wrist prosthesis

Abstract

The present invention provides a wrist joint prosthesis, comprising: a carpal prosthesis and a radial prosthesis; the carpal prosthesis having a first curved surface, the radial prosthesis having a second curved surface adapted to the shape of the first curved surface, the carpal prosthesis and the radial prosthesis being abutted against each other along a first direction via the first curved surface and the second curved surface; the carpal prosthesis being configured to be rotatable relative to the radial prosthesis about a second direction and a third direction perpendicular to the first direction, and one end of the carpal prosthesis for connection to the carpal bone being rotatable relative to one end of the radial prosthesis for connection to the radius about the first direction. With such a configuration, by configuring one end for connection to the carpal bone to be rotatable relative to one end of the radial prosthesis for connection to the radius about the first direction, the wrist joint prosthesis can realize the circumflex motion function of the radiocarpal joint, thereby improving the patient's wrist joint mobility and increasing patient satisfaction.

Description

Technical Field

[0001] The present invention relates to the technical field of orthopedic tools, and in particular to a wrist joint prosthesis. Background Art

[0002] The wrist joint is one of the most flexible and important joints in the human body. Previously, wrist fusion was the primary treatment for conditions such as traumatic and degenerative wrist arthritis, and severe rheumatoid wrist arthritis. However, with advances in medicine and technology, and patients' urgent desire to resolve pain while preserving wrist function, total wrist replacement is increasingly being used in wrist treatment. Currently, wrist prostheses have evolved into non-restrictive total wrist prostheses, capable of achieving palmar flexion, dorsiflexion, ulnar deviation, and radial deviation. However, current wrist prostheses are unable to achieve circumflexion of the radiocarpal joint. Summary of the Invention

[0003] The object of the present invention is to provide a wrist joint prosthesis to solve the problem that existing wrist joint prostheses cannot achieve the circumflex motion function of the radiocarpal joint.

[0004] In order to solve the above technical problems, the present invention provides a wrist joint prosthesis, which includes: a carpal prosthesis and a radial prosthesis; the carpal prosthesis has a first curved surface, the radial prosthesis has a second curved surface adapted to the shape of the first curved surface, and the carpal prosthesis and the radial prosthesis are abutted and connected along a first direction through the first curved surface and the second curved surface; the carpal prosthesis is configured to be rotatable relative to the radial prosthesis around a second direction and a third direction perpendicular to the first direction, respectively, and one end of the carpal prosthesis for connecting to the carpal bone is rotatable around the first direction relative to the one end of the radial prosthesis for connecting to the radius.

[0005] Optionally, the carpal prosthesis includes a connected carpal support and a carpal connector, the carpal support is used to connect to the carpal bone, the first curved surface is located on the side of the carpal connector away from the carpal support, one of the carpal support and the carpal connector has a first convex portion, and the other has a first concave portion adapted to the first convex portion; the first convex portion is used to engage with the first concave portion, and the first convex portion is rotatable around the first direction relative to the first concave portion.

[0006] Optionally, one of the carpal support and the carpal connector has a second protrusion, and the other has a second recess; the second protrusion is configured to abut against and be restricted by the second recess when the rotation angle of the carpal support around the first direction relative to the carpal connector reaches a preset travel range, thereby limiting the rotation angle of the carpal support around the first direction relative to the carpal connector to not exceed the preset travel range.

[0007] Optionally, the first protrusion and the first recess are both cylindrical, one of the first protrusion and the first recess has a limiting ring arranged around its circumference, and the other has a limiting groove adapted to the limiting ring, and the limiting ring is used to engage with the limiting groove to limit the relative displacement of the first protrusion and the first recess along the axial direction.

[0008] Optionally, both the first convex portion and the first concave portion include a spherical area, and the spherical area of ​​the first convex portion is adapted to the diameter of the spherical area of ​​the first concave portion, wherein the opening diameter of the spherical area of ​​the first concave portion is smaller than the diameter of the spherical area of ​​the first convex portion, and the spherical area of ​​the first convex portion is used to be engaged with the spherical area of ​​the first concave portion, and then restricted from displacement along the opening direction by the spherical area of ​​the first concave portion.

[0009] Optionally, the carpal prosthesis includes a connected carpal support and a carpal connector, the first curved surface is located on the side of the carpal connector away from the carpal support, the first curved surface and the second curved surface are both spherical, and the carpal connector can rotate relative to the radial prosthesis around the first direction, the second direction and the third direction respectively through the abutment between the first curved surface and the second curved surface.

[0010] Optionally, the wrist support includes a wrist support platform and two first side wings extending along the second direction, the two first side wings are respectively arranged on both sides of the wrist support platform along the second direction, and extend in a direction away from the wrist connector, and each first side wing forms an angle of no more than 60° with the wrist support platform.

[0011] Optionally, the carpal bone connector includes two second side wings extending along the second direction, and the second side wings are used to be in abutment connection with the first side wings.

[0012] Optionally, the wrist bone support and the wrist bone connector are integrally formed.

[0013] Optionally, one of the carpal support and the carpal connector has a tapered protrusion, and the other has a tapered hole adapted to the tapered protrusion, and the carpal support and the carpal connector are detachably connected to the tapered hole via the tapered protrusion.

[0014] Optionally, the wrist bone support has a cancellous nail hole for passing a cancellous bone screw; wherein the diameter of the cancellous nail hole is larger than the diameter of the cancellous bone screw.

[0015] Optionally, the radial prosthesis includes a connected radial connector and a radial stem, the radial stem is used to connect to the radius, the second curved surface is located on the side of the radial connector away from the radial stem, one of the radial connector and the radial stem has a third convex portion, and the other has a third concave portion adapted to the third convex portion; the third convex portion is used to engage with the third concave portion, and the third convex portion is rotatable relative to the third concave portion around the first direction.

[0016] Optionally, the carpal prosthesis includes a connected carpal support and a carpal connector, the carpal support is used to connect to the carpal bone, the first curved surface is located on the side of the carpal connector away from the carpal support, one of the carpal support and the carpal connector has a limiting boss, and the other has a limiting recessed area adapted to the limiting boss, the limiting boss is used to engage with the limiting recessed area to limit the rotation and radial movement of the carpal support relative to the carpal connector.

[0017] Optionally, one of the radial connector and the radial stem has a fourth protrusion, and the other has a fourth recess; the fourth protrusion is configured to abut against and be restricted by the fourth recess when the rotation angle of the radial connector relative to the radial stem around the first direction reaches a preset travel range, thereby limiting the rotation angle of the radial connector relative to the radial stem around the first direction to not exceed the preset travel range.

[0018] Optionally, the first curved surface and the second curved surface are both ellipsoidal surfaces, and the carpal prosthesis is rotatable relative to the radial prosthesis around the second direction and the third direction respectively due to the abutment between the first curved surface and the second curved surface.

[0019] Optionally, one of the first curved surface and the second curved surface is a concave surface, and the other is a convex surface.

[0020] In summary, the wrist joint prosthesis provided by the present invention includes: a carpal prosthesis and a radial prosthesis; the carpal prosthesis has a first curved surface, the radial prosthesis has a second curved surface adapted to the shape of the first curved surface, and the carpal prosthesis and the radial prosthesis are abutted and connected along a first direction through the first curved surface and the second curved surface; the carpal prosthesis is configured to be rotatable relative to the radial prosthesis around a second direction and a third direction perpendicular to the first direction, respectively, and one end of the carpal prosthesis for connecting to the carpal bone is rotatable around the first direction relative to the one end of the radial prosthesis for connecting to the radius.

[0021] In this configuration, by configuring the end for connecting to the wrist bone to be rotatable around a first direction relative to the end of the radial prosthesis for connecting to the radius, the wrist joint prosthesis can realize the circumferential movement function of the radiocarpal joint, improve the patient's wrist joint mobility, and increase patient satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0023] Figure 1 is an exploded schematic diagram of a wrist joint prosthesis according to a first embodiment of the present invention;

[0024] Figure 2 1 is a schematic diagram of the assembly of the wrist joint prosthesis according to the first embodiment of the present invention;

[0025] Figure 3 yes Figure 2 The schematic cross-sectional view of the wrist joint prosthesis shown is along the line AA;

[0026] Figure 4 yes Figure 3 Enlarged view of the middle G section;

[0027] Figure 5 is a schematic diagram of a wrist support according to a first embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of a wrist bone connector according to a first embodiment of the present invention;

[0029] Figure 7 is a schematic diagram of a radial prosthesis according to a first embodiment of the present invention;

[0030] Figure 8 is an exploded schematic diagram of a wrist joint prosthesis according to a second embodiment of the present invention;

[0031] Figure 9 is a schematic diagram of the assembly of a wrist joint prosthesis according to the second embodiment of the present invention;

[0032] Figure 10 yes Figure 9 The schematic cross-sectional view of the wrist joint prosthesis shown is along the line BB;

[0033] Figure 11 is a schematic diagram of a wrist support according to a second embodiment of the present invention;

[0034] Figure 12 is a schematic diagram of a wrist bone connector according to a second embodiment of the present invention;

[0035] Figure 13 is a schematic diagram of a radial prosthesis according to a second embodiment of the present invention;

[0036] Figure 14 is a schematic diagram of the assembly of a wrist joint prosthesis according to a third embodiment of the present invention;

[0037] Figure 15 yes Figure 14 The schematic cross-sectional view of the wrist prosthesis shown is along the CC line;

[0038] Figure 16 is a schematic diagram of a wrist support according to a third embodiment of the present invention;

[0039] Figure 17 is a schematic diagram of a wrist bone connector according to a third embodiment of the present invention;

[0040] Figure 18 is a schematic diagram of a radial prosthesis according to a third embodiment of the present invention;

[0041] Figure 19 is a schematic diagram of another preferred example of a carpal prosthesis according to the third embodiment of the present invention;

[0042] Figure 20 is a schematic diagram of the assembly of a wrist joint prosthesis according to a fourth embodiment of the present invention;

[0043] Figure 21 yes Figure 20 The schematic cross-sectional view of the wrist prosthesis shown is along the line DD;

[0044] Figure 22 is a schematic diagram of a wrist support according to a fourth embodiment of the present invention;

[0045] Figure 23 is a schematic diagram of a wrist bone connector according to a fourth embodiment of the present invention;

[0046] Figure 24 is a schematic diagram of a radial connector according to a fourth embodiment of the present invention;

[0047] Figure 25 is a schematic diagram of a radial handle according to a fourth embodiment of the present invention;

[0048] Figure 26 is a schematic diagram of the assembly of a wrist joint prosthesis according to a fifth embodiment of the present invention;

[0049] Figure 27 yes Figure 26 The schematic cross-sectional view of the wrist prosthesis shown is along line EE;

[0050] Figure 28 is a schematic diagram of a wrist support according to a fifth embodiment of the present invention;

[0051] Figure 29 is a schematic diagram of a wrist bone connector according to a fifth embodiment of the present invention;

[0052] Figure 30 yes Figure 29The schematic cross-sectional view of the radial connector along line FF is shown;

[0053] Figure 31 is a schematic diagram of a radial connector according to a fifth embodiment of the present invention;

[0054] Figure 32 Schematic diagram of the radial handle according to the fifth embodiment of the present invention.

[0055] In the attached figure:

[0056] 10-carpal prosthesis; 11-carpal support; 12-carpal connector; 20-radial prosthesis; 21-radial handle; 22-radial connector; 30-cancellous bone screw;

[0057] 110 - carpal support platform; 111 - first convex portion; 112 - second convex portion; 113 - limiting ring; 114 - column; 115 - cancellous nail hole; 116 - tapered protrusion; 117 - first wing; 118 - limiting recessed area; 120 - first curved surface; 121 - first concave portion; 122 - second concave portion; 123 - limiting groove; 126 - tapered hole; 127 - second wing; 128 - limiting boss;

[0058] 211 - third concave portion; 212 - fourth convex portion; 213 - limiting groove; 220 - second curved surface; 221 - third convex portion; 222 - fourth concave portion; 223 - limiting ring. DETAILED DESCRIPTION

[0059] To make the objects, advantages, and features of the present invention more clearly apparent, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale. They are only used to conveniently and clearly assist in illustrating the purposes of the embodiments of the present invention. In addition, the structures shown in the drawings are often part of the actual structure. In particular, different drawings may need to illustrate different focuses and sometimes use different scales.

[0060] As used in the present invention, the singular forms "a", "an" and "the" include plural objects, the term "or" is generally used to include the meaning of "and / or", the term "several" is generally used to include the meaning of "at least one", and the term "at least two" is generally used to include the meaning of "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, and "one end" and "the other end" generally refer to two corresponding parts, which include not only endpoints, unless the content clearly indicates otherwise.

[0061] The core idea of ​​the present invention is to provide a wrist joint prosthesis to solve the problem that existing wrist joint prostheses cannot achieve the rotation function of the radiocarpal joint.

[0062] The following describes several embodiments with reference to the accompanying drawings.

[0063] [Example 1]

[0064] Please refer to Figures 1 to 7 ,in, Figure 1 is an exploded schematic diagram of a wrist joint prosthesis according to a first embodiment of the present invention; Figure 2 1 is a schematic diagram of the assembly of the wrist joint prosthesis according to the first embodiment of the present invention; Figure 3 yes Figure 2 The schematic cross-sectional view of the wrist joint prosthesis shown is along the line AA; Figure 4 yes Figure 3 Enlarged view of the middle G section; Figure 5 is a schematic diagram of a wrist support according to a first embodiment of the present invention; Figure 6 is a schematic diagram of a wrist bone connector according to a first embodiment of the present invention; Figure 7 Schematic diagram of a radial prosthesis according to a first embodiment of the present invention.

[0065] like Figure 1 As shown, a first embodiment of the present invention provides a wrist joint prosthesis, which includes: a carpal prosthesis 10 and a radial prosthesis 20; the carpal prosthesis 10 has a first curved surface 120, and the radial prosthesis 20 has a second curved surface 220 adapted to the shape of the first curved surface 120, and the carpal prosthesis 10 and the radial prosthesis 20 are abutted and connected along a first direction through the first curved surface 120 and the second curved surface 220; the carpal prosthesis 10 is configured to be rotatable relative to the radial prosthesis 20 around a second direction and a third direction perpendicular to the first direction, respectively, and the end of the carpal prosthesis 10 for connecting to the carpal bone is rotatable around the first direction relative to the end of the radial prosthesis 20 for connecting to the radius.

[0066] The inventors discovered that the movement direction of the wrist joint is composed of anatomical basis, mainly including: palmar flexion, dorsiflexion, ulnar deviation, radial deviation and circumduction. Figure 1For the wrist joint prosthesis provided in this embodiment, palmar flexion and dorsiflexion refer to rotation around the Y axis; radial deviation and ulnar deviation refer to rotation around the X axis; and circumflexion of the radiocarpal joint refers to rotation around the Z axis. Generally, in order to restore the natural movement of the wrist joint, under ideal conditions, the range of motion that the wrist joint prosthesis needs to meet is: palmar flexion 5°, dorsiflexion 6°, radial deviation 7°, ulnar deviation 6°, and radiocarpal rotation ±7°. However, most of the carpal joint pseudoarticular surfaces currently on the market are ellipsoidal structures, so they can only achieve palmar flexion, dorsiflexion, radial deviation and ulnar deviation (i.e., rotation around the X and Y axes), and cannot achieve the circumflexion function of the radiocarpal joint (i.e., rotation around the Z axis). Based on the above research, in the wrist joint prosthesis provided in this embodiment, the carpal prosthesis 10 is configured to be rotatable relative to the radial prosthesis 20 around a first direction, thereby enabling the wrist joint prosthesis to achieve the circumflexion function of the radiocarpal joint, improve the patient's wrist joint range of motion, and increase patient satisfaction. It can be understood that the above-mentioned first direction corresponds to the Z axis, the second direction corresponds to the Y axis, and the third direction corresponds to the X axis.

[0067] Please refer to Figures 1 to 6 Preferably, the carpal prosthesis 10 includes a connected carpal support 11 and a carpal connector 12. The carpal support 11 is used to connect to the carpal bone. The first curved surface 120 is located on the side of the carpal connector 12 away from the carpal support 11. One of the carpal support 11 and the carpal connector 12 has a first protrusion 111, and the other has a first recess 121 that matches the first protrusion 111. The first protrusion 111 is used to snap into the first recess 121, and the first protrusion 111 is rotatable relative to the first recess 121 about the first direction. In an exemplary embodiment, the carpal support 11 has the first protrusion 111, and the carpal connector 12 has the first recess 121. The first protrusion 111 is detachably inserted into the first recess 121, thereby achieving rotatable assembly of the carpal support 11 and the carpal connector 12. More specifically, the surfaces of the carpal support 11 and the carpal connector 12 that are opposite to each other are planes parallel to the X-axis and the Y-axis, and the first protrusion 111 extends and protrudes toward the carpal connector 12 along the Z-axis, and the first recess 121 is recessed along the Z-axis. After the first protrusion 111 is snap-fitted into the first recess 121, the carpal support 11 and the carpal connector 12 are rotatably against each other around the Z-axis. It will be understood by those skilled in the art that in other embodiments, the carpal support 11 may have the first recess 121 and the carpal connector 12 may have the first protrusion 111, and the effects achieved are similar. With this configuration, the carpal prosthesis 10 itself has the freedom to rotate around the Z-axis, so the carpal prosthesis 10 can achieve the circumferential movement function of the radiocarpal joint by rotating the carpal support 11 relative to the carpal connector 12.

[0068] Optionally, the first convex portion 111 and the first concave portion 121 are both cylindrical, one of the first convex portion 111 and the first concave portion 121 has a limiting ring 113 arranged around its circumference, and the other has a limiting groove 123 adapted to the limiting ring 113, and the limiting ring 113 is used to engage with the limiting groove 123 to limit the relative displacement of the first convex portion 111 and the first concave portion 121 along the axial direction. Figure 5 and Figure 6 As shown, in one exemplary embodiment, the first protrusion 111 includes a retaining ring 113, which protrudes annularly from the cylindrical outer surface of the first protrusion 111. The first recess 121 includes a retaining groove 123, which is annularly recessed into the cylindrical inner surface of the first recess 121. After the first protrusion 111 is inserted into the first recess 121, the retaining ring 113 can be engaged with the retaining groove 123, thereby restricting the axial displacement of the first protrusion 111 relative to the first recess 121. This allows the carpal support 11 and the carpal connector 12 to have relative circumferential rotational freedom after the first protrusion 111 and the first recess 121 are assembled and connected. Preferably, the retaining ring 113 and the first recess 121 have an interference fit, and the retaining ring 113 is assembled into the first recess 121 in an interference fit manner until it engages with the retaining groove 123. Of course, in some other embodiments, the limiting ring 113 may be provided on the first concave portion 121 , and the limiting groove 123 may be provided on the first convex portion 111 .

[0069] For further information, please refer to Figure 1 、 Figure 2 、 Figure 5 and Figure 6 One of the wrist support 11 and the wrist connector 12 has a second convex portion 112, and the other has a second concave portion 122; the second convex portion 112 is configured to abut against the second concave portion 122 and be restricted by the second concave portion 122 when the rotation angle of the wrist support 11 relative to the wrist connector 12 around the first direction reaches a preset range of travel, thereby restricting the rotation angle of the wrist support 11 relative to the wrist connector 12 around the first direction from exceeding the preset range of travel. Figure 5 and Figure 6 As shown, in an exemplary embodiment, the carpal support 11 has a second protrusion 112, which extends and protrudes toward the carpal connector 12, and a second recess 122 is formed on the side of the carpal connector 12 facing the carpal support 11. The circumferential length of the second recess 122 around the Z axis is greater than the circumferential length of the second protrusion 112 around the Z axis, so that the second protrusion 112 can move in the second recess 122. Preferably, as Figure 2As shown, when the wrist support 11 and the carpal connector 12 are assembled and in the initial state, the wrist support 11 and the carpal connector 12 do not rotate relative to each other around the Z axis. At this time, the second protrusion 112 is preferably located in the middle of the second recess 122. When the wrist support 11 and the carpal connector 12 rotate relative to each other around the Z axis to a certain angle (clockwise or counterclockwise), the second protrusion 112 will come into contact with one side of the second recess 122, thereby being restricted from further rotation by the second recess 122. This defines a preset range of travel for the rotation angle between the wrist support 11 and the carpal connector 12. In one embodiment, the preset range of travel is -20° to +20°. In another embodiment, the preset range of travel is -10° to +10°. The former has a larger range of motion, while the latter is closer to the natural range of motion of the wrist joint.

[0070] Optionally, the first curved surface 120 and the second curved surface 220 are both ellipsoidal surfaces, the first curved surface 120 is convex, and the second curved surface 220 is concave. The carpal prosthesis 10 is rotatable relative to the radial prosthesis 20 around the second direction (Y-axis) and the third direction (X-axis) respectively through the abutment between the first curved surface 120 and the second curved surface 220. Preferably, the short axis of the ellipsoidal surface is arranged along the X-axis direction, and the long axis is arranged along the Y-axis direction. Preferably, the roughness Ra of the first curved surface 120 is ≤2μm, and the roughness Ra of the second curved surface 220 is ≤0.1μm. The first curved surface 120 and the second curved surface 220 are both polished so that the carpal prosthesis 10 and the radial prosthesis 20 can rotate smoothly relative to each other to reduce wear.

[0071] Please refer to Figure 7 In an alternative embodiment, the radial prosthesis 20 includes a radial connector 22 and a radial stem 21 connected to each other, and the second curved surface 220 is located on the side of the radial connector 22 away from the radial stem 21, and the radial stem 21 is used to connect to the radius, such as being insertable into the radial medullary cavity. In contrast, the wrist support 11 includes a wrist support platform 110 and a column 114 extending in the direction away from the radial prosthesis 20 along the Z axis. The wrist support platform 110 is roughly in the shape of an elliptical plate, with its long axis extending in a direction parallel to the Y axis and its short axis extending in a direction parallel to the X axis. The column 114 is arranged on the side of the wrist support platform 110 away from the radial prosthesis 20. In use, the wrist support platform 110 is used to contact the carpal bone, and the column 114 is used to connect to the carpal bone, such as being insertable into the capitate bone. Preferably, the wrist support 11 and the radial prosthesis 20 are connected to the carpal bone and the radius respectively by biological fixation or bone cement fixation. If biological fixation is used, the surface of the carpal support platform 110, the surface in contact with the carpal bone, the column 114, and the surface of the radial stem 21 are preferably coated or porous to facilitate bone ingrowth and achieve a long-term stable connection. Preferably, the radial connector 22 is fixedly connected to the radial stem 21.

[0072] The ellipsoidal first and second curved surfaces 120, 220 allow the carpal prosthesis 10 and radial prosthesis 20 to rotate relative to each other along the X and Y axes, but not about the Z axis. However, the ellipsoidal first and second curved surfaces 120, 220, better conform to human anatomy than a spherical shape, improving the reliability of palmar flexion, dorsiflexion, ulnar deviation, and radial deviation. Furthermore, the rotational connection between the first convex portion 111 and the first concave portion 121 enables circumferential rotation of the radiocarpal joint without compromising the reliability of palmar flexion, dorsiflexion, ulnar deviation, and radial deviation.

[0073] Preferably, the wrist bone support 11 has a cancellous nail hole 115 for passing the cancellous bone screw 30; wherein, the diameter of the cancellous nail hole 115 is larger than the diameter of the cancellous bone screw 30. With such a configuration, the assembly between the wrist bone support 11 and the cancellous bone screw 30 can achieve a certain deflection angle, and can provide more direction options for driving the cancellous bone screw 30 into the wrist bone. Specifically, when the diameter of the cancellous nail hole 115 is larger than the diameter of the cancellous bone screw 30, the cancellous bone screw 30 can be nailed into the wrist bone at a certain angle to the axial direction of the cancellous nail hole 115, so as to facilitate the operator's operation during surgery. Furthermore, the wrist bone support 11 has two cancellous nail holes 115, and the two cancellous nail holes 115 are located on the long axis of the wrist bone support platform 110 and are symmetrically distributed about the column 114.

[0074] The following is an example to illustrate the steps of using the wrist joint prosthesis provided by this embodiment:

[0075] During the operation, osteotomy is first performed on the carpal side. After the osteotomy is completed, the carpal support 11 is installed on the carpal bone where the osteotomy has been completed. The upper column 114 of the carpal support 11 is inserted into the capitate bone, and the carpal support platform 110 contacts the carpal bone. Then, the cancellous bone screw 30 is driven into the carpal bone through the cancellous nail hole 115 on the carpal support 11 to fix the carpal support and the carpal bone.

[0076] After the wrist support 11 is installed, assemble the wrist support 11 with the wrist connector 12, insert the first protrusion 111 into the first recess 121, engage the limiting ring 113 into the limiting groove 123, and ensure that the second protrusion 112 is located in the second recess 122.

[0077] After the carpal connector 12 is installed, the radial stem 21 is inserted into the radial medullary cavity so that the second curved surface 220 on the radial prosthesis 20 contacts the first curved surface 120 on the carpal prosthesis 10. Finally, the wrist joint is assembled and reset to complete the implantation of the wrist joint prosthesis.

[0078] [Example 2]

[0079] Please refer to Figures 8 to 13 ,in, Figure 8is an exploded schematic diagram of a wrist joint prosthesis according to a second embodiment of the present invention; Figure 9 is a schematic diagram of the assembly of a wrist joint prosthesis according to the second embodiment of the present invention; Figure 10 yes Figure 9 The schematic cross-sectional view of the wrist joint prosthesis shown is along the line BB; Figure 11 is a schematic diagram of a wrist support according to a second embodiment of the present invention; Figure 12 is a schematic diagram of a wrist bone connector according to a second embodiment of the present invention; Figure 13 Schematic diagram of a radial prosthesis according to a second embodiment of the present invention.

[0080] The wrist joint prosthesis provided in the second embodiment of the present invention is substantially the same as the wrist joint prosthesis provided in the first embodiment, and the same parts will not be described again. Only the differences will be described below.

[0081] In the second embodiment, the arrangement of the first convex portion 111, the second convex portion 112, the first concave portion 121, and the second concave portion 122 differs from that in the first embodiment. In the second embodiment, the first convex portion 111 and the first concave portion 121 both include spherical regions, and the diameter of the spherical region of the first convex portion 111 matches the diameter of the spherical region of the first concave portion 121. The opening diameter of the spherical region of the first concave portion 121 is smaller than the diameter of the spherical region of the first convex portion 111. After the spherical region of the first convex portion 111 is engaged with the spherical region of the first concave portion 121, the spherical region of the first concave portion 121 restricts displacement along the opening direction.

[0082] Specifically, the spherical area of ​​the first protrusion 111 is larger than a hemisphere and protrudes in the direction of the radial prosthesis 20. The spherical area of ​​the first recess 121 is a recessed area larger than a hemisphere, and its opening is oriented toward the carpal support 11. Because the spherical area of ​​the first recess 121 is larger than a hemisphere, its opening diameter is smaller than its maximum inner diameter. When the first protrusion 111 is inserted into the first recess 121 in an interference fit, it is restricted by the opening of the first recess 121 and will not fall out. In addition, because both the first protrusion 111 and the first recess 121 are spherical, circumferential relative rotation is not restricted. As a result, after the carpal support 11 and the carpal connector 12 are assembled and connected through the first protrusion 111 and the first recess 121, they have relative circumferential rotational freedom while being restricted in axial relative movement. The spherical first convex portion 111 and the first concave portion 121 can omit the limiting ring 113 and the limiting groove 123, thereby simplifying the structure and reducing the difficulty of assembly.

[0083] Furthermore, in the second embodiment, the carpal support 11 has two second protrusions 112, and correspondingly, the carpal connector 12 has two second recesses 122. The two second protrusions 112 are spaced apart circumferentially along the carpal support platform 110. This configuration improves the limiting reliability of the circumferential movement of the radiocarpal joint.

[0084] [Example 3]

[0085] Please refer to Figures 14 to 19 ,in, Figure 14 is a schematic diagram of the assembly of a wrist joint prosthesis according to a third embodiment of the present invention; Figure 15 yes Figure 14 The schematic cross-sectional view of the wrist prosthesis shown is along the CC line; Figure 16 is a schematic diagram of a wrist support according to a third embodiment of the present invention; Figure 17 is a schematic diagram of a wrist bone connector according to a third embodiment of the present invention; Figure 18 is a schematic diagram of a radial prosthesis according to a third embodiment of the present invention; Figure 19 It is a schematic diagram of a carpal prosthesis according to another preferred example of the third embodiment of the present invention.

[0086] The wrist joint prosthesis provided in the third embodiment of the present invention is substantially the same as the wrist joint prosthesis provided in the first embodiment, and the same parts will not be described again. Only the differences will be described below.

[0087] In this third embodiment, the configuration of the first curved surface 120, the second curved surface 220, the carpal support 11, and the carpal connector 12 differs from that of the first embodiment. In the third embodiment, the first curved surface 120 and the second curved surface 220 are both spherical surfaces, with the first curved surface 120 being convex and the second curved surface 220 being concave. The carpal connector 12 is rotatable relative to the radial prosthesis 20 about the first, second, and third directions, respectively, due to the abutment between the first curved surface 120 and the second curved surface 220.

[0088] In the third embodiment, the wrist support 11 and the wrist connector 12 may not have the freedom to rotate around the Z axis. In some embodiments, the wrist support 11 and the wrist connector 12 may be in a fixed connection relationship after assembly connection, such as Figure 16 and Figure 17 In some other embodiments, the carpal support 11 and the carpal connector 12 can also be integrally formed, such as Figure 19 As shown, the first curved surface 120 and the second curved surface 220 are both spherical, so they can rotate relative to each other on the X-axis and the Y-axis, and can also rotate around the Z-axis, thereby simultaneously achieving palmar flexion, dorsiflexion, ulnar deviation, radial deviation and circumferential rotation of the radiocarpal joint.

[0089] For further information, please refer to Figure 16 The wrist support 11 includes a wrist support platform 110 and two first side wings 117 extending along the second direction. The two first side wings 117 are respectively arranged on both sides of the wrist support platform 110 along the second direction and extend in a direction away from the wrist connector 12. Each of the first side wings 117 forms an angle of no more than 60° with the wrist support platform 110 (i.e., Figure 16 The angle α in the figure is ≤60°. During use, the carpal support platform 110 and the first side wings 117 on both sides of the carpal support 11 are used to contact the carpal osteotomy surface. On the one hand, this increases the contact area with the carpal osteotomy surface. On the other hand, the first side wings 117 on both sides of the carpal support 11 form a tilted shape, which increases the range of motion of the wrist joint prosthesis in radial deviation and ulnar deviation (i.e., rotation about the X-axis). On the other hand, the entire carpal support 11 is formed into a shape with a Y-axis length greater than the X-axis length, which is more in line with the anatomical characteristics of the human body. On the premise of satisfying the circumferential movement of the radiocarpal joint, the reliability of palmar flexion, dorsiflexion, ulnar deviation, and radial deviation is improved.

[0090] For further information, please refer to Figure 17 The carpal connector 12 includes two second side wings 127 extending along the second direction, and the second side wings 127 are used to be closely connected with the first side wings 117 to make the assembly connection between the carpal connector 12 and the carpal support 11 more reliable, so that the carpal connector 12 and the carpal support 11 will not produce relative rotation around the X-axis.

[0091] Optional, such as Figure 16 and Figure 17 As shown, one of the carpal support 11 and the carpal connector 12 has a tapered protrusion 116, and the other has a tapered hole 126 that matches the tapered protrusion 116. The carpal support 11 and the carpal connector 12 are detachably connected via the tapered protrusion 116 and the tapered hole 126. In an exemplary embodiment, the carpal support 11 has the tapered protrusion 116, which is protruding from the carpal support platform 110 toward the carpal connector 12 and gradually shrinks away from the carpal support platform 110. Correspondingly, a conical hole 126 is recessed and formed on the side of the carpal connector 12 facing the carpal support 11. The shape of the conical hole 126 is adapted to the shape of the conical protrusion 116. When the carpal support 11 and the carpal connector 12 are assembled and connected, the conical protrusion 116 is inserted into the conical hole 126 to form a conical fit, thereby realizing the function of locking the carpal support 11 and the carpal connector 12.

[0092] Optionally, the wrist support 11 has two cancellous nail holes 115, which are located on the first side wing 117 and symmetrically distributed about the column 114. Figure 14 and Figure 15 As shown, the axes of the two cancellous nail holes 115 are preferably perpendicular to the extension direction of the first wing 117, so that the cancellous bone screws 30 can be nailed into the carpal bone at an angle to improve the connection strength.

[0093] [Example 4]

[0094] Please refer to Figures 20 to 25 ,in, Figure 20is a schematic diagram of the assembly of a wrist joint prosthesis according to a fourth embodiment of the present invention; Figure 21 yes Figure 20 The schematic cross-sectional view of the wrist prosthesis shown is along the line DD; Figure 22 is a schematic diagram of a wrist support according to a fourth embodiment of the present invention; Figure 23 is a schematic diagram of a wrist bone connector according to a fourth embodiment of the present invention; Figure 24 is a schematic diagram of a radial connector according to a fourth embodiment of the present invention; Figure 25 Schematic diagram of the radial handle according to the fourth embodiment of the present invention.

[0095] The wrist joint prosthesis provided in the fourth embodiment of the present invention is substantially the same as the wrist joint prosthesis provided in the first embodiment, and the same parts will not be described again. Only the differences will be described below.

[0096] In this fourth embodiment, the method for achieving the circumferential motion function of the radiocarpal joint is different from that in the first embodiment. In the fourth embodiment, the radial prosthesis 20 itself has the degree of freedom to rotate about the Z axis. Therefore, the radial prosthesis 20 can achieve the circumferential motion function of the radiocarpal joint by rotating the radial stem 21 relative to the radial connector 22.

[0097] For details, please refer to Figure 24 and Figure 25 One of the radial connector 22 and the radial handle 21 has a third protrusion 221, and the other has a third recess 211 adapted to the third protrusion 221; the third protrusion 221 is used to engage with the third recess 211, and the third protrusion 221 is rotatable relative to the third recess 211 around the first direction. In one exemplary embodiment, the opposing surfaces of the radial stem 21 and the radial connector 22 are both planes parallel to the X-axis and the Y-axis. The radial connector 22 has a third protrusion 221 that extends and projects toward the radial stem 21 along the Z-axis. The third protrusion 221 is recessed along the Z-axis on the side of the radial stem 21 facing the radial connector 22. When the third protrusion 221 is engaged with the third recess 211, the radial stem 21 and the radial connector 22 are rotatably abutted about the Z-axis. As will be appreciated by those skilled in the art, in other embodiments, the radial connector 22 may have the third recess 211 while the radial stem 21 may have the third protrusion 221, achieving similar effects. With this configuration, the carpal prosthesis 10 itself has the freedom to rotate about the Z-axis. Therefore, the radial prosthesis 20 can achieve circumferential rotation of the radiocarpal joint by rotating the radial stem 21 relative to the radial connector 22.

[0098] Optionally, the third protrusion 221 and the third recess 211 are both cylindrical, with one of the third protrusion 221 and the third recess 211 having a limiting ring 223 disposed circumferentially around the cylinder, and the other having a limiting groove 213 adapted to the limiting ring 223. The limiting ring 223 is configured to engage with the limiting groove 213 to limit axial displacement of the third protrusion 221 and the third recess 211 along the cylinder. After the third protrusion 221 is inserted into the third recess 211, the limiting ring 223 can engage with the limiting groove 213, thereby limiting axial displacement of the third protrusion 221 relative to the third recess 211. This allows the radial stem 21 and the radial connector 22 to have relative circumferential rotational freedom after being assembled and connected by the third protrusion 221 and the third recess 211. Preferably, the limiting ring 223 and the third recess 211 have an interference fit, and the limiting ring 223 is assembled into the third recess 211 by interference fit until it engages with the limiting groove 213. In some embodiments, the limiting ring 223 is provided on the third protrusion 221, and the limiting groove 213 is provided on the third recess 211; of course, in other embodiments, the limiting ring 223 may also be provided on the third recess 211, while the limiting groove 213 may be provided on the third protrusion 221.

[0099] Furthermore, one of the radial connector 22 and the radial stem 21 has a fourth protrusion 212, and the other has a fourth recess 222. The fourth protrusion 212 is configured to abut against and be restrained by the fourth recess 222 when the radial connector 22 reaches a predetermined range of rotation relative to the radial stem 21 about the first direction, thereby limiting the rotation of the radial connector 22 about the first direction relative to the radial stem 21 to within the predetermined range. In some embodiments, the fourth protrusion 212 is provided on the radial stem 21, and the fourth recess 222 is provided on the radial connector 22. In other embodiments, the fourth protrusion 212 may be provided on the radial connector 22, while the fourth recess 222 may be provided on the radial stem 21. The structure and design principles of the fourth protrusion 212 and the fourth recess 222 are similar to those of the second protrusion 112 and the second recess 122 in the first embodiment. Please refer to the first embodiment and will not be further described here.

[0100] Optional, please refer to Figure 22 and Figure 23 One of the carpal support 11 and the carpal connector 12 has a limiting boss 128, and the other has a limiting recess 118 that matches the limiting boss 128. The limiting boss 128 is used to snap into the limiting recess 118 to limit the rotation and radial movement of the carpal support 11 relative to the carpal connector 12. Figure 22 and Figure 23 In the illustrated example, the wrist support 11 has a limiting recessed area 118, which is recessed in the wrist support platform 110. The carpal connector 12 has a limiting boss 128, which protrudes toward the wrist support 11. The shape of the limiting boss 128 matches the shape of the limiting recessed area 118. When the wrist support 11 and the carpal connector 12 are assembled and connected, the limiting boss 128 engages with the limiting recessed area 118 and is restricted in its circumferential rotation and radial movement, thereby achieving a reliable connection between the wrist support 11 and the carpal connector 12.

[0101] Furthermore, the carpal support 11 has a tapered protrusion 116, and the carpal connector 12 has a tapered hole 126. When the carpal support 11 and the carpal connector 12 are assembled and connected, the tapered protrusion 116 is inserted into the tapered hole 126, forming a tapered fit, thereby locking the carpal support 11 and the carpal connector 12. In this way, the carpal support 11 and the carpal connector 12 are fixedly connected.

[0102] [Example 5]

[0103] Please refer to Figures 26 to 32 ,in, Figure 26 is a schematic diagram of the assembly of a wrist joint prosthesis according to a fifth embodiment of the present invention; Figure 27 yes Figure 26 The schematic cross-sectional view of the wrist prosthesis shown is along line EE; Figure 28 is a schematic diagram of a wrist support according to a fifth embodiment of the present invention; Figure 29 is a schematic diagram of a wrist bone connector according to a fifth embodiment of the present invention; Figure 30 yes Figure 29 The schematic cross-sectional view of the radial connector along line FF is shown; Figure 31 is a schematic diagram of a radial connector according to a fifth embodiment of the present invention; Figure 32 Schematic diagram of the radial handle according to the fifth embodiment of the present invention.

[0104] The wrist joint prosthesis provided in the fifth embodiment of the present invention is substantially the same as the wrist joint prosthesis provided in the fourth embodiment, and the same parts will not be described again. Only the differences will be described below.

[0105] In the fifth embodiment, the configuration of the carpal connector 12 and the radius connector 22 is different from that in the fourth embodiment. In the fifth embodiment, the first curved surface 120 and the second curved surface 220 are both ellipsoidal surfaces, the first curved surface 120 is concave, and the second curved surface 220 is convex.

[0106] For details, please refer to Figure 29 、 Figure 30 and Figure 31Unlike the fourth embodiment, the first curved surface 120 on the carpal connector 12 is concave, while the second curved surface 220 on the radial connector 22 is convex. When the carpal connector 12 and the radial connector 22 are in contact with each other, they can also rotate relative to the X-axis and the Y-axis. The other structures and configuration principles of this embodiment can be referred to in the fourth embodiment and will not be repeated here.

[0107] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. In addition, the different parts between the various embodiments can also be used in combination with each other, and the present invention is not limited to this.

[0108] In summary, the wrist joint prosthesis provided by the present invention includes: a carpal prosthesis and a radial prosthesis; the carpal prosthesis has a first curved surface, the radial prosthesis has a second curved surface that matches the shape of the first curved surface, the carpal prosthesis and the radial prosthesis are connected to each other along a first direction through the first curved surface and the second curved surface; the carpal prosthesis is configured to be rotatable relative to the radial prosthesis around a second direction and a third direction perpendicular to the first direction, respectively, and the end of the carpal prosthesis for connecting to the carpal bone is rotatable relative to the end of the radial prosthesis for connecting to the radius around the first direction. With such a configuration, by configuring the end for connecting to the carpal bone to be rotatable around the first direction relative to the end of the radial prosthesis for connecting to the radius, the wrist joint prosthesis can realize the circumferential movement function of the radiocarpal joint, improve the patient's wrist joint mobility, and increase patient satisfaction.

[0109] The above description is only a description of the preferred embodiments of the present invention and does not limit the scope of the present invention. Any changes and modifications made by ordinary technicians in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A wrist joint prosthesis, characterized in that: include: A carpal prosthesis and a radial prosthesis; the carpal prosthesis has a first curved surface, the radial prosthesis has a second curved surface that matches the shape of the first curved surface, and the carpal prosthesis and the radial prosthesis are connected by abutting against the first curved surface and the second curved surface along a first direction; The carpal prosthesis is configured to be rotatable relative to the radial prosthesis about a second direction and about a third direction relative to the radial prosthesis; the second direction and the third direction are respectively perpendicular to the first direction; One end of the carpal prosthesis connected to the carpal bone is rotatable around the first direction relative to one end of the radial prosthesis connected to the radius, wherein the carpal prosthesis and the radial prosthesis meet at least one of the following configurations to achieve circumferential movement of the radiocarpal joint; Configuration 1: The carpal prosthesis includes a carpal support and a carpal connector, the carpal support is used to connect to the carpal bone, the first curved surface is located on a side of the carpal connector away from the carpal support, one of the carpal support and the carpal connector has a first protrusion, and the other has a first recess that matches the first protrusion; the first protrusion is used to engage with the first recess, and the first protrusion is rotatable relative to the first recess about the first direction; Configuration 2: The carpal prosthesis includes a carpal support and a carpal connector connected to each other, the first curved surface is located on a side of the carpal connector away from the carpal support, the first curved surface and the second curved surface are both spherical surfaces, and the carpal connector is rotatable relative to the radial prosthesis around the first direction, the second direction, and the third direction respectively due to the abutment between the first curved surface and the second curved surface; Configuration three: The radial prosthesis includes a radial connector and a radial stem connected to each other, the radial stem is used to connect to the radius, the second curved surface is located on the side of the radial connector away from the radial stem, one of the radial connector and the radial stem has a third convex portion, and the other has a third concave portion adapted to the third convex portion; the third convex portion is used to engage with the third concave portion, and the third convex portion is rotatable relative to the third concave portion around the first direction.

2. The wrist joint prosthesis according to claim 1, characterized in that In configuration one, one of the carpal support and the carpal connector has a second protrusion, and the other has a second recess; the second protrusion is configured to abut against and be restricted by the second recess when the rotation angle of the carpal support relative to the carpal connector around the first direction reaches a preset travel range, thereby restricting the rotation angle of the carpal support relative to the carpal connector around the first direction from exceeding the preset travel range.

3. The wrist joint prosthesis according to claim 1, characterized in that In configuration one, the first protrusion and the first recess are both cylindrical, one of the first protrusion and the first recess has a limiting ring arranged around its circumference, and the other has a limiting groove adapted to the limiting ring, and the limiting ring is used to engage with the limiting groove to limit the relative displacement of the first protrusion and the first recess along the axial direction.

4. The wrist joint prosthesis according to claim 1, characterized in that In configuration one, both the first convex portion and the first concave portion include a spherical area, and the spherical area of ​​the first convex portion is adapted to the diameter of the spherical area of ​​the first concave portion, wherein the opening diameter of the spherical area of ​​the first concave portion is smaller than the diameter of the spherical area of ​​the first convex portion, and the spherical area of ​​the first convex portion is used to be engaged with the spherical area of ​​the first concave portion, and then restricted by the spherical area of ​​the first concave portion in displacement along the opening direction.

5. The wrist joint prosthesis according to claim 1, characterized in that In configuration two, the wrist support includes a wrist support platform and two first side wings extending along the second direction. The two first side wings are respectively arranged on both sides of the wrist support platform along the second direction and extend in a direction away from the wrist connector. Each of the first side wings forms an angle of no more than 60° with the wrist support platform.

6. The wrist joint prosthesis according to claim 5, characterized in that: The carpal bone connecting piece includes two second side wings extending along the second direction, and the second side wings are used for being abutted and connected with the first side wings.

7. The wrist joint prosthesis according to claim 5, characterized in that: The wrist bone support and the wrist bone connector are integrally formed.

8. The wrist joint prosthesis according to claim 5, characterized in that: One of the carpal support and the carpal connector has a tapered protrusion, and the other has a tapered hole matched with the tapered protrusion. The carpal support and the carpal connector are detachably connected to the tapered hole through the tapered protrusion.

9. The wrist joint prosthesis according to claim 1, characterized in that: In the configuration 1 or the configuration 2, the wrist bone support has a cancellous nail hole for passing a cancellous bone screw; wherein the diameter of the cancellous nail hole is larger than the diameter of the cancellous bone screw.

10. The wrist joint prosthesis according to claim 1, characterized in that In configuration three, the carpal prosthesis includes a connected carpal support and a carpal connector, the carpal support is used to connect to the carpal bone, the first curved surface is located on the side of the carpal connector away from the carpal support, one of the carpal support and the carpal connector has a limiting boss, and the other has a limiting recessed area adapted to the limiting boss, the limiting boss is used to engage with the limiting recessed area to limit the rotation and radial movement of the carpal support relative to the carpal connector.

11. The wrist joint prosthesis according to claim 1, characterized in that In configuration three, one of the radial connector and the radial stem has a fourth protrusion, and the other has a fourth recess; the fourth protrusion is configured to abut against and be restricted by the fourth recess when the rotation angle of the radial connector relative to the radial stem around the first direction reaches a preset travel range, thereby restricting the rotation angle of the radial connector relative to the radial stem around the first direction from exceeding the preset travel range.

12. The wrist joint prosthesis according to claim 1, characterized in that In the configuration one or the configuration three, the first curved surface and the second curved surface are both ellipsoidal surfaces, and the carpal prosthesis is rotatable relative to the radial prosthesis around the second direction and the third direction respectively due to the abutment between the first curved surface and the second curved surface.

13. The wrist joint prosthesis according to claim 1, characterized in that One of the first curved surface and the second curved surface is a concave surface, and the other is a convex surface.

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