphology of the outer side of the tibial plateau, a proximal absorbable module and a top pressure reduction and locking absorbable rod, the titanium alloy steel plate being able to be closely attached to the outer bone surface of the tibia, a window top pressure reduction area corresponding to the collapsed area of ​​the articular surface of the tibial plateau is provided on the titanium alloy steel plate, a steel plate proximal locking hole is provided on the proximal side of the window top pressure reduction area, and a steel plate sliding pressurizing hole is provided on the distal side; a proximal absorbable module is embedded and installed in the window top pressure reduction area, an absorbable polylactic acid ring is embedded in the proximal module micro-motion hole on the proximal absorbable module, the top pressure reduction and locking absorbable rod is driven into the collapsed area of ​​the articular surface of the tibial plateau through the proximal module micro-motion hole, and the tail of the top pressure reduction and locking absorbable rod is threadedly connected to the absorbable polylactic acid ring, so as to achieve micro-motion connection and lock the proximal absorbable module to maintain top pressure reduction.

[0009] The proximal outer edge of the proximal absorbable module is provided with an open proximal module absorbable groove, and an open steel plate proximal absorption groove is provided on the titanium alloy steel plate on the proximal side of the window top pressure reduction area. The open proximal module absorbable groove and the steel plate proximal absorption groove arranged opposite to each other constitute a proximal absorbable hole, and the proximal absorbable hole with an embedded absorbable polylactic acid ring is used for implanting absorbable screws and / or titanium alloy screws.

[0010] The proximal absorption groove of the steel plate is a 3 / 4 groove, and the proximal absorption groove of the module is a 1 / 4 groove.

[0011] A proximal module locking hole is provided on the distal side of the proximal absorbable module, and the proximal module locking hole with an absorbable polylactic acid ring or a titanium alloy spring ring embedded therein is used for implanting a top pressure reduction locking absorbable rod or an absorbable screw or a titanium alloy locking screw; the proximal module micro-motion holes are arranged in pairs, and the proximal module micro-motion holes and the proximal module locking holes form an inverted triangle layout.

[0012] When the proximal absorbable module needs to be pressurized to maintain top pressure reduction, a titanium alloy locking screw is implanted in the locking hole of the proximal module embedded with a titanium alloy spring ring.

[0013] The titanium alloy locking screw can be sleeved with a hollow absorbable support rod.

[0014] A plurality of proximal Kirschner wire holes are arranged beside the proximal module micro-motion hole, and the proximal Kirschner wire holes are used to temporarily fix the proximal absorbable module in the window top pressure reduction area.

[0015] Generally, two proximal Kirschner wire holes are arranged between the proximal module micro-motion hole and the proximal module locking hole, and the proximal Kirschner wire holes are located at the shoulder of the proximal module locking hole.

[0016] The width of the proximal absorbable module is 12 mm to 32 mm, and the edge width of the titanium alloy steel plates on both sides of the proximal absorbable module is 3 mm to 4 mm.

[0017] The top pressure resetting and locking absorbable rod is composed of a titanium alloy tail absorbable screw and a hollow absorbable support rod with a hexagonal cross-section structure. The hollow absorbable support rod is sleeved in the absorbable body of the titanium alloy tail absorbable screw and the titanium alloy tail absorbable screw passes through the hollow absorbable support rod.

[0018] The implantation angle of the top-pressure reduction locking absorbable rod is 45° to 75° to achieve the best top-pressure reduction effect.

[0019] The proximal locking hole of the steel plate and the sliding pressurizing hole of the steel plate can be respectively implanted with titanium alloy screws for fixing the titanium alloy steel plate; the sliding pressurizing hole of the steel plate is a U-shaped groove structure, so that the titanium alloy screw at the sliding pressurizing hole of the steel plate can adjust the position.

[0020] A number of proximal articular surface Kirschner wire holes are arranged on the proximal outer edge of the titanium alloy steel plate. The proximal articular surface Kirschner wire holes opening outward are used to implant proximal articular surface Kirschner wires. The proximal articular surface Kirschner wires are used to temporarily position the titanium alloy steel plate and guide the titanium alloy screws implanted at the proximal locking holes of the steel plate; spare Kirschner wire holes are respectively provided on the titanium alloy steel plate on the proximal and distal sides of the window top pressure reduction area, and a spare Kirschner wire hole is provided on the distal tail of the titanium alloy steel plate.

[0021] The Kirschner wire hole near the joint surface is a 3 / 4 hole.

[0022] The distal end of the titanium alloy steel plate is provided with a strip-shaped distal locking area of ​​the steel plate, and the distal side of the distal locking area of ​​the steel plate is connected to the sliding pressurizing hole of the steel plate; the distal locking area of ​​the steel plate is used to embed a distal absorbable module with a distal module locking hole, and the distal module locking hole on the proximal side of the distal absorbable module opens toward the sliding pressurizing hole of the steel plate, and titanium alloy screws and / or absorbable screws are implanted at the distal module locking hole, or absorbable screws and / or titanium alloy screws are implanted in the distal module locking hole with an absorbable polylactic acid ring or a titanium alloy spring ring embedded therein, so as to position and fix the distal absorbable module in the distal locking area of ​​the steel plate; the edge width of the titanium alloy steel plate on both sides of the proximal end of the distal locking area of ​​the steel plate is 1mm to 2mm, and the edge width of the titanium alloy steel plate on both sides of the distal end is less than 1mm, so that the distal locking area of ​​the steel plate on the titanium alloy steel plate presents a strip-shaped groove that gradually expands from the proximal end to the distal end.

[0023] The proximal absorbable module, the distal absorbable module, the absorbable polylactic acid ring, the absorbable screw, the absorbable body of the titanium alloy tail absorbable screw, and the hollow absorbable support rod are all made of polylactic acid absorbable material.

[0024] In the above scheme, the proximal end of the tibia is near the knee joint, and one end of the titanium alloy steel plate near the knee joint is defined as the proximal end of the titanium alloy steel plate, and the other end of the titanium alloy steel plate is defined as the distal end of the titanium alloy steel plate. All "proximal sides" involved in the technical scheme refer to the side relatively close to the knee joint, and "distal sides" refer to the side relatively far away from the knee joint.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] The nested assembly internal fixation device for the outer side of the tibial plateau provided by the present invention is developed based on the latest progress in the fields of polylactic acid materials, titanium alloy materials, biological fixation technology, and nested assembly and micro-motion internal fixation technology. The internal fixation device is made of polylactic acid and titanium alloy composite materials, has good biocompatibility and mechanical properties, and the components based on anatomical design can be personalized, precise, and functionalized, and can better adapt to the morphology of the tibial plateau, improve the stability of fixation and the treatment effect, and in a good biomechanical environment and with a strong support structure, moderate joint rehabilitation training can be performed in the early stage to reduce the loss of joint function; the nested assembly and micro-motion internal fixation structure adopted by the internal fixation device can gradually degrade during the fracture healing process, reducing the burden on patients; in addition, the design of the internal fixation device is simple and easy to use, and has better structural support to avoid the re-collapse of the tibial plateau.

[0027] The proximal absorbable module of the nested assembly internal fixation device for the outer side of the tibial plateau provided by the present invention is nested in the frame of the titanium alloy steel plate, and the lower part of the proximal absorbable module is the fracture window opening top pressure reduction area. The top pressure reduction locking absorbable rod equipped with a hexagonal hollow absorbable support rod combined with the absorbable polylactic acid ring can fix the fracture collapse site to the greatest extent and has a universal locking function; the polylactic acid degradable material can grow permeably and tightly fuse with the callus, thereby avoiding the re-collapse after the titanium alloy steel plate is removed, thereby improving the stability of the treatment.

[0028] The nested integral micro-motion structure adopted by the nested assembled internal fixation device for the outer side of the tibial plateau provided by the present invention has high rigidity in the early stage of fracture healing. As the fracture heals, the micro-motion of the fracture ends gradually disappears, and the micro-motion structure gradually produces micro-motion as the local absorbable material degrades, which can promote fracture healing. After the fracture heals, the presence of the micro-motion can reduce the stress shielding of the internal fixation plate and reduce the secondary surgery to remove the plate; the absorbable polylactic acid material is mainly distributed in the low stress area of ​​the device. Due to the presence of the nested micro-motion structure, fracture healing can be promoted. As the polylactic acid material is completely absorbed, the device can be regarded as an internal fixation bracket structure to reduce complications.

[0029] The nested assembly type internal fixation device for the outer side of the tibial plateau provided by the present invention compounds the polylactic acid absorbable material on the titanium alloy locking steel plate, thereby reducing the use of metal materials. The absorbable material is added to the local components of the locking structure to improve the stress of the internal fixation steel plate during the fracture healing stage as the degradable materials in different composite parts are absorbed, thereby providing a biological fixation steel plate that is more in line with the mechanical environment of fracture healing. Appropriately adding part of the absorbable polylactic acid material to the bone defect has an osteoinductive effect, and the local composite polylactic acid absorbable components and absorbable screws effectively avoid joint damage made of metal materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Attached Figure 1 A schematic diagram of the main structure of the nested assembly type internal fixation device for the lateral side of the tibial plateau provided by the present invention;

[0031] Attached Figure 2 A schematic diagram of the combined structure of the titanium alloy steel plate and the titanium alloy spring ring provided by the present invention;

[0032] Attached Figure 3 A schematic diagram of the structure of the proximal absorbable module provided by the present invention;

[0033] Attached Figure 4 A schematic diagram of the structure of the distal absorbable module provided by the present invention;

[0034] Attached Figure 5 A schematic diagram of the structure of the top-pressing, resetting and locking absorbable rod provided by the present invention;

[0035] Attached Figure 6 A schematic diagram of the structure of the titanium alloy tail absorbable screw provided by the present invention;

[0036] Attached Figure 7 A schematic diagram of the structure of the hollow absorbable support rod provided by the present invention;

[0037] Attached Figure 8 A schematic diagram of the combined structure of the titanium alloy steel plate, the distal absorbable module, the proximal absorbable module and the implanted top pressure resetting and locking absorbable rod provided by the present invention;

[0038] Attached Fig. 9 A schematic diagram of the structure of the absorbable polylactic acid ring provided by the present invention;

[0039] Attached Fig.10 A schematic diagram of the structure of a titanium alloy spring ring provided by the present invention;

[0040] Attached Fig.11 The present invention provides Figure 1 Schematic diagram of the structure mounted on the tibial platform;

[0041] Attached Fig.12 A perspective view of the nested assembly type internal fixation device for the lateral side of the tibial plateau provided by the present invention in use.

[0042] Among them: 1—titanium alloy steel plate; 11—Kirschner wire hole at proximal joint surface; 12—proximal locking hole of steel plate; 13—proximal absorption groove of steel plate; 14—window top pressure reduction area; 15—steel plate sliding pressure hole; 16—distal locking area of ​​steel plate; 17—spare Kirschner wire hole; 2—proximal absorbable module; 21—proximal module absorbable groove; 22—proximal module micro-motion hole; 23—proximal module locking hole; 24—proximal Kirschner wire hole; 25—proximal absorbable hole; 3—distal absorbable module; 31—distal module locking hole; 32—distal Kirschner wire hole; 4—titanium alloy screw; 5—titanium alloy spring ring; 6—titanium alloy locking screw; 7—absorbable polylactic acid ring; 8—absorbable screw; 9—top pressure reduction locking absorbable rod; 91—titanium alloy tail absorbable screw; 92—hollow absorbable support rod. DETAILED DESCRIPTION

[0043] In order to explain the technical content, structural features, objectives and effects of the invention in detail, the technical solutions in the embodiments of the present invention will be described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0044] In the present invention, spatial orientation terms such as "horizontal", "vertical", "front", "rear", "left", "right", "top", "on", "inside", "one side", etc. are used to describe the positional relationship, orientation or movement direction of components as shown in the accompanying drawings. This is only for the convenience of describing the present invention, and does not imply or indicate that the referred device or component must have a specific orientation or be constructed or operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium; "fixation" can be a full fixation in all directions, or it can be fixed in a certain direction so that the component cannot be offset or displaced in that direction, but can be moved in other directions.

[0046] like Figure 1-12 As shown: a nested assembly type internal fixation device for the lateral side of the tibial plateau, the internal fixation device comprises a titanium alloy steel plate 1 designed based on the anatomical morphology of the lateral side of the tibial plateau, a proximal absorbable module 2 and a top pressure reduction locking absorbable rod 9, the titanium alloy steel plate 1 can be closely attached to the lateral bone surface of the tibia, a window top pressure reduction area 14 corresponding to the collapsed area of ​​the tibial plateau articular surface is provided on the titanium alloy steel plate 1, a steel plate proximal locking hole 12 is provided on the proximal side of the window top pressure reduction area 14, and a steel plate sliding pressurizing hole 15 is provided on the distal side, the steel plate proximal locking hole 12 and the steel plate sliding pressurizing hole 15 can be respectively A titanium alloy screw 4 is implanted to fix the titanium alloy steel plate 1; a proximal absorbable module 2 is embedded and installed in the window opening top pressure reduction area 14, and an absorbable polylactic acid ring 7 is embedded in the proximal module micro-motion hole 22 on the proximal absorbable module 2; a top pressure reduction and locking absorbable rod 9 is driven into the collapsed area of ​​the tibial plateau articular surface through the proximal module micro-motion hole 22, and the tail of the top pressure reduction and locking absorbable rod 9 is threadedly connected with the absorbable polylactic acid ring 7, so as to realize the micro-motion connection and lock the proximal absorbable module 2 to maintain the top pressure reduction; the implantation angle of the top pressure reduction and locking absorbable rod 9 is 45° to 75° to achieve the best top pressure reduction effect.

[0047] In the above structure, a plurality of proximal articular surface Kirschner wire holes 11 are arranged on the proximal outer edge of the titanium alloy steel plate 1. The proximal articular surface Kirschner wire holes 11 opening outward are used for implanting proximal articular surface Kirschner wires. The proximal articular surface Kirschner wires are used to temporarily position the titanium alloy steel plate 1 and guide the titanium alloy screws 4 implanted at the proximal locking holes 12 of the steel plate. Spare Kirschner wire holes 17 are respectively provided on the titanium alloy steel plate 1 on the proximal and distal sides of the window opening top pressure reduction area 14, and a spare Kirschner wire hole 17 is provided at the distal tail of the titanium alloy steel plate 1. The spare Kirschner wire holes 17 are only used to position the titanium alloy steel plate 1 with spare Kirschner wires when surgery requires.

[0048] In the above structure, the window top pressure reset zone 14 where the proximal absorbable module 2 is located is located in the central area in the width direction of the titanium alloy steel plate 1, the width of the proximal absorbable module 2 is 12mm~32mm, and the edge width of the titanium alloy steel plate 1 on both sides of the proximal absorbable module 2 is 3mm~4mm, so that the window top pressure reset zone 14 is as large as possible, and the volume of the proximal absorbable module 2 is expanded; an open proximal module absorbable groove 21 is provided on the proximal outer edge of the proximal absorbable module 2, and the titanium alloy on the proximal side of the window top pressure reset zone 14 is provided. An open proximal absorption groove 13 of the steel plate is provided on the steel plate 1, and the proximal module absorbable groove 21 and the proximal absorption groove 13 of the steel plate that are arranged opposite to each other constitute a proximal absorbable hole 25, and the proximal absorbable hole 25 with an embedded absorbable polylactic acid ring 7 is used to implant an absorbable screw 8 and / or a titanium alloy screw 4; a proximal module locking hole 23 is provided on the distal side of the proximal absorbable module 2, and the proximal module locking hole 23 with an embedded absorbable polylactic acid ring 7 or a titanium alloy spring ring 5 is used to implant a top pressure reduction locking absorbable rod 9 or an absorbable screw 8 or a titanium alloy locking screw 6. The proximal module micro-motion holes 22 are arranged in pairs and the proximal module micro-motion holes 22 and the proximal module locking holes 23 form a stable inverted triangle layout structure. The preferred solution is that the proximal module micro-motion holes 22 and the proximal module locking holes 23 with embedded absorbable polylactic acid rings 7 are both implanted with top pressure reset locking absorbable rods 9; but when it is necessary to apply pressure to the proximal absorbable module 2 to maintain top pressure reset, the proximal module locking hole 23 with embedded titanium alloy spring rings 5 ​​is implanted with a titanium alloy locking screw 6, and a hollow absorbable support rod 92 can be sleeved on the titanium alloy locking screw 6 as needed.

[0049] In order to temporarily fix the proximal absorbable module 2, a plurality of proximal Kirschner wire holes 24 are arranged beside the proximal module micro-motion hole 22. The proximal Kirschner wire holes 24 are used to temporarily fix the proximal absorbable module 2 in the window top pressure reduction area 14. Generally, two proximal Kirschner wire holes 24 are arranged between the proximal module micro-motion hole 22 and the proximal module locking hole 23, and the proximal Kirschner wire holes 24 are located at the shoulder of the proximal module locking hole 23.

[0050] In the above structure, the top pressure resetting and locking absorbable rod 9 is composed of a titanium alloy tail absorbable screw 91 and a hollow absorbable support rod 92 with a hexagonal cross-sectional structure. The hollow absorbable support rod 92 is sleeved on the absorbable body of the titanium alloy tail absorbable screw 91 and the titanium alloy tail absorbable screw 91 passes through the hollow absorbable support rod 92.

[0051] In the above structure, the steel plate sliding pressurizing hole 15 is a U-shaped groove structure, so that the titanium alloy screw 4 at the steel plate sliding pressurizing hole 15 can adjust the position.

[0052] In the above structure, a strip-shaped steel plate distal locking area 16 is provided at the distal end of the titanium alloy steel plate 1, and the distal side of the steel plate distal locking area 16 is connected to the steel plate sliding pressurizing hole 15; the steel plate distal locking area 16 is used to embed a distal absorbable module 3 with a distal module locking hole 31, and the distal module locking hole 31 on the proximal side of the distal absorbable module 3 opens toward the steel plate sliding pressurizing hole 15, and a titanium alloy screw 4 and / or an absorbable screw 8 is implanted at the distal module locking hole 31, or an absorbable screw 8 and / or a titanium alloy screw 4 is implanted in the distal module locking hole 31 with an embedded absorbable polylactic acid ring 7 or a titanium alloy spring ring 5, so as to position and fix the distal absorbable module 3 in the steel plate distal locking area 16. Since the proximal end of the nested assembly type internal fixation device is a low stress area, the absorbable component can be larger as it moves toward the distal end, so the edge width of the titanium alloy steel plate 1 on both sides of the proximal end of the distal locking area 16 of the steel plate is 1mm to 2mm, and the edge width of the titanium alloy steel plate 1 on both sides of the distal end is less than 1mm, so that the distal locking area 16 of the titanium alloy steel plate 1 presents a strip-shaped groove that gradually expands from the proximal end to the distal end, which can maintain the overall integrity of the structure of the titanium alloy steel plate 1. In addition, a distal Kirschner wire hole 32 can also be set on the distal absorbable module 3 as needed.

[0053] The specific structure of a nested assembly type internal fixation device for the lateral side of the tibial plateau provided by the present invention is demonstrated below through specific embodiments.

[0054] like Figure 1-2, 11-12 are nested assembly internal fixation devices for the lateral side of the tibial plateau, with one end of the titanium alloy steel plate adjacent to the knee joint being the proximal end of the titanium alloy steel plate, and the other end of the titanium alloy steel plate being the distal end of the titanium alloy steel plate. From the proximal end to the distal end of the titanium alloy steel plate 1, four 3 / 4-hole proximal articular surface Kirschner wire holes 11, three proximal locking holes 12 of the steel plate, four proximal absorption grooves 13 of the steel plate (opening toward the window top pressure reduction area 14), a window top pressure reduction area 14 (substantially connected to the four proximal absorption grooves 13 of the steel plate), a steel plate sliding pressure hole 15, a steel plate distal locking area 16, and three spare Kirschner wire holes 17 (located on the titanium alloy steel plate 1) are arranged in sequence on the titanium alloy steel plate 1. The proximal articular surface Kirschner wire holes 11 opened outward are used to implant proximal articular surface Kirschner wires to temporarily fix the titanium alloy plate 1, so that the nested assembly internal fixation device can be as close to the tibial articular surface as possible. The proximal articular surface Kirschner wires implanted in the proximal articular surface Kirschner wire holes 11 have a positioning and guiding function, which can better control the reduction and fixation of the fracture. It is a special design that facilitates the opening of windows and the top pressure reduction of the articular surface and can effectively maintain the fixation; the proximal locking holes 12 of the plate are used to implant titanium alloy screws 4 for fixing the titanium alloy plate 1. A row of three titanium alloy screws 4 can provide more support and can be used for early weight-bearing. The proximal absorbable groove 13 of the steel plate and the absorbable groove 21 of the proximal module are combined to form a proximal absorbable hole 25, and the proximal absorbable hole 25 is used to implant an absorbable screw 8 and / or a titanium alloy screw 4 with an absorbable polylactic acid ring 7, preferably an absorbable screw 8, and the absorbable polylactic acid ring 7 and the absorbable screw 8 constitute a micro-motion structure relative to the proximal absorbable module 2 and the titanium alloy steel plate 1; the window top pressure reduction area 14 is used to embed the proximal absorbable module 2, and the proximal absorbable module 2 is fixed with a micro-motion structure composed of an absorbable polylactic acid ring 7 and a top pressure reduction locking absorbable rod 9, or further configured with a micro-motion structure composed of an absorbable polylactic acid ring 7 and a top pressure reduction locking absorbable rod 9 combined with a titanium alloy spring ring 5 (or an absorbable polylactic acid ring 7) and a titanium alloy locking screw 6 (or a combined structure of a titanium alloy locking screw 6 and a hollow absorbable support rod 92); the plate sliding pressurization hole 15 is used to implant a titanium alloy screw 4 for fixing the titanium alloy plate 1, and the position of the titanium alloy screw 4 can be adjusted; the distal locking area 16 of the plate is used to embed the distal absorbable module 3 and the distal absorbable module 3 is fixed with an absorbable screw 8 and / or a titanium alloy screw 4, and the distal absorbable module 3 can also be fixed with a micro-motion structure composed of an absorbable polylactic acid ring 7 and an absorbable screw 8; the spare Kirschner wire hole 17 is used to temporarily implant a Kirschner wire to fix the titanium alloy plate 1, and the temporarily implanted Kirschner wire should be removed after the installation of the nested assembly internal fixation device is completed.

[0055] like Figure 1 , 3 , 11, and 12, the proximal absorbable module 2 is sequentially arranged with four open proximal module absorbable grooves 21, two proximal module micro-motion holes 22, a proximal module locking hole 23, and two proximal Kirschner wire holes 24 from the proximal end to the distal end of the titanium alloy steel plate 1. The relatively arranged proximal module absorbable grooves 21 and the proximal absorbable grooves 13 of the steel plate constitute a proximal absorbable hole 25 into which an absorbable screw 8 with an absorbable polylactic acid ring 7 can be implanted. The micro-motion structure formed by the absorbable screw 8 with the absorbable polylactic acid ring 7 can avoid the collapse again after the internal fixation is removed in the second operation. At the same time, the absorbable polylactic acid ring 7 and the absorbable screw 8 have an osteoinductive effect. The two internal The proximal module micro-motion holes 22 embedded with the absorbable polylactic acid ring 7 are respectively implanted with the top pressure reduction and locking absorbable rod 9, and the tail of the top pressure reduction and locking absorbable rod 9 is threadedly connected with the absorbable polylactic acid ring 7, so as to realize the micro-motion connection and lock the proximal absorbable module 2 to maintain the top pressure reduction; the proximal module locking hole 23 embedded with the absorbable polylactic acid ring 7 or the titanium alloy spring ring 5 is used to implant the top pressure reduction and locking absorbable rod 9 or the absorbable screw 8 or the titanium alloy locking screw 6. When the proximal absorbable module 2 needs to be moderately pressurized, the proximal module locking hole 23 embedded with the titanium alloy spring ring 5 is implanted with the titanium alloy locking screw 6; the proximal Kirschner wire hole 24 is used to temporarily lock the proximal absorbable module 2 in the windowed top pressure reduction area 14.

[0056] like Figure 4 , 11 , the distal absorbable module 3 shown in 12 is provided with five distal module locking holes 31, wherein the opening of the distal module locking hole 31 located at the distal end of the distal absorbable module 3 faces the steel plate sliding pressurizing hole 15, and titanium alloy screws 4 and / or absorbable screws 8 are implanted in the distal module locking hole 31, or absorbable screws 8 and / or titanium alloy screws 4 are implanted in the distal module locking hole 31, or absorbable screws 8 and / or titanium alloy screws 4 are implanted in the distal module locking hole 31 embedded with an absorbable polylactic acid ring 7 or a titanium alloy spring ring 5, preferably absorbable screws 8 are implanted, so as to position and fix the distal absorbable module 3 in the distal locking area 16 of the steel plate.

[0057] like Figure 5 , 6 , 7, 8, 11, 12 shown in the top pressure reset locking absorbable rod 9, Figure 5 The top pressure reset locking absorbable rod 9 shown is composed of Figure 6 The titanium alloy tail absorbable screw 91, Figure 7The hollow absorbable support rod 92 shown in the figure is composed of a combination of a titanium alloy tail absorbable screw 91 composed of a screw-shaped absorbable body and a titanium alloy tail, and the absorbable body is made of polylactic acid material; the hollow absorbable support rod 92 made of polylactic acid material adopts a hexagonal cross-sectional structure; the hollow absorbable support rod 92 is sleeved on the absorbable body of the titanium alloy tail absorbable screw 91 and the titanium alloy tail absorbable screw 91 passes through the hollow absorbable support rod 92, and the installation structure of the top pressure reset locking absorbable rod 9 is as shown in Figure 8 , 11 As shown in , 12 , the top pressure resetting and locking absorbable rod 9 can be used as an osteoinductive component, and the micro-motion structure based on the top pressure resetting and locking absorbable rod 9 is also beneficial to rehabilitation.

[0058] like Fig. 9 , 11 , and the partially open absorbable polylactic acid ring 7 shown in 12 has a thread inside the ring. The absorbable polylactic acid ring 7 can be correspondingly embedded in the proximal module micro-motion hole 22, the proximal module locking hole 23, the proximal absorbable hole 25, and the distal module locking hole 31. The titanium alloy screw 4, the titanium alloy locking screw 6, the absorbable screw 8, and the top pressure reduction locking absorbable rod 9 that are compatible with the absorbable polylactic acid ring 7 can all constitute a micro-motion connection structure. The design of the micro-motion structure enables the fracture to have higher rigidity in the early stage of healing. As the fracture heals, the micro-motion of the fracture ends gradually disappears.

[0059] like Fig.10 , 11 , and 12 show a partially open titanium alloy spring ring 5, wherein the titanium alloy spring ring 5 has a thread inside the ring, and the titanium alloy spring ring 5 is embedded in the locking hole 23 of the proximal module. The titanium alloy locking screw 6 implanted through the locking hole 23 of the proximal module, or the titanium alloy locking screw 6 sleeved on the hollow absorbable support rod 92, or the top pressure resetting locking absorbable rod 9 can pressurize the proximal absorbable module 2, and can form a micro-motion structure relative to the proximal absorbable module 2 to realize the micro-motion connection of the proximal absorbable module 2. The design of the micro-motion structure enables the fracture to have higher rigidity in the early stage of healing. As the fracture heals, the micro-motion of the fracture end gradually disappears.

[0060] In the above structure, the design of the nested overall micro-motion structure enables the fracture to have higher stiffness in the early stage of healing. During the healing process, the micro-motion structure gradually produces micro-motion as the local absorbable material degrades, which can promote fracture healing in the later stage of fracture healing. As the fracture heals, the micro-motion of the fracture ends gradually disappears.

[0061] The following further explains the nested assembly internal fixation device for the lateral side of the tibial plateau provided by the present invention from eight aspects, including the special structure based on anatomical design, material selection, avoiding locking nails from entering the knee joint, stress change and fracture healing, osteogenic induction, avoiding damage to the knee joint by metal materials, modular design, and universal locking function.

[0062] 1. Special structure of anatomical design: The internal fixation device adopts anatomical design to better adapt to the shape of the tibial plateau, improve the stability of fixation and the treatment effect; the proximal articular surface Kirschner wire is used in combination with the 3 / 4 hole proximal articular surface Kirschner wire hole 11 for temporary fixation. This temporary fixation design helps to accurately reduce and fix the fracture site, and is convenient for maintaining fixation when opening the window and pressing the top to reduce the articular surface; multiple rows of screws can provide more support to ensure the stability of the internal fixation device; at the same time, the structural design of micro-motion connection and nested assembly can adjust the fixation strength and micro-motion according to the different stages of fracture healing to promote fracture healing and reduce stress shielding effect.

[0063] 2. Material selection: The internal fixation device is made of a composite of titanium alloy and polylactic acid absorbable material. Titanium alloy has good biocompatibility and strength, while polylactic acid absorbable material can gradually degrade during the fracture healing process over time, thereby reducing the problem of secondary surgery for removal and alleviating the burden on patients.

[0064] 3. Prevent locking nails from entering the knee joint: The internal fixation device uses a proximal articular surface Kirschner wire in conjunction with a 3 / 4 hole proximal articular surface Kirschner wire hole 11 to position and guide the titanium alloy screw 4 in the subchondral bone, which can effectively prevent the titanium alloy screw 4 implanted in the proximal locking hole 12 of the steel plate from being driven into the knee joint, thereby reducing further damage to the knee joint; and the titanium alloy screw 4 positioned and guided in the subchondral bone can accurately fix the fracture collapse area, thereby improving the treatment effect.

[0065] 4. Stress change and fracture healing: Due to the absorption of polylactic acid absorbable material in different composite parts, the stress of titanium alloy steel plate 1 will change during the fracture healing stage. The design of this composite structure is more in line with the mechanical environment of fracture healing; it allows patients to walk with weight at an early stage and reduce the patient's recovery time; in addition, with the complete absorption of the polylactic acid material, the internal fixation device can be regarded as an internal fixation bracket structure to further reduce complications.

[0066] 5. Osteogenesis induction effect: Adding some absorbable polylactic acid material to the bone defect has an osteogenic induction effect (the combination of absorbable polylactic acid ring 7 and absorbable screw 8, the combination of absorbable polylactic acid ring 7 and top pressure reduction locking absorbable rod 9, the combination of absorbable polylactic acid ring 7 and hexagonal hollow absorbable support rod 92 and absorbable screw 8, the combination of absorbable polylactic acid ring 7 and hexagonal hollow absorbable support rod 92 and titanium alloy screw 4, the combination of absorbable polylactic acid ring 7 and hexagonal hollow absorbable support rod 92 and titanium alloy locking screw 6, etc.), which helps the healing of the fracture site and reduces complications.

[0067] 6. Avoiding damage to joints caused by metal materials: By using absorbable components such as the proximal absorbable module 2, the distal absorbable module 3, the absorbable polylactic acid ring 7, the absorbable screw 8, the absorbable body of the titanium alloy tail absorbable screw 91, and the hollow absorbable support rod 92, further damage to the joints caused by metal materials can be effectively avoided.

[0068] 7. Modular design: The distal end of the titanium alloy steel plate 1 adopts a nested design of distal absorbable modules 3, and the proximal end adopts a nested design of proximal absorbable modules 2. This modular design makes the implant more flexible and also helps to reduce damage to surrounding tissues.

[0069] 8. Universal locking function: The combination of the absorbable polylactic acid ring 7 and the top pressure reduction locking absorbable rod 9, or the absorbable polylactic acid ring 7 and the titanium alloy locking screw 6 sleeved with the hollow absorbable support rod 92 has a universal locking function, which can fix the fracture collapse site to the greatest extent.

[0070] When the nested assembly type internal fixation device for the outer side of the tibial plateau provided by the present invention is used, the structural bone blocks of the tibial plateau fracture are firstly aligned and reset, and the joint surface is initially reset. After the reset, the bone cortex of the fracture end is kept relatively stable, and the absorbable polylactic acid ring 7 is embedded in the distal module locking hole 31 of the distal absorbable module 3 and placed in the distal locking area 16 of the titanium alloy steel plate 1. The partially assembled titanium alloy steel plate 1 is placed in a suitable position close to the bone surface, and 2-3 proximal articular surface Kirschner wire holes 11 are implanted close to the articular surface to fix the titanium alloy steel plate 1. Temporary fixation, the implanted length of the Kirschner wire near the articular surface shall not exceed half the length of the transverse diameter of the lateral tibial plateau; the perspective is close to the articular surface and the central collapse is appropriately pried and reduced. The Kirschner wire near the articular surface is used as a parallel reference. A short titanium alloy screw 4 (parallel and close to the articular surface) is implanted in the proximal locking hole 12 of the steel plate to fix the titanium alloy steel plate 1. After appropriate adjustment, a titanium alloy screw 4 is implanted in the sliding pressure hole 15 of the steel plate; the titanium alloy spring ring 5 is embedded in the proximal module locking hole 23 of the proximal absorbable module 2 and is not installed temporarily. A window is opened and pressed in the window opening and pressure reduction area 14 first. The collapsed area of ​​the tibial plateau articular surface is repositioned and filled with cancellous bone and / or allogeneic bone in the collapsed area. Three absorbable screws 8 with absorbable polylactic acid rings 7 are then implanted in the proximal absorption groove 13 of the titanium alloy steel plate 1 to maintain the subchondral bone reduction of the articular surface. The proximal absorbable module 2 with the titanium alloy spring ring 5 is then loaded so that the proximal absorption groove 13 of the steel plate and the proximal module absorbable groove 21 can be combined to form a proximal absorbable hole 25. Two Kirschner wires are used to temporarily fix the proximal absorbable hole 25 through the proximal Kirschner wire hole 24 (two at the proximal module locking hole 23). Absorbable module 2, drill holes with an electric drill to measure the approximate length, select two top-pressure reset locking absorbable rods 9 of appropriate length and implant them into the micro-motion hole 22 of the proximal module embedded with absorbable polylactic acid ring 7, and the tail of the top-pressure reset locking absorbable rod 9 is threadedly connected with the absorbable polylactic acid ring 7 to achieve micro-motion connection and lock the proximal absorbable module 2 to maintain top-pressure reset; then implant a titanium alloy locking screw 6 with a hollow absorbable support rod 92 in the proximal module locking hole 23; finally, use an absorbable screw 8 of appropriate length to implant it into the distal module locking hole of the distal absorbable module 3. After completion, remove the proximal joint surface Kirschner wire implanted in the proximal joint surface Kirschner wire hole 11 and the Kirschner wire implanted in the proximal Kirschner wire hole 24.

[0071] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention; any technology not involved in the present invention can be realized by existing technologies.

Claims

1. A nested assembly type internal fixation device for the lateral side of the tibial plateau, characterized in that: The internal fixation device comprises a titanium alloy steel plate (1) designed based on the anatomical shape of the outer side of the tibial plateau, a proximal absorbable module (2) and a top pressure reduction locking absorbable rod (9), wherein the titanium alloy steel plate (1) can be closely attached to the outer side bone surface of the tibia, a window top pressure reduction area (14) corresponding to the collapsed area of ​​the tibial plateau articular surface is provided on the titanium alloy steel plate (1), a steel plate proximal locking hole (12) is provided on the proximal side of the window top pressure reduction area (14), and a steel plate sliding pressure hole (12) is provided on the distal side. 5); a proximal absorbable module (2) is embedded and installed in the window top pressure reduction area (14); an absorbable polylactic acid ring (7) is embedded in the proximal module micro-motion hole (22) on the proximal absorbable module (2); a top pressure reduction and locking absorbable rod (9) is inserted into the collapsed area of ​​the tibial plateau articular surface through the proximal module micro-motion hole (22); and the tail of the top pressure reduction and locking absorbable rod (9) is threadedly connected to the absorbable polylactic acid ring (7), so as to achieve micro-motion connection and lock the proximal absorbable module (2) to maintain top pressure reduction; The proximal outer edge of the proximal absorbable module (2) is provided with an open proximal module absorbable groove (21), and an open steel plate proximal absorbable groove (13) is provided on the titanium alloy steel plate (1) on the proximal side of the window top pressure reduction area (14). The proximal module absorbable groove (21) and the steel plate proximal absorbable groove (13) that are arranged opposite to each other constitute a proximal absorbable hole (25), and the proximal absorbable hole (25) with an absorbable polylactic acid ring (7) embedded therein is used for implanting an absorbable screw (8) and / or a titanium alloy screw (4); A proximal module locking hole (23) is provided on the distal side of the proximal absorbable module (2); the proximal module locking hole (23) embedded with an absorbable polylactic acid ring (7) or a titanium alloy spring ring (5) is used for implanting a top-pressure resetting locking absorbable rod (9) or an absorbable screw (8) or a titanium alloy locking screw (6); the proximal module micro-motion holes (22) are arranged in pairs, and the proximal module micro-motion holes (22) and the proximal module locking holes (23) form an inverted triangle layout.

2. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1, characterized in that: A plurality of proximal Kirschner wire holes (24) are arranged beside the proximal module micro-motion hole (22), and the proximal Kirschner wire holes (24) are used to temporarily fix the proximal absorbable module (2) in the window top pressure reduction area (14).

3. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1, characterized in that: The width of the proximal absorbable module (2) is 12 mm to 32 mm, and the edge widths of the titanium alloy steel plates (1) on both sides of the proximal absorbable module (2) are 3 mm to 4 mm.

4. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1, characterized in that: The top-pressure resetting and locking absorbable rod (9) is composed of a titanium alloy tail absorbable screw (91) and a hollow absorbable support rod (92) with a hexagonal cross-sectional structure; the hollow absorbable support rod (92) is sleeved on the absorbable body of the titanium alloy tail absorbable screw (91), and the titanium alloy tail absorbable screw (91) passes through the hollow absorbable support rod (92).

5. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1 or 4, characterized in that: The implantation angle of the top-pressure reduction locking absorbable rod (9) is 45° to 75°, so as to achieve the best top-pressure reduction effect.

6. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1, characterized in that: The proximal locking hole (12) of the steel plate and the sliding pressurizing hole (15) of the steel plate can respectively be implanted with a titanium alloy screw (4) for fixing the titanium alloy steel plate (1); the sliding pressurizing hole (15) of the steel plate is a U-shaped groove structure, so that the position of the titanium alloy screw (4) at the sliding pressurizing hole (15) of the steel plate can be adjusted.

7. The nested assembly type internal fixation device for the lateral side of the tibial plateau according to claim 1 or 6, characterized in that: The proximal outer edge of the titanium alloy steel plate (1) is provided with a plurality of proximal articular surface Kirschner wire holes (11), and the proximal articular surface Kirschner wire holes (11) opening outward are used for implanting proximal articular surface Kirschner wires, which are used for temporarily positioning the titanium alloy steel plate (1) and guiding the titanium alloy screws (4) implanted at the proximal locking holes (12) of the steel plate; spare Kirschner wire holes (17) are respectively provided on the titanium alloy steel plate (1) at the proximal and distal sides of the window top pressure reduction area (14), and spare Kirschner wire holes (17) are provided at the distal tail of the titanium alloy steel plate (1).

8. The nested assembly internal fixation device for the lateral side of the tibial plateau according to any one of claims 1 and 6, characterized in that: The distal end of the titanium alloy steel plate (1) is provided with a strip-shaped steel plate distal locking area (16), and the distal side of the steel plate distal locking area (16) is connected to the steel plate sliding pressurizing hole (15); the steel plate distal locking area (16) is used to embed a distal absorbable module (3) with a distal module locking hole (31), and the distal module locking hole (31) on the proximal side of the distal absorbable module (3) opens toward the steel plate sliding pressurizing hole (15), and the titanium alloy screw (4) and / or absorbable screw (8) or an absorbable screw (8) is implanted in the distal module locking hole (31). An absorbable screw (8) and / or a titanium alloy screw (4) is implanted in the distal module locking hole (31) of the polylactic acid ring (7) or the titanium alloy spring ring (5) to position and fix the distal absorbable module (3) in the distal locking area (16) of the steel plate; the edge width of the titanium alloy steel plate (1) on both sides of the proximal end of the distal locking area (16) of the steel plate is 1 mm to 2 mm, and the edge width of the titanium alloy steel plate (1) on both sides of the distal end is less than 1 mm, so that the distal locking area (16) of the steel plate on the titanium alloy steel plate (1) presents a strip-shaped groove that gradually expands from the proximal end to the distal end.

Images