CN118902699A - Wrist joint prosthesis - Google Patents

Abstract

The present application provides a wrist joint prosthesis, including a prosthesis body, a medullary needle and a biological fixation device. The prosthesis body is fixed on one end of the radius near the metacarpal bone, and the two ends of the prosthesis body are respectively a first end and a second end, the first end is located at one end near the metacarpal bone, and the second end is located at one end near the elbow joint; the medullary needle is fixedly connected to the end face of the second end, and the medullary needle is used to insert into the radial medullary cavity to fix the prosthesis body on the radius; the biological fixation device is fixedly installed on the end face of the first end, and the biological fixation device can provide different biological fixation interfaces. In the wrist joint prosthesis provided by the embodiment of the present application, the medullary needle fixes the prosthesis body to the radius, and the biological fixation device can provide different biological fixation interfaces according to the specific conditions of the patient, without the need to transplant bones elsewhere, thereby improving the adaptability of the wrist joint prosthesis and avoiding the disadvantages of dislocation, non-union, rejection or causing new trauma in the prior art.

Description

Wrist joint prosthesis

Technical Field

The present invention relates to the technical field of medical devices, and in particular to a wrist joint prosthesis.

Background Art

In the treatment of giant cell tumors and malignant tumors of the distal radius, surgical resection of large sections of tumor bone is the main method. After the tumor bone of the patient's affected part is removed, the patient's affected part needs to be reconstructed to restore the patient's healthy function. The existing reconstruction plans are:

(1) Autologous fibula transplantation, disadvantages: causing new injuries and even affecting the lower limb movement provided by the fibula; in addition, the proximal end of the fibula does not match the wrist joint and often dislocates; it cannot restore the daily function of the wrist joint; the transplanted fibula does not heal with the extreme residual radius.

(2) Allogeneic bone transplantation: Disadvantages: rejection, non-union, and joint mismatch.

(3) Ilium bone transplantation and wrist fusion. Disadvantages: causing new injuries, even affecting the skin sensation of the lateral thigh on the ilium side, loss of mobility after wrist fusion, limited ilium length, and non-union.

(4) Prosthesis replacement of distal radial tumors. Disadvantages: prone to joint dislocation and failure of intramedullary fixation, leading to loosening of the radial fixation end.

Summary of the invention

In view of this, an object of the present invention is to overcome the deficiencies in the prior art and provide a wrist joint prosthesis.

The present invention provides the following technical solutions:

The embodiment of the present application provides a wrist joint prosthesis, including a prosthesis body, a medullary needle and a biological fixation device. The prosthesis body is fixed on the radius near the metacarpal bone, and the two ends of the prosthesis body are respectively a first end and a second end, the first end is located at the end near the metacarpal bone, and the second end is located at the end near the elbow joint; the medullary needle is fixedly connected to the end surface of the second end, and the medullary needle is used to be inserted into the radial medullary cavity to fix the prosthesis body on the radius; the biological fixation device is fixedly installed on the end surface of the first end, and the biological fixation device can provide different biological fixation interfaces.

In one embodiment, the biological fixing member includes a first fixing block and a second fixing block which are separately arranged, the first fixing block has a first biological fixing interface, the second fixing block has a second biological fixing interface, and the first fixing block or the second fixing block is fixedly mounted on the first end.

In one embodiment, the first fixing block is a solid block made of polyethylene material.

In one embodiment, the second fixing block is a block structure having a hollow porous structure.

In one embodiment, a fixing through hole is provided on one end of the prosthesis body close to the first end portion.

In one embodiment, there are more than one fixing through hole.

In one embodiment, the wrist joint prosthesis further comprises a fixing plate, wherein the fixing plate is fixedly connected to the second end portion, and the fixing plate is arranged parallel to the medullary pin with a space therebetween.

In one embodiment, the wrist joint prosthesis also includes a first fixing screw, a first mounting hole is provided on the fixing plate, one end of the first fixing screw is threadedly engaged with the first mounting hole, and the other end of the first fixing screw is fixedly mounted on the radius; a plurality of first mounting holes are provided, and a plurality of first fixing screws are correspondingly provided, wherein at least two of the first fixing screws are used to limit the rotation and movement of the fixing plate, and at least one of the first fixing screws is used to make the fixing plate tightly abut against the radius.

In one embodiment, the wrist joint prosthesis also includes a second fixing screw, and a long mounting hole is provided on the fixing plate, and the long mounting hole is a keyway-type through hole. One end of the second fixing screw can be installed at different positions of the long mounting hole, and the other end of the second fixing screw is fixedly mounted on the radius.

In one embodiment, the wrist joint prosthesis further comprises a connecting plate, a fixing cable and a buckle. The connecting plate has two ends, and the two ends are respectively a first fixing end and a second fixing end, the first fixing end is located at one side of the prosthesis body, and the second fixing end is located at one side of the radius; at least two fixing cables are provided, at least one of which is used to bind the first fixing end and the prosthesis body, and at least one of which is used to bind and fix the second end and the radius; the buckle is used to fix the two ends of the fixing cable to prevent the fixing cable from loosening.

The embodiments of the present invention have the following advantages:

In the wrist joint prosthesis provided in the embodiment of the present application, the medullary pin fixes the prosthesis body to the radius, and the prosthesis body provides an installation basis for the biological fixation device and the medullary pin. The biological fixation device can provide different biological fixation interfaces according to the specific conditions of the patient, without the need to transplant bones elsewhere, thereby improving the adaptability of the wrist joint prosthesis and avoiding the disadvantages of dislocation, non-union, rejection or causing new trauma in the prior art.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

FIG1 is a schematic structural diagram of one embodiment of a wrist joint prosthesis provided by an embodiment of the present application from one viewing angle;

FIG2 is a schematic structural diagram of one embodiment of a wrist joint prosthesis provided by an embodiment of the present application from two viewing angles;

FIG3 is a schematic structural diagram of three perspectives of one embodiment of a wrist joint prosthesis provided by an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a wrist joint prosthesis according to an embodiment of the present application from four perspectives.

Description of main component symbols:

100 - prosthesis body; 110 - fixing through hole; 120 - first end; 130 - second end;

200-biological fixation parts;

300-medullar needle;

400-fixing plate; 410-first fixing screw; 420-installing long hole;

500-radius; 600-ulna; 700-fixing cable; 750-connecting plate.

DETAILED DESCRIPTION

Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of the template are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and/or" used herein includes any and all combinations of one or more of the related listed items.

As shown in Figures 1 to 4, an embodiment of the present application provides a wrist joint prosthesis. Figure 1 shows an application scenario of the wrist joint prosthesis provided by an embodiment of the present application. The wrist joint prosthesis is installed on the radius 500, and there is an ulna 600 next to the radius 500. Relative to the upper and lower positions of the drawing, the metacarpal bone (not shown in the figure) is located above the radius 500 and the ulna 600, and the elbow joint (not shown in the figure) is located below the radius 500 and the ulna 600. The resection site of the tumor bone of the patient's radius 500 is located at one end of the radius 500 close to the metacarpal bone, that is, the upper end of the radius 500 is surgically removed, and the resection of the radius 500 forms an end face, and the wrist joint prosthesis is installed at this end face, and the end face of the prosthesis body 100 of the wrist joint prosthesis abuts against the end face of the resection of the radius 500. FIG. 2 can be regarded as a side view of FIG. 1 . In order to clearly show the medullary needle 300 inserted into the radius 500 in the wrist joint prosthesis of the present application, the radius 500 is hidden in FIG. 2 .

A wrist joint prosthesis includes a prosthesis body 100 , a medullary pin 300 and a biological fixing element 200 .

As shown in Figure 1, the prosthesis body 100 is fixed on the radius 500 near the metacarpal bone. The two ends of the prosthesis body 100 are respectively a first end 120 and a second end 130. The first end 120 is located at the end near the metacarpal bone, and the second end 130 is located at the end near the elbow joint. The end face of the second end 130 abuts against the end face of the resected part of the radius 500.

As shown in FIG. 2 , the medullary needle 300 is fixedly connected to the end surface of the second end 130, and the medullary needle 300 is used to be inserted into the medullary cavity of the radius 500, so that the prosthesis body 100 is fixed on the radius 500. Exemplarily, the outer diameter of the medullary needle 300 remains the same from the head end to the tail end; in another embodiment, the outer diameter of the medullary needle 300 gradually increases or decreases from the head end to the tail end. In another embodiment, the medullary needle 300 is arranged to extend along a straight line. In another embodiment, the medullary needle 300 is a rod structure with a certain curvature.

As shown in FIG. 1 and FIG. 3 , the biological fixing member 200 is fixedly mounted on the end surface of the first end portion 120 . Exemplarily, the biological fixing member 200 is fixedly mounted on the first end portion 120 by welding, bolt connection or clamping.

The biological fixation device 200 can provide different biological fixation interfaces. The biological fixation interface refers to the contact area between the artificial implant and the biological tissue. This area allows the biological tissue (such as bone tissue) to directly bind to the implant surface. In orthopedic implants, the design of the biological fixation interface is intended to promote the attachment, proliferation and differentiation of bone cells, thereby achieving a firm bond between the implant and the host bone. This bond is usually achieved through bone ingrowth or bone ongrowth, which helps to improve the stability and durability of the implant. Different biological fixation interfaces can provide different effects for the recovery of the patient's affected part. Different biological fixation interfaces are set according to the different situations faced by the patient. For example, when the wrist is dislocated, the biological fixation interface is configured as a porous block similar to the trabecular structure, which can promote wrist bone fusion and facilitate bone bridge formation; when the patient needs a better stabilization mechanism provided by the wrist prosthesis, the biological fixation device 200 is configured as a wrist joint surface, which can promote the recovery of the patient's wrist function.

In the wrist joint prosthesis provided in the embodiment of the present application, the medullary needle 300 fixes the prosthesis body 100 to the radius 500, and the prosthesis body 100 provides an installation basis for the biological fixation device 200 and the medullary needle 300. The biological fixation device 200 can provide different fixation interfaces according to the specific conditions of the patient, without the need to transplant bones elsewhere, thereby improving the adaptability of the wrist joint prosthesis and avoiding the disadvantages of dislocation, non-union, rejection or causing new trauma in the prior art.

In one embodiment, the biological fixing member 200 includes a first fixing block and a second fixing block which are separately arranged. The first fixing block has a first biological fixing interface, and the second fixing block has a second biological fixing interface. The first fixing block or the second fixing block is fixedly mounted on the first end 120 .

Initially, the first fixing block is installed on the first end 120. When the patient has different treatment needs, the first fixing block is removed from the first end 120 and the second fixing block is replaced on the first end 120, thereby providing the patient with different biological fixation interfaces and improving the adaptability of the wrist joint prosthesis.

In one embodiment, the first fixing block is a solid block made of polyethylene material. Exemplarily, a groove adapted to the wrist joint is configured on one end surface of the first fixing block close to the metacarpal bone, and the first biological fixing interface provided on the first fixing block is a smooth surface interface of the wrist joint.

The first fixing block is provided to reduce the compressive stress between the first biological fixing interface and the metacarpal bone, increase the contact area between the first fixing interface and the metacarpal bone, make the wrist joint prosthesis more compatible with the patient's original metacarpal bone, and provide the patient with a better wrist joint prosthesis locking mechanism, so that the patient can use the wrist joint prosthesis of this embodiment to bear weight, make the wrist joint prosthesis more consistent and reduce the stress on the biological fixing interface, thereby increasing the service life of the wrist joint prosthesis.

In one embodiment, the second fixing block is a block structure with a hollow porous structure, so that the second fixing block forms a porous block similar to a trabecular structure, which can promote wrist bone fusion.

As shown in FIG. 1 and FIG. 2 , in one embodiment, a fixing through hole 110 is provided on one end of the prosthesis body 100 near the first end 120. The fixing through hole 110 is provided so that the patient's ligament and joint capsule growth recovery requires a fixing foundation, and the fixing through hole 110 can provide a fixing foundation for the patient's ligament and joint capsule. During surgery, a bone screw can be fixed at the fixing through hole 110, and the ligament and joint capsule can be bound and sutured to the bone screw by sutures, thereby achieving fixation of the ligament and joint capsule. Of course, other methods can also be used to fix the ligament and joint capsule to the exposed part of the radius 500.

In one embodiment, more than one fixing through hole 110 is provided, and illustratively, one fixing through hole 110 is provided. As shown in FIG1 , in another embodiment, two fixing through holes 110 are provided, and the two fixing through holes 110 are distributed on the prosthesis body 100 around the axial direction of the radius 500. In another embodiment, four fixing through holes 110 are provided, and the four fixing through holes 110 are distributed on the prosthesis body 100 around the axial direction of the radius 500.

As shown in FIG1 , in one embodiment, the wrist joint prosthesis further includes a fixing plate 400, which is fixedly connected to the second end portion 130. The fixing plate 400 can provide a new fixing method for fixing the prosthesis body 100 on the radius 500. For example, screws can be set on the fixing plate 400 to fix the fixing plate 400 on the outer wall of the radius 500. Of course, the fixing plate 400 can also be tied to the outer wall of the radius 500 to fix the prosthesis body 100 on the radius 500, or the fixing plate 400 can be glued to the outer wall of the radius 500 to fix the prosthesis body 100 on the radius 500.

As shown in Figure 2, the fixing plate 400 and the medullary needle 300 are arranged parallel to each other (or at a certain angle) and there is a gap between them. After the medullary needle 300 is inserted into the radius 500, the outer wall of the radius 500 is located in the gap between the fixing plate 400 and the medullary needle 300. The outer wall of the radius 500 is clamped by the fixing plate 400 and the medullary needle 300, thereby limiting the displacement of the prosthesis body 100.

As shown in FIG. 1 , in one embodiment, the wrist joint prosthesis further includes a first fixing screw 410 , a first mounting hole is provided on the fixing plate 400 , and one end of the first fixing screw 410 is threadedly engaged with the first mounting hole; as shown in FIG. 2 , the other end of the first fixing screw 410 is fixedly mounted on the radius 500 , so that the fixing plate 400 is fixedly mounted on the radius 500 through the first fixing screw 410 .

A plurality of first fixing screws 410 are provided, and a plurality of first mounting holes are provided accordingly. By providing a plurality of first fixing screws 410 and corresponding first mounting holes, multi-point fixation of the fixing plate 400 on the radius 500 can be achieved. This multi-point fixation method can significantly improve the connection stability between the prosthesis body 100 and the radius 500, and prevent the prosthesis body 100 from loosening or shifting during use.

Among them, at least two first fixing screws 410 are used to limit the rotation and movement of the fixing plate 400, which can ensure that the fixing plate 400 maintains the correct position and posture after implantation, and avoid the position change of the prosthesis due to external force or patient activity, thereby ensuring the overall stability and functionality of the wrist joint prosthesis. And at least one of the first fixing screws 410 makes the fixing plate 400 closely contact with the radius 500, which helps to achieve a good fit between the wrist joint prosthesis and the radius 500, reduce postoperative pain and discomfort, and also help promote the fusion and healing between the bone and the wrist joint prosthesis.

1, the plurality of first mounting holes are arranged along a straight line, and accordingly, the first fixing screws 410 are arranged along a straight line. In another embodiment, the plurality of first mounting holes are arranged in two rows along two parallel straight lines, and accordingly, the first fixing screws 410 are arranged in two rows.

As shown in Figure 1, exemplarily, three first fixing screws 410 are provided, and three first mounting holes are correspondingly provided. Two first fixing screws 410 are used to limit the rotation and movement of the fixing plate 400, and one first fixing screw 410 makes the fixing plate 400 tightly abut against the radius 500. The pre-tightening force of the two first fixing screws 410 used to limit the fixing plate 400 is less than the pre-tightening force of the other first fixing screw 410 used to make the fixing plate 400 and the radius 500 tightly abut against each other.

Exemplarily, four first fixing screws 410 are provided, and four first mounting holes are correspondingly provided. Two first fixing screws 410 are used to limit the rotation and movement of the fixing plate 400, and the other two first fixing screws 410 are used to make the fixing plate 400 and the radius 500 tightly abut against each other.

As shown in FIG. 1 , in one embodiment, the wrist joint prosthesis further includes a second fixing screw, and a mounting slot 420 is provided on the fixing plate 400, and the mounting slot 420 is a key slot type through hole, and one end of the second fixing screw can be installed at different positions of the mounting slot 420, and the other end of the second fixing screw is fixedly installed on the radius 500. This design enables the surgeon to flexibly adjust the fixing position of the second fixing screw according to the specific conditions of the patient and the surgical requirements to adapt to the bone morphology and wrist joint structure of different patients, thereby improving the adaptability and personalization of the surgery. By adjusting the position of the second fixing screw, the contact surface between the wrist joint prosthesis and the radius 500 can be better matched and fixed, ensuring a close fit and stable connection between the wrist joint prosthesis and the radius 500. This helps to reduce the risk of loosening or displacement of the wrist joint prosthesis after surgery and improve the long-term effect of the surgery. Since the position of the second fixing screw is adjustable, the surgeon can select the optimal fixing position to disperse the stress concentration point of the wrist joint prosthesis when it is subjected to force. This helps to reduce the risk of damage to the wrist joint prosthesis or bone fatigue fracture caused by excessive local stress and protect the patient's wrist joint health.

As shown in FIG. 4 , in one embodiment, the wrist joint prosthesis further includes a connecting plate 750 , a fixing cable 700 , and a buckle.

The connecting plate 750 has two ends, which are respectively a first fixed end and a second fixed end. The first fixed end is located at one side of the prosthesis body 100 , and the second fixed end is located at one side of the radius 500 .

At least two fixing cables 700 are provided, at least one fixing cable 700 is used to bind the first fixing end and the prosthesis body 100, and at least one fixing cable 700 is used to bind and fix the second end 130 and the radius 500. At least two fixing cables 700 are provided to achieve multi-point fixation of the prosthesis body 100. The multi-point fixation method significantly enhances the connection stability between the wrist joint prosthesis and the bone, and reduces the risk of prosthesis loosening or displacement.

The buckle is used to fix the two ends of the position-limiting fixing cable 700 to prevent the fixing cable 700 from loosening. The buckle is used to fix the two ends of the fixing cable 700, which effectively prevents the fixing cable 700 from loosening due to uneven force or external force during use, ensures the durability and reliability of the fixation, and improves the safety and success rate of the operation.

4 , two fixing cables 700 are provided, one fixing cable 700 is used to bind the first fixing end and the prosthesis body 100, and the other fixing cable 700 is used to bind and fix the second end 130 and the radius 500. In another embodiment, four fixing cables 700 are provided, two fixing cables 700 are used to bind and fix the first fixing end and the prosthesis body 100, and the other two fixing cables 700 are used to bind and fix the second end 130 and the radius 500.

Exemplarily, the connecting plate 750 is made of human-friendly materials, such as human bones, titanium alloys, etc.

Exemplarily, the fixing cable 700 and the buckle are made of titanium alloy.

By providing the connecting plate 750, the fixing cable 700 and the buckle, the doctor can flexibly adjust according to the specific conditions of the patient and the surgical requirements. The surgeon can select the appropriate binding position and tightening strength according to factors such as the bone morphology, the degree of injury and the type of prosthesis to achieve the best fixation effect.

In all examples shown and described herein, any specific values should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims (10)

1. A wrist joint prosthesis, comprising: A prosthesis body (100), wherein the prosthesis body (100) is fixed to one end of the radius (500) close to the metacarpal bone, and the two ends of the prosthesis body (100) are respectively a first end (120) and a second end (130), wherein the first end (120) is located at the end close to the metacarpal bone, and the second end (130) is located at the end close to the elbow joint; a medullary needle (300), the medullary needle (300) being fixedly connected to the end surface of the second end portion (130), the medullary needle (300) being used to be inserted into the medullary cavity of the radius (500) so as to fix the prosthesis body (100) on the radius (500); A biological fixing member (200) is fixedly mounted on the end surface of the first end portion (120), and the biological fixing member (200) can provide different biological fixing interfaces. 2. The wrist joint prosthesis according to claim 1 is characterized in that the biological fixing component (200) includes a first fixing block and a second fixing block which are separately arranged, the first fixing block has a first biological fixing interface, the second fixing block has a second biological fixing interface, and the first fixing block or the second fixing block is fixedly installed on the first end (120). 3 . The wrist joint prosthesis according to claim 2 , wherein the first fixing block is a solid block made of polyethylene. 4 . The wrist joint prosthesis according to claim 2 , wherein the second fixing block is a block structure with a hollow porous structure. 5. The wrist joint prosthesis according to claim 1, characterized in that a fixing through hole (110) is provided on one end of the prosthesis body (100) close to the first end (120). 6. The wrist joint prosthesis according to claim 5, characterized in that there are more than one fixing through hole (110). 7. The wrist joint prosthesis according to claim 1, further comprising: A fixing plate (400), wherein the fixing plate (400) is fixedly connected to the second end portion (130), and the fixing plate (400) is arranged parallel to the medullary needle (300) with a gap therebetween. 8. The wrist joint prosthesis according to claim 7, further comprising: A first fixing screw (410), wherein a first mounting hole is provided on the fixing plate (400), one end of the first fixing screw (410) is threadedly engaged with the first mounting hole, and the other end of the first fixing screw (410) is fixedly mounted on the radius (500); A plurality of the first mounting holes are provided, and a plurality of the first fixing screws (410) are correspondingly provided, wherein at least two of the first fixing screws (410) are used to limit the rotation and movement of the fixing plate (400), and at least one of the first fixing screws (410) is used to make the fixing plate (400) tightly abut against the radius (500). 9. The wrist joint prosthesis according to claim 7, further comprising: A second fixing screw, wherein the fixing plate (400) is provided with a long mounting hole (420), wherein the long mounting hole (420) is a keyway-type through hole, and one end of the second fixing screw can be installed at different positions of the long mounting hole (420), and the other end of the second fixing screw is fixedly installed on the radius (500). 10. The wrist joint prosthesis according to claim 7, further comprising: A connecting plate (750), the connecting plate (750) having two ends, and the two ends are respectively a first fixed end and a second fixed end, the first fixed end is located on one side of the prosthesis body (100), and the second fixed end is located on one side of the radius (500); A fixing cable (700), wherein at least two fixing cables (700) are provided, at least one of the fixing cables (700) is used to bind the first fixing end and the prosthesis body (100), and at least one of the fixing cables (700) is used to bind and fix the second end (130) and the radius (500); A buckle is used to fix the two ends of the fixing cable (700) to prevent the fixing cable (700) from loosening.