Customized assembly type prosthesis for limb defects

Abstract

The utility model discloses a customized assembly type prosthesis for limb defects, and relates to the technical field of 3D printing medical instruments. The problem that in the prior art, a prosthesis is prone to torsion under the condition that four limbs are stressed, and consequently the prosthesis is broken or loses efficacy is solved. Comprising a femoral intramedullary handle and a tibia intramedullary handle, the femoral intramedullary handle and the tibia intramedullary handle are respectively provided with an inserting part and a bearing part which are matched with each other, the inserting part is a cylindrical boss, a plurality of ribs are uniformly arranged on the outer wall of the boss along the axis direction of the boss, the bearing part is a mounting hole matched with the boss, and the outer wall of the bearing part is provided with a through hole matched with the boss. Grooves matched with the corresponding protruding edges are formed in the inner wall of the mounting hole in the axis direction of the mounting hole, and the protruding edges correspond to the grooves in a one-to-one mode. The customized assembly type prosthesis for the limb defects is simple in structure and convenient to assemble, the protruding edges are inserted into the corresponding grooves in a matched mode, and the situation that the prosthesis is in relative rotation torsion failure under the condition that the limbs are stressed is effectively prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of 3D printing medical devices, in particular to a customized modular prosthesis for limb defects. Background Art

[0002] The repair of bone defects caused by trauma, tumors, infections, etc. is a common and difficult problem in clinical practice. Allogeneic bone and autologous vascularized bone tissue are currently the most commonly used methods for bone defect repair. The advantage of allogeneic bone is that it can provide bone mass and early support, but it takes a long time to activate, has a low healing rate with the recipient, and is prone to infection. The advantage of autologous vascularized bone is that it is a living bone transplant, has a high healing rate, and has a certain anti-infection ability, but the shape of the autologous bone cannot match the bone defect area. A prosthesis that completely matches the bone defect area needs to be formed for support, and then the autologous bone tissue is filled into the prosthesis, which can greatly promote bone tissue growth and shorten the healing time. Traditional processing technology is usually used to make standard orthopedic prostheses, and most prostheses are solid structures with poor biological activity and stress shielding effects.

[0003] 3D printing technology is a digital technology that has developed rapidly in recent years. Based on model data, it is formed layer by layer to ultimately produce processed parts for use in various fields. Its personalization and high degree of design freedom have led to the widespread application of 3D printing technology in the field of orthopedics. In particular, for patients with large bone defects, customized modular prostheses can be made to fill the defect area while preserving the patient's joint tissue as much as possible. However, current prostheses have stability issues. Modular prostheses are prone to twisting when the limbs are stressed, causing the prosthesis to break or fail. Revision and replacement of broken or failed prostheses can cause secondary damage to the patient. Utility Model Content

[0004] In order to solve the above problems, the present invention provides a customized modular prosthesis for limb defects, which effectively prevents the prosthesis from failing due to relative rotation and torsional stress when the limbs are subjected to stress.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] The utility model discloses a customized modular prosthesis for limb defects, including a femoral intramedullary stem and a tibial intramedullary stem, wherein the femoral intramedullary stem and the tibial intramedullary stem are respectively provided with a plug-in portion and a receiving portion that cooperate with each other, the plug-in portion is a columnar boss, and the outer wall of the boss is evenly provided with a plurality of ridges along its axial direction, the receiving portion is a mounting hole that cooperates with the boss, and the inner wall of the mounting hole is provided with a groove that cooperates with the corresponding ridges along its axial direction, and the ridges and grooves correspond to each other one by one.

[0007] Furthermore, the length of the ridge is 30mm-35mm.

[0008] Furthermore, the cross-sectional shape of the ridge is a sawtooth shape, and the cross-sectional shape of the groove is a V-shape that matches the ridge with the sawtooth shape.

[0009] Furthermore, the bottom width of the sawtooth-shaped ridge is 2mm-4mm, and the height of the sawtooth-shaped ridge is 2mm-4mm.

[0010] Furthermore, the turning corners of the top and bottom of the sawtooth-shaped ridges are chamfered.

[0011] Furthermore, the femoral intramedullary stem and the mounting end of the patient's femur are provided with relative fixing plates, and both the femoral intramedullary stem and the fixing plate are provided with matching screw holes, screws are passed through the screw holes, and the fixing plate and the femoral intramedullary stem are integrally formed.

[0012] Furthermore, the fixing plate is a spiral structure.

[0013] Furthermore, the femoral intramedullary stem is a hollow structural component, and the femoral intramedullary stem is a porous structural component.

[0014] Furthermore, the length of the femoral intramedullary stem is 20mm-40mm, and the thickness of the femoral intramedullary stem is 2mm-4mm.

[0015] Furthermore, the shape of the tibial intramedullary stem is cylindrical, the diameter of the tibial intramedullary stem is 8mm-25mm, and the length of the tibial intramedullary stem is 80mm-120mm.

[0016] The beneficial effects of the present invention are as follows: the custom modular prosthesis for limb defects of the present application is completed by plugging and assembling the femoral intramedullary stem and the tibial intramedullary stem, which is convenient for targeted replacement in the later stage. Only the failed intramedullary stem part needs to be replaced, thereby reducing the harm caused to the patient. The femoral intramedullary stem and the tibial intramedullary stem are plugged and assembled, with a simple structure and easy assembly. The ridges are plugged into the corresponding grooves, which effectively prevents the prosthesis from relative rotational torsional failure when the limbs are stressed, thereby increasing the service life of the prosthesis and reducing the number of prosthesis replacements, thereby reducing the harm caused to the patient and the replacement cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a schematic structural diagram of a customized modular prosthesis for limb defects provided by an embodiment of the present invention and installed on the patient's femur;

[0019] Figure 2 This is a schematic structural diagram of the femoral intramedullary stem provided by an embodiment of the present utility model;

[0020] Figure 3 This is a schematic structural diagram of the tibial intramedullary stem provided by an embodiment of the present utility model;

[0021] Figure 4 It is a cross-sectional schematic diagram showing that the inserting portion of the femoral intramedullary stem provided by an embodiment of the present invention is inserted into the receiving portion of the tibial intramedullary stem.

[0022] Reference numerals: patient's femur 1 , fixation plate 2 , femoral intramedullary stem 3 , tibial intramedullary stem 4 , plug-in portion 5 , receiving portion 6 . DETAILED DESCRIPTION

[0023] To make the purpose, technical solution, and advantages of the present invention more clear, the technical solution of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] like Figure 1 、 Figure 2 、 Figure 3 、 Figure 4As shown, the utility model is a customized modular prosthesis for limb defects, including a femoral intramedullary stem 3 and a tibial intramedullary stem 4, wherein the femoral intramedullary stem 3 and the tibial intramedullary stem 4 are respectively provided with a plug-in portion 5 and a receiving portion 6 that cooperate with each other, the plug-in portion 5 is a columnar boss, the outer wall of the boss is evenly provided with a plurality of ridges along its axial direction, the receiving portion 6 is a mounting hole that is plugged into and cooperates with the boss, and the inner wall of the mounting hole is provided with grooves that cooperate with the corresponding ridges along its axial direction, and the ridges and grooves correspond one to one. Among them, the femoral intramedullary stem 3 and the tibial intramedullary stem 4 are respectively provided with a plug-in portion 5 and a receiving portion 6 that cooperate with each other, such as the plug-in portion 5 is provided at the lower end of the femoral intramedullary stem 3, and the receiving portion 6 that is plugged into and cooperates with the plug-in portion 5 is provided at the upper end of the tibial intramedullary stem 4. When the intramedullary stem 3 and the tibial intramedullary stem 4 are connected, the plug-in portion 5 is plugged into the receiving portion 6. First, the patient's femur and tibia are scanned, and then the femoral intramedullary stem 3 and tibial intramedullary stem 4 models are established based on the scan data. Then, the femoral intramedullary stem 3 and tibial intramedullary stem 4 are 3D printed using the equipment, and the femoral intramedullary stem 3 is installed in the femoral part and the tibial intramedullary stem 4 is installed in the tibial part.

[0026] A customized modular prosthesis for limb defects based on the above structure is completed by plugging and assembling the femoral intramedullary stem 3 and the tibial intramedullary stem 4, which is convenient for targeted replacement at a later stage. Only the failed intramedullary stem part needs to be replaced, thereby reducing the harm caused to the patient. The femoral intramedullary stem 3 and the tibial intramedullary stem 4 are plugged and assembled, with a simple structure and easy assembly. The ridges are plugged into the corresponding grooves, effectively preventing the prosthesis from failing due to relative rotation and torsional force when the limbs are stressed, thereby increasing the service life of the prosthesis and reducing the number of prosthesis replacements, thereby reducing the harm caused to the patient and the replacement cost.

[0027] Among them, Figure 2 As shown, the length of the ridge is 30mm-35mm, and is designed to match the patient's corresponding bone marrow cavity length, diameter, cross-sectional shape and other factors.

[0028] Preferably, Figure 2 、 Figure 3 、 Figure 4 As shown, the cross-sectional shape of the ridge is a sawtooth shape, and the cross-sectional shape of the groove is a V shape that matches the ridge with a sawtooth shape.

[0029] The contact area between the V-shaped ridges and grooves is larger, and the force-bearing capacity is stronger, which can better prevent the prosthesis from failing due to relative rotation and torsional stress when the limbs are under stress.

[0030] The bottom width of the sawtooth-shaped ridge is 2 mm to 4 mm, and the height of the sawtooth-shaped ridge is 2 mm to 4 mm.

[0031] Preferably, the turning corners of the top and bottom of the sawtooth-shaped ridges are chamfered with arcs.

[0032] In order to avoid stress concentration points, the turning corners of the top and bottom of the serrated ridges are chamfered to increase their resistance to deformation, reduce the risk of failure, and improve their stability.

[0033] Preferably, the femoral intramedullary stem 3 and the mounting end of the patient's femur 1 are provided with a relative fixing plate 2, and the femoral intramedullary stem 3 and the fixing plate 2 are both provided with matching screw holes, and the screw holes are passed through the screw holes, and the fixing plate 2 and the femoral intramedullary stem 3 are integrally formed.

[0034] The fixation plate 2 and the femoral intramedullary stem 3 are integrally formed, which avoids installing the fixation plate 2 after the prosthesis is installed, reduces the installation steps of the external fixation plate 2, improves the overall performance, and is more stable and reliable.

[0035] Preferably, the fixing plate 2 is a spiral structure.

[0036] The spiral structure of the fixing plate 2 is better wrapped around the patient's femur 1, increasing the area of ​​close fit with the patient's femur 1, which is conducive to uniform force transmission.

[0037] Preferably, Figure 1 、 Figure 2 As shown, the femoral intramedullary stem 3 is a hollow structural component, and the femoral intramedullary stem 3 is a porous structural component.

[0038] The femoral intramedullary stem 3 is a hollow structural component with a cavity. A plurality of through holes are evenly arranged in the femoral intramedullary stem 3, and the through holes are connected to the cavity. The through holes are evenly distributed throughout the femoral intramedullary stem 3, forming a hollow femoral intramedullary stem 3, which can promote the growth of the patient's femur 1 into the through holes, so that the patient's femur 1 and the femoral intramedullary stem 3 are tightly combined, thereby enhancing the bonding strength between the femoral intramedullary stem 3 and the patient's femur 1.

[0039] The length of the femoral intramedullary stem 3 is 20 mm to 40 mm, and the thickness of the femoral intramedullary stem 3 is 2 mm to 4 mm. The matching design is performed based on factors such as the length, diameter, and cross-sectional shape of the patient's corresponding medullary cavity.

[0040] The shape of the tibial intramedullary stem 4 is cylindrical, the diameter of the tibial intramedullary stem 4 is 8mm-25mm, and the length of the tibial intramedullary stem 4 is 80mm-120mm. It is designed to match the patient's corresponding bone cavity length, diameter and cross-sectional shape, etc., to retain the patient's own bone tissue, especially bone joints, as much as possible, reduce surgical trauma, and shorten the patient's recovery time.

[0041] The above is only a specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A custom modular prosthesis for limb defects, comprising a femoral intramedullary stem (3) and a tibial intramedullary stem (4), characterized in that: The femoral intramedullary stem (3) and the tibial intramedullary stem (4) are respectively provided with a plug-in portion (5) and a receiving portion (6) that cooperate with each other, the plug-in portion (5) is a columnar boss, the outer wall of the boss is evenly provided with a plurality of ridges along its axial direction, the receiving portion (6) is a mounting hole that cooperates with the boss, the inner wall of the mounting hole is provided with a groove that cooperates with the corresponding ridge along its axial direction, and the ridges and grooves correspond to each other.

2. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The length of the ridge is 30mm-35mm.

3. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The cross-sectional shape of the ridge is a sawtooth shape, and the cross-sectional shape of the groove is a V shape that matches the ridge with the sawtooth shape.

4. The custom modular prosthesis for limb defects according to claim 3, characterized in that: The bottom width of the sawtooth-shaped ridge is 2mm-4mm, and the height of the sawtooth-shaped ridge is 2mm-4mm.

5. The custom modular prosthesis for limb defects according to claim 3, characterized in that: The turning corners of the top and bottom of the sawtooth-shaped ridge are chamfered.

6. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The femoral intramedullary stem (3) and the mounting end of the patient's femur (1) are provided with a relative fixing plate (2), and the femoral intramedullary stem (3) and the fixing plate (2) are both provided with matching screw holes, screws are passed through the screw holes, and the fixing plate (2) and the femoral intramedullary stem (3) are integrally formed.

7. The custom modular prosthesis for limb defects according to claim 6, characterized in that: The fixing plate (2) is a spiral structure.

8. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The femoral intramedullary stem (3) is a hollow structural component, and the femoral intramedullary stem (3) is a porous structural component.

9. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The length of the femoral intramedullary stem (3) is 20 mm to 40 mm, and the thickness of the femoral intramedullary stem (3) is 2 mm to 4 mm.

10. The custom modular prosthesis for limb defects according to claim 1, characterized in that: The shape of the tibial intramedullary stem (4) is cylindrical, the diameter of the tibial intramedullary stem (4) is 8mm-25mm, and the length of the tibial intramedullary stem (4) is 80mm-120mm.

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