Assembled radial head prosthesis

Abstract

The invention provides an assembled radial head prosthesis, and belongs to the technical field of medical instruments. The invention provides an assembled radial head prosthesis which comprises a radial head, a radial handle and a plurality of sets of filling parts, a joint nest is formed in the upper end of the radial head, and a mounting groove is formed in the lower end of the radial head; a mounting head is arranged at the upper end of the radial handle and is arranged in the mounting groove; the multiple sets of filling parts are sequentially arranged in a stacked mode and all arranged on the outer side of the radial handle in a sleeving mode, the inner side walls of the filling parts are matched with the outer side wall of the radial handle in shape, and the filling part at the lowermost end is located above the osteotomy bone surface of the radius of the patient. According to the assembled radial head prosthesis, the number of the filling pieces is selected according to the actual situation, the filling pieces are arranged between the radial head and the osteotomy bone surface of a patient, the osteotomy bone surface is supported, the position of the radial head is limited, the stability of the prosthesis after implantation is improved, and the risks that the prosthesis is loosened and fractures occur around the prosthesis are reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, and particularly relates to a modular radial head prosthesis. BACKGROUND

[0002] Clinically, radial head fractures caused by trauma, elbow instability, cubitus varus deformity, and humeroradial arthritis can be treated by radial head arthroplasty. The essence of radial head arthroplasty is to reconstruct the original anatomical structure of the head. It restores the integrity of the radial head and neck and the normal function of the elbow joint by replacing the damaged radial head with an artificial prosthesis or using internal fixation devices.

[0003] The anatomical structure of the radial head is very complex, and there are also great differences between different individuals. During the radial head arthroplasty procedure, the radial head is exposed through a lateral incision, a micro swing saw is used to perform radial head osteotomy at the radial neck, the proximal radial medullary cavity is expanded to complete the anatomical matching of the prosthesis, and then a prosthesis template is inserted. After confirming the size of the radial head prosthesis, an appropriate size prosthesis is selected, and the complexity of forearm and elbow joint movement determines that the radial head prosthesis replacement must achieve accurate matching of the prosthesis and the affected elbow.

[0004] Due to the wear and tear of the prosthesis during use, and the influence of the matching degree of the prosthesis and the patient, the postoperative stability of the prosthesis after installation in the joint is poor, and the prosthesis is prone to looseness in the medullary cavity, which is not conducive to the recovery of joint function in patients. SUMMARY

[0005] The purpose of the present application is to provide a modular radial head prosthesis to solve the problem of loosening of the radial head prosthesis during use, which affects the recovery of the patient.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present application is to provide a modular radial head prosthesis, comprising: a radial head, an upper end of which is provided with a joint socket, and a lower end of which is provided with a mounting slot;

[0007] a radial stem, an upper end of which is provided with a mounting head, the mounting head being arranged in the mounting slot; and

[0008] a plurality of filler pieces arranged in sequence and sleeved on the outer side of the radial stem, the inner side wall of the filler piece being matched in shape with the outer side wall of the radial stem, wherein the lowermost filler piece is located above the osteotomy bone surface of the patient's radius.

[0009] In one possible implementation, the outer side of the radial stem is sleeved with a blocking piece, the blocking piece being arranged below the plurality of filler pieces, and the blocking piece being used to limit the downward displacement of the filler pieces.

[0010] In a possible implementation, the blocking piece comprises a blocking block and a blocking ring, the inner side wall of the blocking block is shaped to match the outer side wall of the radius stem, an annular groove is arranged on the inner side wall of the blocking block, the blocking ring is arranged in the annular groove, the blocking ring is an open ring, the inner side wall of the annular groove is a tapered surface, the height of the annular groove is greater than the height of the blocking ring, the inner diameter of the annular groove gradually increases from top to bottom, and the blocking ring tightly embraces the radius stem when the blocking ring moves to the upper end of the annular groove.

[0011] In a possible implementation, a positioning sheet is arranged below the annular groove, and the blocking ring is arranged above the positioning sheet, the positioning sheet being used to limit the blocking ring.

[0012] In a possible implementation, the outer side wall of the blocking ring is a tapered surface, and the outer diameter of the blocking ring gradually increases from top to bottom, the inner side wall of the annular groove matches the outer side wall of the blocking ring.

[0013] In a possible implementation, a plurality of groups of the filling pieces, wherein at least two groups of the filling pieces are wedge-shaped filling pieces, and the remaining filling pieces are columnar filling pieces, the upper and lower end faces of the wedge-shaped filling pieces are arranged at an angle, and the upper and lower end faces of the columnar filling pieces are arranged in parallel.

[0014] In a possible implementation, a suture hole is arranged on the filling piece, and the suture hole penetrates through the filling piece.

[0015] In a possible implementation, the outer side wall of the radius stem is provided with an anti-rotation limiting surface.

[0016] In a possible implementation, a plurality of locking hole groups are arranged at the lower end of the radius stem.

[0017] In a possible implementation, a first positioning line is arranged on the side wall of the radius head, a second positioning line is arranged on the side wall of the mounting head, and the first positioning line and the second positioning line are arranged in the same plane.

[0018] The assembled radius head prosthesis has the following advantages:

[0019] Compared with the prior art, the radius head imitates the real physiological curve, the joint socket arranged on the upper end face of the radius head is used to match the humerus of the patient, the adaptability of the prosthesis to the bone structure of the patient during use is increased, the comfort of the patient is improved, and the damage of the prosthesis to the bone of the patient is reduced.

[0020] The radial head and the radial stem are designed in a split mode, the mounting head at the upper end of the radial stem matches the mounting groove at the lower end of the radial head, the mounting head is mounted in the mounting groove, the radial head and the radial stem are fixed, and the stability of the device implanted in the body of a patient is increased.

[0021] A plurality of filling members are sequentially sleeved on the outer side of the radial stem from top to bottom, the filling members are provided with through holes, the side walls of the through holes match the shape of the outer side wall of the radial stem, the filling members are conveniently sleeved on the radial stem, the filling members can be selected and matched according to actual conditions, are suitable for different conditions of different patients, adapt to various intraoperative conditions, the lowermost filling member is located above the radial osteotomy bone surface, can effectively support the prosthesis, avoids subsidence of the prosthesis during use, reduces the possibility of axial shaking of the radial stem during the recovery process of the patient, avoids extrusion of the radial stem on the radial canal wall of the patient, reduces the possibility of loosening of the prosthesis after implantation, improves the stability of the prosthesis after implantation, the filling members are sleeved on the outer side of the radial stem, the strength of the radial stem is strengthened, and the risk of fracture around the prosthesis is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0023] Figure 1 The implantation state diagram of the assembled radial head prosthesis provided by the embodiment of the present application is shown.

[0024] Figure 2 The three-dimensional structure diagram of the assembled radial head prosthesis provided by the embodiment of the present application is shown. Figure 1 ;

[0025] Figure 3 The three-dimensional structure diagram of the assembled radial head prosthesis provided by the embodiment of the present application is shown. Figure 2 ;

[0026] Figure 4 The exploded structure diagram of the radial head and the radial stem used in the embodiment of the present application is shown.

[0027] Figure 5 The three-dimensional structure diagram of the blocking member used in the embodiment of the present application is shown.

[0028] Figure 6 The exploded structure diagram of the blocking member used in the embodiment of the present application is shown.

[0029] Figure 7This is a vertical sectional view of the blocking component used in the embodiments of the present invention;

[0030] Figure 8 This is a vertical cross-sectional view of the blocking block used in an embodiment of the present invention;

[0031] Figure 9 This is a schematic diagram of the implantation status of the modular radial head prosthesis provided in an embodiment of the present invention. Figure 2 .

[0032] In the diagram: 100, radial head; 101, articular fossa; 102, mounting groove; 103, first positioning line; 200, radial stem; 201, mounting head; 202, second positioning line; 203, upper stem; 204, lower stem; 205, anti-rotation limiting surface; 206, first locking hole; 207, second locking hole; 300, filler; 301, wedge-shaped filler; 302, cylindrical filler; 303, suture hole; 400, blocking element; 401, blocking block; 402, annular groove; 403, positioning groove; 404, positioning piece; 405, blocking ring; 500, radius. Detailed Implementation

[0033] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0034] This invention provides a modular radial head prosthesis, please refer to... Figures 1 to 4 as well as Figure 9 The radial head 100 has an arc-shaped sidewall, mimicking the real physiological curve. The shape and setting of the articular socket 101 conform to the physiological structure. The articular socket 101 set on the upper end face of the radial head 100 matches the patient's humerus, increasing the adaptability of the prosthesis to the patient's bone structure during use, improving the patient's comfort, and reducing damage between the prosthesis and the patient's bones.

[0035] The shape of the radial stem 200 conforms to the physiological structure of the human body. The radial stem 200 includes an upper stem portion 203 and a lower stem portion 204. The lower end of the upper stem portion 203 is connected to the upper end of the lower stem portion 204. The mounting head 201 is located at the upper end of the upper stem portion 203. The lower end face of the mounting head 201 is set at an angle with the upper stem portion 203. The length of the upper stem portion 203 is less than that of the lower stem portion 204. The lower stem portion 204 is used to insert into the medullary cavity of the radius 500 of the patient. The upper stem portion 203 and the lower stem portion 204 are set at an angle. The upper stem portion 203 and the lower stem portion 204 are connected by an arc transition, which helps to reduce stimulation to surrounding tissues and is more in line with the characteristics of the physiological structure of the human body.

[0036] The mounting head 201 is in the shape of a circular truncated cone, the side wall of the mounting head 201 is a conical surface, the diameter of the upper end of the mounting head 201 is smaller than the diameter of the lower end of the mounting head 201, the included angle between the side wall of the mounting head 201 and the lower end surface of the mounting head 201 is less than 90° and greater than 87°, the inner side wall of the mounting groove 102 matches the outer surface of the mounting head 201, and the mounting groove 102 and the mounting head 201 can be in interference fit to increase the stability of the mounting of the mounting head 201.

[0037] The radius head 100 and the radius stem 200 are designed in two parts, the mounting head 201 at the upper end of the radius stem 200 is mounted in the mounting groove 102 at the lower end of the radius head 100, and the radius head 100 and the radius stem 200 are fixed, which increases the stability of the device implanted in the patient's body.

[0038] The outer side wall of the filler 300 can be surrounded by a circular arc surface, a flat surface, or a combination of a circular arc surface and a flat surface. Preferably, the cross-section of the filler 300 in the horizontal direction is circular or elliptical, and the outer side wall of the filler 300 is a circular arc surface, which helps to reduce the stimulation to the surrounding tissues and better conforms to the physiological structure of the human body.

[0039] Please refer to Figure 9 The outer side wall of the filler 300 can be anatomical, conforming to the physiological curve of the human body and increasing the adaptability of the human body.

[0040] The filler 300 is provided in the form of a tessellation polygon structure, which has the following advantages:

[0041] a. Good biocompatibility: The tessellation polygon porous structure can accurately control the size, shape and connectivity of the pores through 3D printing technology, which can simulate the structure of human cancellous bone and provide a good microenvironment for the adhesion, proliferation and differentiation of bone cells;

[0042] b. Promote cell growth: The porous characteristics of the tessellation polygon porous structure provide sufficient space and nutrient exchange channels for cells, which is beneficial for cell migration, growth and tissue formation in the pores;

[0043] c. Excellent bone integration ability: The tessellation polygon porous structure has good bone conduction, which can guide the growth of bone tissue along the pores and promote the close combination of the implant and the surrounding bone tissue, achieving bone integration;

[0044] d. Uniform stress transmission: The tessellation polygon porous structure can simulate the mechanical properties of bone tissue to some extent, with an elastic modulus close to that of human bone, achieving uniform stress transmission between the implant and the surrounding bone tissue, avoiding stress shielding effect (stress shielding can cause bone absorption and bone loss), which helps to maintain the normal physiological function of bone tissue and promote long-term stability of bone integration.

[0045] The contact surfaces of the two groups of fillers 300 adjacent to each other in the length direction of the radius stem 200 are consistent in shape, which helps to increase the stability of the fillers 300 during use of the prosthesis, and the outer side walls of the multiple groups of fillers 300 together present a smooth circular arc surface, which helps to reduce the stimulation to the surrounding tissues and is more in line with the physiological structure characteristics of the human body.

[0046] The fillers 300 are sleeved on the outer side of the radius stem 200, the through holes provided on the fillers 300 are provided through the upper and lower end surfaces of the fillers 300, and the side walls of the through holes are matched in shape with the outer side walls of the radius stem 200, so that the fillers 300 are easily sleeved on the radius stem 200.

[0047] During use of the device, the radius 500 is cut according to the fracture splitting degree / bone defect degree / bone tumor degree of the proximal end of the radius 500 of the patient to obtain a cut bone surface of the radius 500, the cut bone surface is a plane, and the number of fillers 300 required to be installed is determined according to the length of the cut. The mounting head 201 is installed in the mounting groove 102, the required number of fillers 300 are installed from the lower end of the radius stem 200, the fillers 300 are moved to the uppermost position of the radius stem 200, and the fillers 300 are sequentially stacked from top to bottom. After the installation of the fillers 300 is completed, the lower end of the radius stem 200 is inserted into the medullary cavity of the radius 500 of the patient from the cut bone surface, the radius stem 200 gradually extends into the medullary cavity of the radius 500 of the patient, and the lowermost filler 300 abuts against the cut bone surface.

[0048] The fillers 300 can be selected and matched according to actual conditions, are suitable for different conditions of different patients, and adapt to various intraoperative surgical conditions. The fillers 300 abut against the cut bone surface, which can effectively support the prosthesis, avoid subsidence of the prosthesis during use, reduce the possibility of loosening of the prosthesis after implantation, and improve the stability of the prosthesis after implantation. The fillers 300 are sleeved on the outer side of the radius stem 200, which strengthens the strength of the radius stem 200 and reduces the risk of fracture around the prosthesis.

[0049] As a specific embodiment of the assembled radius head prosthesis provided by the application, please refer to Figures 1 to 8 The outer side of the radius stem 200 is sleeved with a blocking piece 400, the blocking piece 400 is arranged below the lowermost filler 300, and the blocking piece 400 is used to limit the downward displacement of the filler 300.

[0050] Please refer to Figures 1 to 8The blocking piece 400 is sleeved on the outer side of the radius stem 200, is arranged between the filling piece 300 and the bone surface of the radius 500, and is installed on the radius stem 200 from the lower end of the radius stem 200 after the filling piece 300 on the radius stem 200 is installed to the required number, and the upper end surface of the blocking piece 400 abuts against the lower end surface of the lowermost filling piece 300.

[0051] The blocking piece 400 is provided with a one-way structure, which limits the movement direction of the blocking piece 400, that is, the blocking piece 400 can move from the lower end to the upper end on the radius stem 200, and cannot move from the upper end to the lower end, the blocking piece 400 limits the downward displacement of the filling piece 300, and the blocking piece 400 can exert a pressing force on the filling piece 300 above the blocking piece 400 to eliminate the gap between the filling pieces 300.

[0052] The blocking piece 400 can be effectively positioned on the radius stem 200, so that the filling piece 300 and the blocking piece 400 do not displace after the prosthesis is assembled, the filling piece 300 and the blocking piece 400 do not displace during implantation, the implantation operation of the prosthesis is not affected, the difficulty of implantation of the prosthesis is reduced, and the accuracy and stability of implantation of the prosthesis are improved.

[0053] When the prosthesis is implanted into the intramedullary cavity of the radius 500 of the patient, the lower end surface of the blocking piece 400 abuts against the bone surface of the radius 500, the blocking piece 400 directly contacts the bone surface, and has a mutual force, and the blocking piece 400 can stably abut against the bone surface.

[0054] The blocking piece 400 and the filling piece 300 can effectively generate a supporting force on the radial head 100, so that the prosthesis does not sink during use, the possibility of loosening of the prosthesis is reduced, the stability of use of the prosthesis is improved, the use time of the prosthesis is prolonged, and the revision process of the prosthesis is delayed.

[0055] As a specific embodiment of the assembled radius head prosthesis provided by the application, please refer to Figures 5 to 8 The blocking piece 400 comprises a blocking block 401 and a blocking ring 405, the inner side wall of the blocking block 401 is matched with the outer side wall of the radius stem 200 in shape, the inner side wall of the blocking block 401 is provided with an annular groove 402, the blocking ring 405 is arranged in the annular groove 402, the blocking ring 405 is an open ring, the inner side wall of the annular groove 402 is a tapered surface, the height of the annular groove 402 is greater than the height of the blocking ring 405, the inner diameter of the annular groove 402 gradually increases from top to bottom, and the blocking ring 405 tightly holds the radius stem 200 when the blocking ring 405 moves to the upper end of the annular groove 402.

[0056] The upper end surface of the blocking block 401 is parallel to the lower end surface, and the side wall of the blocking block 401 is perpendicular to the upper end surface, the lower end surface of the blocking block 401 is parallel to the osteotomy surface of the radius 500 of the patient, and the lower end surface of the blocking block 401 is perpendicular to the radius stem 200 at the position of the blocking block 401, and a clearance hole is arranged at the center of the blocking block 401, which is suitable for the radius stem 200 to pass through.

[0057] The one-way structure in the blocking piece 400 is an annular groove 402 and a blocking ring 405. The annular groove 402 is arranged on the side wall of the clearance hole, and the annular groove 402 is arranged along the circumference of the clearance hole, and the blocking ring 405 is arranged in the annular groove 402. The blocking block 401 and the blocking ring 405 are combined into an integral whole, and when the blocking piece 400 is sleeved outside the radius stem 200, the blocking ring 405 is also sleeved outside the radius stem 200.

[0058] The outer diameter of the lower end surface of the annular groove 402 is greater than the outer diameter of the upper end surface, and the distance from the upper end surface of the positioning piece 404 to the uppermost end of the annular groove 402 is greater than the height of the blocking ring 405, that is, when the lower end of the blocking ring 405 abuts against the positioning piece 404, there is a gap between the upper end of the blocking ring 405 and the upper top wall of the annular groove 402, and the blocking ring 405 has the freedom to move up and down in the annular groove 402.

[0059] An opening is arranged on the blocking ring 405, and the blocking ring 405 is easy to change shape and reduce in diameter under pressure.

[0060] The blocking ring 405 is a polygon, and the side wall of the radius stem 200 is a special-shaped surface, which improves the matching degree of the blocking ring 405 and the radius stem 200.

[0061] The annular groove 402 is arranged in the lower half of the clearance hole, and the side wall of the upper half of the clearance hole matches the side wall of the radius stem 200, which facilitates the sleeving of the blocking block 401 on the radius stem 200.

[0062] In the initial state, the positioning piece 404 and the blocking ring 405 are in interference fit, that is, at this time, the blocking ring 405 has downward pressure on the positioning piece 404, and the positioning piece 404 exerts a certain upward force on the blocking ring 405, and the positioning piece 404 has a pre-added force on the blocking ring 405.

[0063] When the blocking piece 400 is installed, the blocking piece 400 is sleeved outside the radius stem 200 and moves from bottom to top, at this time, a friction force is generated between the radius stem 200 and the blocking ring 405, under the action of the friction force, the blocking ring 405 is subjected to a downward force, the positioning piece 404 blocks the blocking ring 405, the friction force and the supporting force of the positioning piece 404 to the blocking ring 405 are counteracted, the blocking ring 405 is located at the lower end of the annular groove 402, the inner diameter of the lower end of the annular groove 402 is larger than that of the upper end, the inner diameter of the blocking ring 405 is in a larger state, the blocking ring 405 exerts a smaller force on the radius stem 200, that is, at this time, the blocking block 401 can be pushed upward.

[0064] When the blocking block 401 is installed to a specified position, a certain upward force is continuously applied to the blocking block 401, the blocking piece 400 can exert a pre-pressing force on the filler 300 to eliminate the gap between the filler 300; the upward pushing force on the blocking block 401 is cancelled, at this time, under the action of the self-gravity of the blocking block 401 and the pre-pressing force applied during installation, the blocking block 401 has a downward moving force, at this time, a friction force is generated between the radius stem 200 and the blocking ring 405, under the action of the friction force, the blocking ring 405 is subjected to an upward force, the blocking ring 405 moves upward relative to the blocking block 401, because the blocking ring 405 has an opening, as the inner diameter of the annular groove 402 gradually decreases, the inner diameter of the blocking ring 405 gradually decreases, the blocking ring 405 exerts a gradually increasing force on the radius stem 200, the friction force between the blocking ring 405 and the radius stem 200 gradually increases, until the friction force and the downward force it receives are balanced, the blocking ring 405 tightly holds the radius stem 200, and the limiting of the blocking piece 400 and the filler 300 is realized.

[0065] As a specific embodiment of the assembled radius head prosthesis provided by the application, please refer to Figures 5 to 8 , the lower portion of the annular groove 402 is provided with the positioning piece 404, and the blocking ring 405 is arranged above the positioning piece 404, and the positioning piece 404 is used for limiting the blocking ring 405.

[0066] As a specific embodiment, please refer to Figures 5 to 8 , the positioning piece 404 is arranged below the annular groove 402, and the positioning piece 404 is arranged parallel to the lower end surface of the blocking block 401.

[0067] The positioning piece 404 is provided with a plurality of groups, and optionally, the positioning piece 404 is provided with three groups, and the three groups of positioning pieces 404 are uniformly distributed along the circumference of the annular groove 402.

[0068] The side wall of the accommodating hole is provided with a positioning groove 403, the positioning groove 403 is arranged along the circumference of the accommodating hole, the positioning groove 403 is arranged below the annular groove 402, and the inner diameter of the positioning groove 403 is greater than that of the annular groove 402.

[0069] The first end of the positioning piece 404 is arranged on the side wall of the positioning groove 403, the second end of the positioning piece 404 penetrates into the accommodating hole, and the diameter of the circle where the second ends of the plurality of groups of positioning pieces 404 are located is smaller than the inner diameter of the lower end of the annular groove 402.

[0070] After the blocking ring 405 is installed in the annular groove 402, the second end of the positioning piece 404 can limit the blocking ring 405, so that the blocking ring 405 is prevented from falling out of the annular groove 402.

[0071] As a specific embodiment of the assembly type radius head prosthesis provided by the application, please refer to Figures 5 to 8 The outer side wall of the blocking ring 405 is a tapered surface, the outer diameter of the blocking ring 405 gradually increases from top to bottom, and the inner side wall of the annular groove 402 is matched with the outer side wall of the blocking ring 405.

[0072] The outer diameter of the lower end surface of the blocking ring 405 is greater than that of the upper end surface, and the inclination of the side wall of the blocking ring 405 is consistent with that of the side wall of the annular groove 402, so that the blocking ring 405 can move up and down in the annular groove 402.

[0073] As a specific embodiment of the assembly type radius head prosthesis provided by the application, please refer to Figures 1 to 4 Among the plurality of filling pieces 300, at least two groups of filling pieces 300 are wedge-shaped filling pieces 301, and the remaining filling pieces 300 are columnar filling pieces 302; the planes where the upper and lower end surfaces of the wedge-shaped filling pieces 301 are located are arranged at an angle, and the upper and lower end surfaces of the columnar filling pieces 302 are arranged in parallel.

[0074] As a specific embodiment, please refer to Figures 1 to 4 The filling pieces 300 can be divided into two types, i.e., the wedge-shaped filling pieces 301 and the columnar filling pieces 302.

[0075] The upper and lower end surfaces of the columnar filling piece 302 are parallel, and the columnar filling piece 302 is suitable for being installed on the outer side of the upper handle 203 or the lower handle 204; the upper end surface of the columnar filling piece 302 on the outer side of the upper handle 203 is perpendicular to the upper handle 203, and the upper end surface of the columnar filling piece 302 on the outer side of the lower handle 204 is perpendicular to the lower handle 204.

[0076] The upper and lower end surfaces of the wedge-shaped filling piece 301 are not parallel to each other, and the wedge-shaped filling piece 301 is suitable for being installed on the outer side of the circular arc transition between the upper handle 203 and the lower handle 204.

[0077] Further, the wedge-shaped filler 301 can be provided with two groups, the upper end surface of the upper wedge-shaped filler 301 is perpendicular to the upper handle 203, and the lower end surface of the lower wedge-shaped filler 301 is perpendicular to the lower handle 204, and the lower end surface of the upper wedge-shaped filler 301 overlaps the upper end surface of the lower wedge-shaped filler 301.

[0078] The outer side wall of the wedge-shaped filler 301 and the cylindrical filler 302 is smooth and arc-shaped, which forms a smooth transition and helps to reduce the stimulation to the surrounding tissue and conforms to the physiological structure of the human body.

[0079] Further, the mounting head 201 and the upper handle 203 are arranged at an angle, the uppermost filler 300 of the upper handle 203 is a wedge-shaped filler 301, the upper end surface of the wedge-shaped filler 301 is attached to the lower end surface of the mounting head 201, and the lower end surface of the wedge-shaped filler 301 is perpendicular to the upper handle 203.

[0080] According to the above arrangement rule, the wedge-shaped filler 301 and the cylindrical filler 302 are arranged and installed, and the wedge-shaped filler 301 and the cylindrical filler 302 are closely stacked on the radius handle 200, which increases the stability of the prosthesis during use.

[0081] As a specific embodiment of the assembled radius head prosthesis provided by the present application, please refer to Figures 1 to 4 The filler 300 is provided with a suture hole 303, and the suture hole 303 penetrates the filler 300.

[0082] The wedge-shaped filler 301 and the cylindrical filler 302 can be provided with a suture hole 303, and the wedge-shaped filler 301 and the cylindrical filler 302 can not be provided with a suture hole 303.

[0083] One filler 300 can be provided with a group of suture holes 303, and the suture holes 303 penetrate the front and rear walls of the side wall of the filler 300, and the suture holes 303 are located on the side of the radius handle 200.

[0084] One filler 300 can be provided with two groups of suture holes 303, and the two groups of suture holes 303 on the same filler 300 are parallel to each other, and the two groups of suture holes 303 are located on both sides of the radius handle 200.

[0085] During the operation, the surgical suture is used to suture the tendon, the suture hole 303 is suitable for the penetration of the surgical suture, the surgical suture is fixed, the stability of the prosthesis after being implanted into the radius 500 is increased, which helps to restore the physiological structure around the radius 500, promotes the recovery of the patient, and accelerates the rehabilitation process of the patient.

[0086] Combined with Figures 1 to 4The cylindrical filler 302 outside the lower end of the upper handle 203 is provided with a suture hole 303, the wedge-shaped filler 301 at the circular arc transition between the upper handle 203 and the lower handle 204 is provided with a suture hole 303, and the cylindrical filler 302 outside the lower handle 204 is provided with a suture hole 303.

[0087] The same side suture holes 303 on the filler 300 outside the upper handle 203 and the lower handle 204 are distributed on a fitting line similar to the curve of the side wall of the radius handle.

[0088] As a specific embodiment of the assembled radius head prosthesis provided by the application, please refer to Figures 1 to 4 The outer side wall of the radius handle 200 is provided with an anti-rotation limiting surface 205.

[0089] The anti-rotation limiting surface 205 is arranged along the length direction of the radius handle 200, under the action of the anti-rotation limiting surface 205, the side wall of the through hole of the filler 300 matches the outer side wall of the radius handle 200, the anti-rotation limiting surface 205 avoids rotation of the filler 300 in the use process, and the stability of fixation of the filler 300 is increased.

[0090] The anti-rotation limiting surface 205 is provided with two groups, which are arranged on both sides of the radius handle, and the anti-rotation limiting surface 205 can be symmetrically arranged.

[0091] The anti-rotation limiting surface 205 can be an arc surface recessed towards the inside of the radius handle 200, the edge of the anti-rotation limiting surface 205 adopts a circular arc transition, which is convenient for inserting the radius handle 200 into the medullary cavity, helps to reduce the stimulation to the surrounding tissues, is more in line with the physiological structure characteristics of the human body, and is convenient for installation of the filler 300 and the blocking piece 400.

[0092] The width of the anti-rotation limiting surface 205 gradually decreases as it gradually approaches the lower end of the radius handle 200, until it is reduced to zero, that is, the lowermost end of the anti-rotation limiting surface 205 is located above the lowermost end of the radius handle 200.

[0093] As a specific embodiment of the assembled radius head prosthesis provided by the application, please refer to Figures 1 to 4 The lower end of the radius handle 200 is provided with a locking hole group.

[0094] The locking hole group includes a first locking hole 206 and a second locking hole 207, the first locking hole 206 is arranged obliquely above the second locking hole 207, the first locking hole 206 is a circular hole, the second locking hole 207 is an oblong hole, the first locking hole 206 and the second locking hole 207 are both arranged on the radius handle 200 between the two groups of anti-rotation limiting surfaces 205, and the center line of the first locking hole 206 is not parallel to the center line of the second locking hole 207.

[0095] The first locking hole 206 and the second locking hole 207 are suitable for locking the penetration of the locking pin, the locking pin is arranged through the radius 500, the first locking hole 206 / second locking hole 207, and the stability of the prosthesis fixed in the patient's body is increased.

[0096] As a specific embodiment of the assembly type radius head prosthesis provided by the application, please refer to Figure 4 The side wall of the radius head 100 is provided with a first positioning line 103, and the side wall of the mounting head 201 is provided with a second positioning line 202, and the first positioning line 103 and the second positioning line 202 are located in the same plane.

[0097] The first positioning line 103 is vertically arranged along the side wall of the radius head 100, and the second positioning line 202 is vertically arranged along the side wall of the mounting head 201, when the mounting head 201 is mounted on the radius head 100, the lower end of the first positioning line 103 coincides with the upper end of the second positioning line 202, the mounting head 201 is mounted in the mounting groove 102 along the direction of the second positioning line 202, and the accuracy of the mounting of the radius stem 200 is improved.

[0098] The above is only a preferred embodiment of the application, and is not used to limit the application, any modification, equivalent replacement and improvement made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A modular radial head prosthesis, characterized in that, include: The radial head has a joint socket at the upper end and a mounting groove at the lower end; The radial stem has a mounting head at its upper end, and the mounting head is disposed in the mounting groove. as well as Multiple sets of fillers are stacked sequentially and all fitted onto the outer side of the radial stem. The inner sidewall of the filler matches the shape of the outer sidewall of the radial stem. The lowermost filler is located above the osteotomy surface of the patient's radius.

2. The modular radial head prosthesis as described in claim 1, characterized in that, A blocking member is sleeved on the outer side of the radial stem. The blocking member is located below the multiple sets of filling members and is used to restrict the downward displacement of the filling members.

3. A modular radial head prosthesis as described in claim 2, characterized in that, The blocking component includes a blocking block and a blocking ring. The inner sidewall of the blocking block matches the shape of the outer sidewall of the radial stem. An annular groove is provided on the inner sidewall of the blocking block. The blocking ring is disposed in the annular groove. The blocking ring is an open ring. The inner sidewall of the annular groove is a conical surface. The height of the annular groove is greater than the height of the blocking ring. The inner diameter of the annular groove gradually increases from top to bottom. When the blocking ring moves to the upper end of the annular groove, the blocking ring grips the radial stem.

4. A modular radial head prosthesis as described in claim 3, characterized in that, A positioning plate is provided below the annular groove, and a blocking ring is provided above the positioning plate. The positioning plate is used to limit the blocking ring.

5. A modular radial head prosthesis as described in claim 3, characterized in that, The outer wall of the blocking ring is a tapered surface, and the outer diameter of the blocking ring gradually increases from top to bottom. The inner wall of the annular groove matches the outer wall of the blocking ring.

6. A modular radial head prosthesis as described in claim 1, characterized in that, Of the multiple sets of fillers, at least two sets of fillers are wedge-shaped fillers, and the remaining fillers are cylindrical fillers; the planes containing the upper and lower end faces of the wedge-shaped fillers are set at an angle, and the upper and lower end faces of the cylindrical fillers are set parallel to each other.

7. A modular radial head prosthesis as described in claim 1, characterized in that, The filler is provided with a suture hole, which is provided through the filler.

8. A modular radial head prosthesis as described in claim 1, characterized in that, The outer wall of the radial stem is provided with an anti-rotation limiting surface.

9. A modular radial head prosthesis as described in claim 1, characterized in that, The lower end of the radial stem is provided with a locking hole group.

10. A modular radial head prosthesis as described in claim 1, characterized in that, The radial head has a first positioning line on its sidewall, and the mounting head has a second positioning line on its sidewall. The first positioning line and the second positioning line are located in the same plane.

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