Integrated patient matching type partial femoral head replacement device

Abstract

The invention provides an integrated patient matching type partial femoral head replacement device, and relates to the field of medical instruments. The device comprises a bone nail, an auxiliary fixing piece and a joint prosthesis, the bone nail is provided with a first end part and a second end part nailed into a femoral neck medullary cavity, and the first end part, the auxiliary fixing piece and the joint prosthesis are integrally formed; the auxiliary fixture has a first surface and a second surface in contact with the conical osteotomy femoral head to prevent sinking and lateral rotation. The joint prosthesis only replaces the cut part of the necrotic femoral head, more normal sclerotin can be reserved, trauma is small, femoral head supporting and bearing are not affected or changed, long-term stability of the joint prosthesis is guaranteed, and meanwhile future rebuilding is facilitated. In addition, the first end part, the auxiliary fixing piece and the joint prosthesis are integrally formed, so that joint prosthesis failure caused by looseness or corrosion among the first end part, the auxiliary fixing piece and the joint prosthesis can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to an integrated patient-matched partial femoral head replacement device. Background Art

[0002] Avascular necrosis of femoral head (ANFH), also known as femoral head necrosis, is one of the common orthopedic diseases. It often occurs in patients with previous hip trauma, long-term and large-scale use of glucocorticoids or alcoholism, and can occur at all ages. It occurs in about 800,000 people each year and is the main disease causing disability in young and middle-aged people. The International Association for Osteonecrosis and Bone Microcirculation (ARCO) divides femoral head necrosis into four stages. Stage I: The necrosis area is less than 30%, usually without obvious symptoms, but there is local ischemia. Stage II: The necrosis area is 30%, the femoral head has not collapsed, and there may be slight pain. Stage III: The necrosis area is 30%, the femoral head has collapsed, and the joint pain and stiffness are obvious. Stage IV: The necrosis area is greater than 30%, and the femoral head has severely collapsed. At present, the treatment methods for stage II and stage III femoral head necrosis include hip surface replacement, hemiarthroplasty or total hip replacement.

[0003] Among them, resurfacing removes the entire surface cartilage surface of the femoral head, including the normal part, leaving only a small part of the bone, mainly cancellous bone. In the long term, adverse events such as femoral head prosthesis sinking and prosthesis loosening are frequent. Resurfacing can easily damage the blood supply of the femoral head, leading to secondary necrosis of the femoral head, thus affecting the stability of the prosthesis. Because the diameter of the resurfacing prosthesis is the same as that of the femoral head, and the larger the diameter of the prosthesis, the more obvious the increase in serum metal ion levels after surgery. Many studies have shown that delayed irradiation caused by excessive metal ion concentration may increase the risk of teratogenicity, mutagenicity, and immunodeficiency. These adverse events are closely related to prosthesis structural design defects, surface treatment methods, and material selection.

[0004] In addition, hemiarthroplasty and total hip replacement are traumatic for patients, as the entire femoral head and most of the femoral neck are removed. For young patients with high mobility, the initial stability is poor, the risk is greater, and the cost is high due to the small amount of bone supporting the prosthesis during future revision. Hemiarthroplasty uses the entire metal head to replace the femoral head, which rubs against the physiological acetabular cartilage, easily causing wear and collapse of the acetabular cartilage, increasing the difficulty of acetabular revision during future revision.

[0005] In short, existing treatment methods all have the problems of small bone retention, poor long-term stability, and difficulty in future revision. Summary of the invention

[0006] In order to solve the problems of low bone retention, poor long-term stability and difficulty in future revision in existing treatment methods, the purpose of the present invention is to provide an integrated patient-matched partial femoral head replacement device.

[0007] The present invention provides the following technical solutions: An integrated patient-matched partial femoral head replacement device includes a bone screw, an auxiliary fixation member and a joint prosthesis; The bone nail has a first end and a second end nailed into the medullary cavity of the femoral neck, the auxiliary fixing piece is located on the side of the first end, the joint prosthesis is located at the first end and an end of the auxiliary fixing piece away from the second end, and the first end, the auxiliary fixing piece and the joint prosthesis are integrally formed; The auxiliary fixing piece has a first surface and a second surface in contact with the femoral head after tapered osteotomy, the first surface is located at one end of the auxiliary fixing piece facing the second end portion to prevent sinking, and the second surface is arranged in pairs at both sides of the auxiliary fixing piece along the circumference of the first end portion to prevent lateral rotation; The joint prosthesis is used to replace the resected part of the necrotic femoral head.

[0008] As a further optional solution to the integrated patient-matched partial femoral head replacement device, the diameter of the bone screw is D1, 6mm≤D1≤18mm, so as to adapt to the maximum or minimum diameter size of the femoral neck between different individuals to achieve stable fixation; and / or The length of the bone screw exceeding the auxiliary fixing member is L, 0mm<L≤80mm, so as to provide stable support for osteoporosis patients.

[0009] As a further optional solution to the one-piece patient-matched partial femoral head replacement device, the bone screw is configured in a conical shape, and the cross-sectional area of ​​the first end is larger than the cross-sectional area of ​​the second end.

[0010] As a further optional solution to the integrated patient-matched partial femoral head replacement device, the cone angle of the bone screw is α, 0°<α≤45°.

[0011] As a further optional solution to the one-piece patient-matched partial femoral head replacement device, the bone screw is arranged in a pyramid shape, and the bone screw is suitable for osteoporotic femoral heads; or The bone screw is arranged in a conical shape, and the bone screw is suitable for a femoral head without osteoporosis; or The surface of the bone screw is provided with a plurality of step portions to enhance the anti-pullout performance, and the plurality of step portions are arranged along the length direction of the bone screw.

[0012] As a further optional solution to the integrated patient-matched partial femoral head replacement device, a groove is provided on the surface of the bone screw, and the groove extends along the length direction of the bone screw.

[0013] As a further optional scheme for the integrated patient-matched partial femoral head replacement device, the joint prosthesis has an outwardly convex joint surface, which is located at one end of the joint prosthesis away from the first end portion and the auxiliary fixation device, and a flange is circumferentially arranged at the edge of the joint surface, and the width of the flange increases with the severity of osteoporosis of the femoral head to prevent sinking.

[0014] As a further optional solution to the integrated patient-matched partial femoral head replacement device, the articular surface is a spherical surface, and the diameter of the articular surface is D2, 36mm≤D2≤58mm, so as to match patients of different heights and body shapes; or The joint surface is a non-spherical surface, and the joint surface is formed by simulating a defect death area according to the patient's imaging data. The surface of the joint surface is polished to form a wear-resistant layer.

[0015] As a further optional solution to the one-piece patient-matched partial femoral head replacement device, the area of ​​the articular surface is less than 60% of the surface area of ​​the femoral head.

[0016] The embodiments of the present invention have the following beneficial effects: When using the above-mentioned integrated patient-matched partial femoral head replacement device, the second end of the bone screw is nailed into the femoral neck medullary cavity through the top of the femoral head. Since the first end of the bone screw, the auxiliary fixing piece and the joint prosthesis are integrally formed, the above-mentioned integrated patient-matched partial femoral head replacement device can be fixed on the femoral head after the conical osteotomy. Among them, the first surface of the auxiliary fixing piece contacts the femoral head along the length direction of the bone screw to prevent sinking, and the second surface of the auxiliary fixing piece contacts the femoral head along the circumference of the first end to prevent lateral rotation, so that when the joint prosthesis only replaces the resected part of the necrotic femoral head, it can also ensure sufficient axial and rotational initial stability, and it is not easy to shift during long-term use. On this basis, the joint prosthesis only replaces the resected part of the necrotic femoral head, which is conducive to retaining more normal bone, with less trauma, does not affect and does not change the support and load-bearing capacity of the femoral head, ensures the long-term stability of the joint prosthesis, and is convenient for future renovation. In addition, the first end, the auxiliary fixing piece and the joint prosthesis are integrally formed, which can avoid the failure of the joint prosthesis caused by loosening or corrosion between the first end, the auxiliary fixing piece and the joint prosthesis.

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 The overall structure schematic diagram of an integrated patient-matched partial femoral head replacement device provided by an embodiment of the present invention is shown; Figure 2 A front view of an integrated patient-matched partial femoral head replacement device provided by an embodiment of the present invention is shown; Figure 3 A schematic diagram of the overall structure of an integrated patient-matched partial femoral head replacement device provided by another embodiment of the present invention is shown; Figure 4 A schematic diagram of the overall structure of an integrated patient-matched partial femoral head replacement device provided by another embodiment of the present invention is shown; Figure 5 A schematic diagram of the overall structure of an integrated patient-matched partial femoral head replacement device provided by another embodiment of the present invention is shown; Figure 6 A schematic diagram of the overall structure of an integrated patient-matched partial femoral head replacement device provided by another embodiment of the present invention is shown; Figure 7 A schematic diagram of the overall structure of an integrated patient-matched partial femoral head replacement device provided by another embodiment of the present invention is shown.

[0020] Description of main component symbols: 100 - bone screw; 110 - first end; 120 - second end; 130 - step portion; 140 - groove; 200 - auxiliary fixing member; 210 - first surface; 220 - second surface; 300 - joint prosthesis; 310 - joint surface; 320 - flange. DETAILED DESCRIPTION

[0021] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of the template are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] Example See also Figure 1 The present embodiment provides an integrated patient-matched partial femoral head replacement device, hereinafter referred to as a "femoral head replacement device", which is composed of a bone screw 100, an auxiliary fixing member 200 and a joint prosthesis 300.

[0027] The bone nail 100 has a first end 110 and a second end 120 for nailing into the femoral neck medullary cavity. The auxiliary fixing member 200 is located on the side of the first end 110, and the joint prosthesis 300 is located at one end of the first end 110 and the auxiliary fixing member 200 away from the second end 120, and the first end 110, the auxiliary fixing member 200 and the joint prosthesis 300 are integrally formed.

[0028] The auxiliary fixing member 200 has a first surface 210 and a second surface 220 that contact the femoral head after tapered osteotomy. The first surface 210 is located at one end of the auxiliary fixing member 200 facing the second end 120 to prevent sinking. The second surface 220 is arranged in pairs on both sides of the auxiliary fixing member 200 along the circumference of the first end 110 to prevent lateral rotation.

[0029] In addition, the joint prosthesis 300 is used to replace the resected part of the necrotic femoral head.

[0030] When using the above-mentioned femoral head replacement device, the second end 120 of the bone screw 100 is screwed into the femoral neck medullary cavity through the top of the femoral head. Since the first end 110 of the bone screw 100, the auxiliary fixing member 200 and the joint prosthesis 300 are integrally formed, the above-mentioned femoral head replacement device is fixed on the femoral head after the conical osteotomy. Wherein, the first surface 210 of the auxiliary fixing member 200 contacts the femoral head along the length direction of the bone screw 100 to prevent the above-mentioned femoral head replacement device from sinking, and the second surface 220 of the auxiliary fixing member 200 contacts the femoral head along the circumference of the first end 110 to prevent the above-mentioned femoral head replacement device from rotating laterally, so that when the joint prosthesis 300 only replaces the partially necrotic femoral head that is removed, sufficient axial and rotational initial stability can be guaranteed, and it is not easy to shift during long-term use. On this basis, the joint prosthesis 300 only replaces the partially necrotic femoral head that is removed, which is conducive to retaining more normal bone, with little trauma, does not affect and does not change the femoral head support and load-bearing, ensures the long-term stability of the joint prosthesis 300, and is convenient for future renovation. In addition, the first end portion 110 , the auxiliary fixing member 200 and the joint prosthesis 300 are integrally formed, which can prevent the failure of the joint prosthesis 300 caused by loosening or corrosion between the first end portion 110 , the auxiliary fixing member 200 and the joint prosthesis 300 .

[0031] In some embodiments, the above-mentioned femoral head replacement device is made of metal materials through 3D printing or machining, and the metal materials include but are not limited to zirconium-niobium alloy, cobalt-chromium-molybdenum alloy, alumina-based ceramics or titanium metal.

[0032] Wherein, when the material of the femoral head replacement device is zirconium-niobium alloy, its surface is heat-treated to form a zirconium oxide ceramic interface. Alternatively, when the material of the femoral head replacement device is titanium metal, its surface is surface-treated to form a ceramic interface.

[0033] In other embodiments, the femoral head replacement device can also be made of PAEK (polyetherketoneketone, polyaryletherketone) and its composite materials through 3D printing or machining.

[0034] In some embodiments, the bone interface where the femoral head replacement device contacts the bone adopts a microporous design to form a microporous layer, which is conducive to bone ingrowth, thereby making the joint prosthesis 300 firmly fixed.

[0035] Among them, the porosity of the microporous layer is 30-90%, the pore size is 150-2000 microns, and the connectivity is ≥50%.

[0036] In other embodiments, the bone interface where the femoral head replacement device contacts the bone may also adopt a non-microporous design.

[0037] Please also read Figure 1 and Figure 2 Specifically, the bone screw 100 is conically arranged, extending in a taper from the first end 110 to the second end 120 , and the cross-sectional area of ​​the first end 110 is greater than the cross-sectional area of ​​the second end 120 .

[0038] Depending on the quality of the patient's bone mass, the stability of the femoral head replacement device may be improved by selectively increasing the cone angle design.

[0039] Furthermore, the cone angle of the bone screw 100 is α, satisfying 0°<α≤45°.

[0040] The taper angle of the bone screw 100 specifically refers to the angle between two long sides of the longitudinal section of the bone screw 100 .

[0041] Optionally, the taper angle of the bone screw 100 may be 1°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, or any value between 0° and 45°.

[0042] In some embodiments, the bone screw 100 is configured in a pyramidal shape, and the bone screw 100 is suitable for osteoporotic femoral heads.

[0043] Generally speaking, the patient's bone condition is divided into four levels according to the severity of osteoporosis. Level 1: If the patient's bone density is measured above -1, and the patient does not have symptoms such as low back pain, body pain, etc., it is normal. Level 2: If the measured bone density is between -1 and -2.5, it is called osteopenia, and the patient may have mild low back pain and pain in the bones of the limbs. Level 3: If the measured bone density value is less than -2.5, it is called osteoporosis. Level 4: If the patient's measured bone density value is less than -2.5 and there are brittle fractures in other parts of the body, it is called severe osteoporosis. The more severe the osteoporosis, the less bone retention, the worse the fixation effect of the above-mentioned femoral head replacement device and the bone, and the femoral head replacement device is prone to fixation failure.

[0044] Therefore, for patients with severe osteoporosis (corresponding to the third and fourth grades), the multi-edge design can increase the stability of the bone screw 100 through the edges and corners.

[0045] Exemplarily, the bone screw 100 may be configured in a triangular pyramid shape.

[0046] See also Figure 3 Alternatively, the bone screw 100 may also be configured as a quadrangular pyramid.

[0047] See also Figure 4 Alternatively, the bone screw 100 may also be configured as an irregular pyramid shape, which is not limited in this embodiment.

[0048] See also Figure 5 In other embodiments, a plurality of step portions 130 are provided on the surface of the bone screw 100 to enhance the anti-pullout performance, which is also suitable for patients with severe osteoporosis.

[0049] The plurality of step portions 130 are arranged along the length direction of the bone screw 100 .

[0050] See also Figure 6 In some other embodiments, the bone screw 100 is configured in a conical shape, and the bone screw 100 is suitable for a femoral head that is not osteoporotic (corresponding to the first and second levels).

[0051] For patients with better osteoporosis, the conical fixation can effectively fix the joint prosthesis 300 while increasing bone retention, providing better long-term stability and facilitating future revision.

[0052] See also Figure 7 Taking a conical bone screw 100 as an example, further, a groove 140 is provided on the surface of the bone screw 100 , and the groove 140 extends along the length direction of the bone screw 100 .

[0053] The provision of the groove 140 can further increase the bone retention amount and simultaneously make the bone screw 100 more firmly connected to the femoral neck along the circumferential direction.

[0054] Exemplarily, there are three grooves 140 , which are evenly distributed along the circumference of the bone nail 100 .

[0055] In some embodiments, the diameter of the bone screw 100 is D1, which satisfies 6 mm ≤ D1 ≤ 18 mm, so as to adapt to the maximum or minimum diameter size of the femoral neck between different individuals to achieve stable fixation.

[0056] When in use, according to Chinese anatomical data, the minimum anterior-posterior diameter of the male femoral neck is (26.11±2.74) mm, and the minimum anterior-posterior diameter of the female femoral neck is (23.33±2.33) mm. By designing bone screws 100 diameters that meet different femoral necks and retaining sufficient cortical bone and cancellous bone thickness, the above-mentioned femoral head replacement device can be stably filled and fixed.

[0057] Optionally, the diameter of the bone screw 100 may be 6 mm, 8 mm, 10 mm, 12 mm, 14 mm, 16 mm, 18 mm, or any value between 6 mm and 18 mm.

[0058] Please refer again Figure 2 In some embodiments, the length of the bone screw 100 beyond the auxiliary fixing member 200 is L, which satisfies 0mm<L≤80mm, so as to provide stable support for osteoporosis patients.

[0059] The length of the bone screw 100 beyond the auxiliary fixing member 200 specifically refers to the distance between the end of the second end 120 away from the first end 110 and the first surface 210 along the length direction of the bone screw 100 .

[0060] When in use, the length of the bone screw 100 beyond the auxiliary fixing member 200 is designed according to the quality of the patient's bone. The longer the length of the bone screw 100 beyond the auxiliary fixing member 200 is, the more stable support can be provided, ensuring that the joint prosthesis 300 is stably fixed in the femoral neck.

[0061] Optionally, the length of the bone screw 100 beyond the auxiliary fixing member 200 may be 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm or any value between 0 mm and 80 mm.

[0062] Please refer again Figure 1 In some embodiments, the joint prosthesis 300 has a convex joint surface 310. The joint surface 310 is located at one end of the joint prosthesis 300 away from the first end 110 and the auxiliary fixing member 200, and a flange 320 is circumferentially arranged at the edge of the joint surface 310.

[0063] On the one hand, the flange 320 can increase the contact area between the joint surface 310 and the bone surface. On the other hand, the flange 320 can effectively support the joint prosthesis 300, so that the joint prosthesis 300 does not sink after implantation, and prevents the appearance of steps.

[0064] The width of the flange 320 increases with the severity of osteoporosis of the femoral head. That is, for patients with more severe osteoporosis, the size of the flange 320 can be increased to more effectively prevent the above-mentioned femoral head replacement device from sinking.

[0065] In this embodiment, the width of the flange 320 is no greater than 4 mm.

[0066] Optionally, the width of the flange 320 may be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, or any value between 0 mm and 4 mm.

[0067] Exemplarily, the articular surface 310 is a spherical surface, and the diameter of the articular surface 310 is D2, which satisfies 36 mm ≤ D2 ≤ 58 mm, so as to match patients of different heights and body shapes. When in use, articular surfaces 310 of different diameters are set to match patients of different heights and body shapes. In addition, the angle of the articular surface 310 is 90°-180°, and each interval of 1° is a specification, so as to increase the patient matching degree.

[0068] Optionally, the diameter of the articular surface 310 can be 36 mm, 38 mm, 40 mm, 42 mm, 44 mm, 46 mm, 48 mm, 50 mm, 52 mm, 54 mm, 56 mm, 58 mm, or any value between 36 mm and 58 mm.

[0069] Alternatively, the articular surface 310 may also be a non-spherical surface, and the articular surface 310 is formed by simulating the defective dead area according to the patient's imaging data. When in use, the three-dimensional model is first reconstructed according to the patient's imaging data, and then the outer dimensions of the articular surface 310 are reconstructed according to the defective dead area of ​​the femoral head to achieve individual customization, ensure that the joint prosthesis 300 is smoothly connected to the bone surface retained by the femoral head, avoid the formation of high and low steps between the articular surface 310 and the retained bone surface, and thus reduce wear.

[0070] In addition, the surface of the joint surface 310 is polished to form a wear-resistant layer, making it more wear-resistant.

[0071] In some embodiments, the area of ​​the articular surface 310 is less than 60% of the surface area of ​​the femoral head.

[0072] Specifically, the femoral head replacement device only replaces the necrotic part of the femoral head surface, retaining part of the femoral head bone, ensuring that the joint prosthesis 300 and the residual bone tissue can be stably fixed. When in use, the matching joint surface 310 is designed according to the stage diagnosis of femoral head necrosis and the necrotic area.

[0073] In summary, the above-mentioned femoral head replacement device is based on the surgical theory of partial femoral head replacement, adopts a matching structural design, only replaces the necrotic area, retains most of the original femoral head bone, and ensures the stability of the joint prosthesis 300. In the future, when renovating, the doctor can still use traditional surface replacement, hemi-hip replacement or total hip replacement to achieve step-by-step treatment of femoral head necrosis, which is more conducive to maintaining the patient's long-term good joint function. In addition, the above-mentioned femoral head replacement device adopts an integrated design to avoid the risk of connection failure between split components.

[0074] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0075] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0076] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An integrated patient-matched partial femoral head replacement device, characterized in that: Including bone screws, auxiliary fixation parts and joint prostheses; The bone nail has a first end and a second end nailed into the medullary cavity of the femoral neck, the auxiliary fixing piece is located on the side of the first end, the joint prosthesis is located at the first end and an end of the auxiliary fixing piece away from the second end, and the first end, the auxiliary fixing piece and the joint prosthesis are integrally formed; The auxiliary fixing piece has a first surface and a second surface in contact with the femoral head after tapered osteotomy, the first surface is located at one end of the auxiliary fixing piece facing the second end portion to prevent sinking, and the second surface is arranged in pairs at both sides of the auxiliary fixing piece along the circumference of the first end portion to prevent lateral rotation; The joint prosthesis is used to replace the resected part of the necrotic femoral head.

2. The one-piece patient-matched partial femoral head replacement device according to claim 1, characterized in that: The diameter of the bone screw is D1, 6mm≤D1≤18mm, so as to adapt to the maximum or minimum diameter of the femoral neck between different individuals to achieve stable fixation; and / or The length of the bone screw exceeding the auxiliary fixing member is L, 0mm<L≤80mm, so as to provide stable support for osteoporosis patients.

3. The one-piece patient-matched partial femoral head replacement device according to claim 2, characterized in that: The bone screw is arranged in a conical shape, and the cross-sectional area of ​​the first end is larger than the cross-sectional area of ​​the second end.

4. The one-piece patient-matched partial femoral head replacement device according to claim 3, characterized in that: The cone angle of the bone screw is α, 0°<α≤45°.

5. The one-piece patient-matched partial femoral head replacement device according to any one of claims 1 to 4, characterized in that: The bone screw is arranged in a pyramid shape and is suitable for osteoporotic femoral heads; or The bone screw is arranged in a conical shape and is suitable for the femoral head without osteoporosis; or The surface of the bone screw is provided with a plurality of step portions to enhance the anti-pullout performance, and the plurality of step portions are arranged along the length direction of the bone screw.

6. The one-piece patient-matched partial femoral head replacement device according to claim 5, characterized in that: A groove is arranged on the surface of the bone screw, and the groove extends along the length direction of the bone screw.

7. The one-piece patient-matched partial femoral head replacement device according to any one of claims 1 to 4, characterized in that: The joint prosthesis has an outwardly convex joint surface, which is located at one end of the joint prosthesis away from the first end and the auxiliary fixing member. A flange is circumferentially arranged at the edge of the joint surface, and the width of the flange increases with the severity of osteoporosis of the femoral head to prevent sinking.

8. The one-piece patient-matched partial femoral head replacement device according to claim 7, characterized in that: The articular surface is a spherical surface, and the diameter of the articular surface is D2, 36mm≤D2≤58mm, so as to match patients of different heights and body shapes; or The joint surface is a non-spherical surface, and the joint surface is formed by simulating a defect death area according to the patient's imaging data. The surface of the joint surface is polished to form a wear-resistant layer.

9. The one-piece patient-matched partial femoral head replacement device according to claim 8, characterized in that: The area of ​​the articular surface is less than 60% of the surface area of ​​the femoral head.

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