Proximal tibial space-occupying prosthesis and preparation method thereof

Abstract

The present invention discloses a proximal tibial space-occupying prosthesis and a preparation method thereof, which belongs to the field of medical device technology. The proximal tibial space-occupying prosthesis of the present invention comprises a proximal tibial prosthesis and a tibial forming mold. The proximal tibial prosthesis is adaptively connected to the tibial forming mold, and the tibial forming mold is used to prepare the proximal tibial prosthesis; the proximal tibial prosthesis comprises a tibial support prosthesis, a tibial shaft prosthesis and a medullary needle. The tibial support prosthesis is arranged at the bottom of the tibial shaft prosthesis, the medullary needle is arranged at the upper part of the tibial shaft prosthesis, and a limiting portion is provided on the proximal tibial prosthesis, which can limit the axial and circumferential displacement of the tibial support prosthesis and the medullary needle; the tibial forming mold comprises a forming portion, and a forming space adapted to the proximal tibial prosthesis is provided in the forming portion. The present invention has a simple structure, the proximal tibial prosthesis is prepared by the tibial forming mold, the prosthesis achieves ideal precision, and the prosthesis is matched and connected with the distal tibia retained by the patient, and can adapt to the patient's knee joint physiological structure to achieve a space-occupying effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and more specifically, relates to a proximal tibial space-occupying prosthesis and a preparation method thereof. Background Art

[0002] Customized tumor prostheses and subsequent replacement have become an important method for functional reconstruction after bone tumor resection during limb-sparing surgery. For proximal tibial tumors, the following prosthetic replacement treatments are available: First, the proximal tibia is resected, and a customized metal tibial prosthesis is directly inserted and fixed to the distal tibia; second, the entire knee joint is replaced with a hinged knee.

[0003] For minors, although the above method can achieve a short-term replacement effect, since the bones have not yet grown and formed, there are various hidden dangers in adopting a one-step prosthesis replacement method, which can easily lead to adverse consequences such as a significant difference in the length of the two legs and high prosthesis costs. Summary of the Invention

[0004] The present invention aims to solve the technical problems existing in the prior art and provides a proximal tibial space-occupying prosthesis and a preparation method thereof.

[0005] In order to solve the above technical problems, the present invention first provides a proximal tibial space-occupying prosthesis, comprising a proximal tibial prosthesis and a tibial forming mold, wherein the proximal tibial prosthesis is adaptively connected to the tibial forming mold, and the tibial forming mold is used to prepare the proximal tibial prosthesis;

[0006] The proximal tibial prosthesis includes a tibial tray prosthesis, a tibial shaft prosthesis and a medullary pin. The tibial tray prosthesis is arranged at the bottom of the tibial shaft prosthesis, and the medullary pin is arranged at the upper part of the tibial shaft prosthesis. A limiter is provided on the proximal tibial prosthesis to limit the axial and circumferential displacement of the tibial tray prosthesis and the medullary pin.

[0007] The tibial forming mold comprises a forming part, wherein a forming space adapted to the proximal tibial prosthesis is provided in the forming part.

[0008] Preferably, the lower end surface of the tibial tray prosthesis is a highly polished articular surface that matches the physiological structure of the patient's joint. The upper end of the tibial tray prosthesis is provided with an anti-rotation connection portion connected to the tibial stem prosthesis and an anti-retraction portion that prevents the tibial stem prosthesis from falling out.

[0009] Preferably, the anti-rotation connection portion includes at least two fixing bosses provided on the upper end of the tibial tray prosthesis, and the anti-recession portion is an anti-recession groove provided on the fixing bosses, and the anti-recession groove is provided along the circumference of the fixing bosses.

[0010] Preferably, a positioning structure is provided in the middle of the medullary needle, which is connected to the tibial stem prosthesis and the upper end of the forming part. The medullary needle is arranged along the axial direction of the tibial stem prosthesis, and the medullary needle below the positioning structure is arranged in the forming part.

[0011] Preferably, the tibial stem prosthesis is made of bone cement material, the positioning structure is provided with an exhaust structure, and the part of the medullary pin located in the tibial stem prosthesis is provided with an anti-retraction structure and an anti-rotation structure.

[0012] Preferably, the shaping part includes a tibial shaft shaping mold, which is a prosthesis shaping part composed of a plurality of split molds, a partition is provided between every two adjacent split molds, and the plurality of split molds are detachably connected.

[0013] Preferably, the tibial forming mold also includes a tibial support positioning base, which is provided with a limiting groove, and the limiting groove includes a first limiting portion and a second limiting portion. The tibial support positioning base is adaptively connected to the lower end of the tibial shaft forming mold through the first limiting portion, and the interior of the tibial shaft forming mold is connected to the second limiting portion, and the tibial support prosthesis is arranged in the second limiting portion.

[0014] Preferably, the upper end portion of the tibial shaft forming mold is provided with a positioning portion, the positioning portion is connected to the medullary pin, and the lower end portion of the medullary pin is arranged in the forming space inside the tibial shaft forming mold.

[0015] The present invention also provides a method for preparing a proximal tibial space-occupying prosthesis, and the preparation method comprises the following steps:

[0016] S1. Based on the patient's CT data, the tibial shaft molding mold and tibial tray positioning base are formed by 3D printing to make them consistent with the natural bone physiological structure;

[0017] S2. Place the tibial tray positioning base on the support surface, and then place the tibial tray prosthesis in the second limiting portion of the tibial tray positioning base;

[0018] S3, sequentially arranging and splicing the multiple sub-molds constituting the tibial shaft forming mold, and inserting them into the first limiting portion of the tibial tray positioning base;

[0019] S4, fixing the tibial tray positioning base to the tibial shaft forming mold through the connecting portion, and assembling the molds into a 3D printed tibial forming mold;

[0020] S5, injecting the prepared bone cement into the tibial forming mold, inserting the medullary needle into the positioning portion of the tibial shaft forming mold before the bone cement solidifies, and then waiting for the bone cement to solidify and form;

[0021] S6. Remove the connection portion of the tibial tray positioning base and knock off the tibial tray positioning base;

[0022] S7. Knock down the sub-mold structures of the tibial shaft forming mold along the partition between the sub-molds, remove the completed mold, and obtain the proximal tibial space-occupying prosthesis.

[0023] Preferably, the tibial tray prosthesis is made of cobalt-chromium-molybdenum material, the medullary pin is made of titanium alloy or cobalt-chromium-molybdenum material, and the size of the proximal tibial space-occupying prosthesis is 5% to 10% smaller than the patient's natural bone.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention has a simple structure. The proximal tibial prosthesis is prepared through a tibial forming mold. The proximal tibial prosthesis achieves ideal precision, and the prosthesis is connected to the distal tibia retained by the patient, and can adapt to the patient's knee joint physiological structure. The prepared prosthesis is a prosthetic structure that matches the patient's bone tissue prepared by 3D printing based on the patient's CT data, achieving an excellent space-occupying effect and meeting the patient's knee joint movement function. The proximal tibial prosthesis is prepared and formed in the molding space of the tibial forming mold, which is simple to operate and reduces the difficulty and cost of the patient's secondary surgery. The proximal tibial prosthesis is provided with a limiting portion, which can limit the axial and circumferential displacement of the tibial support prosthesis and medullary pin, play a role in preventing retreat and avoiding axial shaking, further improving the prosthesis space-occupying effect, and is suitable for situations where the bone has not grown and formed and a large area of ​​infection or tumor occurs in the proximal tibia or platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the proximal tibial space-occupying prosthesis of the present invention;

[0028] Figure 2 Schematic diagram of the structure of the proximal tibial prosthesis of an embodiment of the proximal tibial space-occupying prosthesis of the present invention;

[0029] Figure 3 Schematic diagram of the structure of the tibial stem prosthesis of an embodiment of the proximal tibial space-occupying prosthesis of the present invention;

[0030] Figure 4 This is a schematic structural diagram of a tibial tray prosthesis of an embodiment of a proximal tibial space-occupying prosthesis of the present invention;

[0031] Figure 5 Schematic diagram of the structure of the medullary pin of the proximal tibial space-occupying prosthesis embodiment of the present invention;

[0032] Figure 6 Schematic diagram of the structure of the tibial shaft forming mold of an embodiment of the proximal tibial space-occupying prosthesis of the present invention;

[0033] Figure 7 This is a schematic structural diagram of a tibial forming mold of an embodiment of a proximal tibial space-occupying prosthesis of the present invention;

[0034] Figure 8 This is a schematic structural diagram of the tibial tray positioning base of an embodiment of the proximal tibial space-occupying prosthesis of the present invention.

[0035] Explanation of symbols in the figure:

[0036] 1. Proximal tibial prosthesis; 2. Tibial forming mold; 3. Tibial tray prosthesis; 31. Articular surface; 32. Fixing boss; 33. Anti-retraction groove; 4. Tibial shaft prosthesis; 5. Medullary pin; 51. Positioning ring; 52. Exhaust hole; 53. Anti-retraction boss; 54. Anti-rotation groove; 6. Forming part; 61. Tibial shaft forming mold; 62. Threaded hole; 63. Separation groove; 64. Positioning groove; 7. Tibial tray positioning base; 71. Countersunk hole; 72. First limiting groove; 73. Second limiting groove; 8. Connecting part. DETAILED DESCRIPTION

[0037] To make the technical problems, technical solutions, and beneficial effects to be solved by this application more clearly understood, the following, in conjunction with the accompanying drawings and embodiments, further describes in detail a proximal tibial space-occupying prosthesis and its preparation method provided by this application. It should be understood that the specific embodiments described herein are merely intended to explain this application and are not intended to limit this application.

[0038] See also Figure 1 , which is a schematic structural diagram of a proximal tibial space-occupying prosthesis provided by an embodiment of the invention, comprising a proximal tibial prosthesis 1 and a tibial forming mold 2, wherein the proximal tibial prosthesis 1 is adapted to be connected to the tibial forming mold 2, and the tibial forming mold 2 is used to prepare the proximal tibial prosthesis 1;

[0039] The proximal tibial prosthesis 1 includes a tibial tray prosthesis 3, a tibial shaft prosthesis 4 and a medullary pin 5. The tibial tray prosthesis 3 is arranged at the bottom of the tibial shaft prosthesis 4, and the medullary pin 5 is arranged at the upper part of the tibial shaft prosthesis 4. A limiting portion is provided on the proximal tibial prosthesis 1, which can limit the axial and circumferential displacement of the tibial tray prosthesis 3 and the medullary pin 5.

[0040] The tibial forming mold 2 includes a forming portion 6 , within which is a forming space adapted to the proximal tibial prosthesis 1 .

[0041] The present invention has a simple structure. The proximal tibial prosthesis 1 is prepared by a tibial forming mold 2. The proximal tibial prosthesis 1 achieves ideal precision, and the prosthesis is connected to the distal tibia retained by the patient, and can adapt to the patient's knee joint physiological structure. Moreover, the prepared prosthesis is a prosthetic structure that matches the patient's bone tissue prepared by 3D printing based on the patient's CT data, achieving an excellent space-occupying effect and meeting the patient's knee joint movement function. The proximal tibial prosthesis 1 is prepared and formed in the forming space of the tibial forming mold 2, which is simple to operate and reduces the difficulty and cost of the patient's secondary surgery. In addition, a limiting portion is provided on the proximal tibial prosthesis 1, which can limit the axial and circumferential displacement of the tibial support prosthesis 3 and the medullary needle 5, thereby preventing retreat and avoiding axial shaking, further improving the prosthesis space-occupying effect, and is suitable for situations where the bone has not grown and formed and a large area of ​​infection or tumor occurs at the proximal tibia or platform.

[0042] In this embodiment, Figure 1-Figure 3 As shown, the proximal tibial prosthesis 1 is formed by pouring bone cement into the tibial forming mold 2, and the tibial support prosthesis 3 and the medullary needle 5 are connected to the tibial forming mold 2 respectively. The tibial shaft prosthesis 4 is made of bone cement material, and the tibial shaft prosthesis 4 is prepared by mold pouring, so that the tibial support prosthesis 3 and the medullary needle 5 are firmly connected to the tibial shaft prosthesis 4 respectively, forming the proximal tibial prosthesis 1 for use in tibial surgery.

[0043] Specifically, such as Figure 4 As shown, the tibial tray prosthesis 3 is a bone tray structure as a whole, and the lower end surface of the tibial tray prosthesis 3 is a highly polished articular surface. After the high-polishing treatment, the articular surface 31 is not only smooth and wear-resistant, but also the material used to make it has excellent strength and hardness. The articular surface 31 is compatible with the physiological structure of the patient's joint. The upper end surface of the tibial tray prosthesis 3 is provided with an anti-rotation connection portion connected to the tibial shaft prosthesis 4 and an anti-retraction portion to prevent the tibial shaft prosthesis 4 from falling out.

[0044] In this embodiment, the anti-rotation connection portion is two fixed bosses 32 arranged on the upper end surface of the tibial support prosthesis 3. The fixed bosses 32 are arranged vertically, and the two fixed bosses 32 are arranged parallel to each other at the left and right ends of the upper end surface of the tibial support prosthesis 3. The fixed bosses 32 are irregular structures with a circular cross-section. By setting two fixed bosses 32, relative rotation of the tibial shaft prosthesis 4 after casting can be prevented, thereby affecting stability.

[0045] The anti-retreat portion is arranged on the fixed boss 32, and the anti-retreat portion is an anti-retreat groove 33 arranged in the middle of the fixed boss 32. The anti-retreat grooves 33 are evenly distributed along the circumference of the fixed boss 32, so that the fixed boss 32 is a coupled frustum structure. The middle size of the fixed boss 32 is smaller than the size at both ends. The anti-retreat groove 33 and the peripheral structure form a snap-fit ​​structure, thereby effectively preventing the tibial support prosthesis 3 from falling off the tibial shaft prosthesis 4, so that the tibial shaft prosthesis 4 is firmly connected to the tibial support prosthesis 3.

[0046] Furthermore, in this embodiment, the tibial support prosthesis 3 is machined from cobalt-chromium-molybdenum material. Cobalt-chromium-molybdenum (CoCrMo) is a high-performance alloy material composed of elements such as cobalt, chromium, and molybdenum. It has excellent corrosion resistance, high-temperature strength, and wear resistance. At high temperatures, the strength and hardness of the alloy can remain stable, and plastic deformation or brittle fracture will not occur. At the same time, the cobalt-chromium-molybdenum material has excellent corrosion resistance and can resist the erosion of various corrosive media such as acids, alkalis, and salts. It has high durability, stable performance, and long service life; the high-polished joint surface at the bottom is adaptively connected to the tibial forming mold 2, and the fixed boss 32 set at the top as an anti-rotation connection part is not limited to the fixed number and structure, and the number can be set to two or more. The cross-section of the fixed boss 32 can be set to an elliptical, arc-shaped or square structure as needed, which can ensure that the tibial support prosthesis 3 and the tibial shaft prosthesis 4 do not rotate relative to each other.

[0047] Furthermore, both the tibial support prosthesis 3 and the tibial shaft prosthesis 4 can be customized according to the patient's joint CT data to meet the patient's physiological structure and achieve a perfect fit. The axial length of the tibial shaft prosthesis 4 meets the patient's physiological structure and can be set to 50-100 mm, or the corresponding size of the tibial forming mold 2 can be adjusted as needed to adjust the various sizes of the tibial shaft prosthesis 4 to achieve the best space-occupying effect.

[0048] like Figure 5 As shown, in this embodiment, the medullary needle 5 is a long-rod needle-shaped structure, which plays the role of initially fixing the prosthesis when casting the tibial stem prosthesis 4; the medullary needle 5 is arranged along the axial direction of the tibial stem prosthesis 4, and a positioning structure is provided in the middle of the medullary needle 5. The medullary needle 5 can be inserted into the tibial stem forming mold 61, and the insertion depth of the medullary needle 5 is ensured by the positioning structure. The positioning structure is connected to the tibial stem prosthesis 4 and is connected to the upper end of the forming part 6. The medullary needle structure at the lower part of the positioning structure is arranged on the inner side of the forming part, and the medullary needle structure at the upper part of the positioning structure is arranged on the outer side of the forming part 6.

[0049] Specifically, the positioning structure is a positioning ring 51 protruding along the circumference of the medullary needle 5. The positioning ring 51 is connected to the upper end of the forming part 6. The positioning ring 51 is a circular ring structure, and the inner end side is tightly connected to the outer circumference of the medullary needle 5. The positioning ring 51 is provided with an upper circular ring end face and a lower circular ring end face. The positioning ring 51 is provided with an exhaust structure. The exhaust structure ensures that bubbles and excess bone cement in the bone cement can be discharged when pouring bone cement. The exhaust structure includes three exhaust holes 52. The exhaust holes 52 are vertically arranged along the axial direction of the positioning ring 51 and pass through the upper circular ring surface and the lower circular ring surface of the positioning ring 51. The three exhaust holes 52 are evenly distributed along the circumference of the positioning ring 51.

[0050] In this embodiment, the medullary needle 5 located at the bottom of the positioning ring 51 is provided with an anti-retraction structure and an anti-rotation structure. The medullary needle 5 at the bottom of the positioning ring 51 is connected to the tibial shaft prosthesis 4. The anti-retraction structure and the anti-rotation structure play a role in preventing retreat and avoiding axial shaking, thereby ensuring the stability of the connection between the medullary needle 5 and the tibial shaft prosthesis 4.

[0051] Specifically, the anti-retraction structure is an anti-retraction boss 53 arranged on the medullary needle 5. The anti-retraction boss 53 is an outward convex structure. The left and right sides of the anti-retraction boss 53 are respectively protruded outward along the radial direction of the medullary needle 5. There are multiple anti-retraction bosses 53 arranged along the axial direction of the medullary needle 5. The anti-retraction bosses 53 prevent the medullary needle 5 from falling out of the tibial stem prosthesis 4 made of bone cement; the anti-rotation structure is arranged on the anti-retraction boss 53, and the anti-rotation structure includes an anti-rotation groove 54. The anti-rotation groove 54 is arranged in the groove area between the protruding structures on both sides of the anti-retraction boss 53. The number and shape of the anti-rotation grooves 54 are adapted to the number and internal shape of the anti-retraction bosses 53. By setting the anti-rotation grooves 54, the medullary needle 5 can be prevented from rotating in the tibial stem prosthesis 4.

[0052] Furthermore, as a preferred embodiment of the present invention, the medullary needle 5 can be made of titanium alloy or cobalt-chromium-molybdenum material. The conventional length of the medullary needle 5 is 40 to 120 mm, and its setting length can also be customized according to the length of the patient's residual natural bone. The specific number and shape of the anti-retraction structure and anti-rotation structure set on the medullary needle 5 can be adapted and adjusted as needed, and are not limited to square or arc structures.

[0053] like Figure 6 、 Figure 7 As shown, in this embodiment, the forming portion 6 includes a tibial shaft forming mold 61, which is a component of the 3D printing mold. The tibial shaft forming mold 61 has an internal space, which is the casting space for the tibial shaft prosthesis 4. The tibial shaft forming mold 61 is a prosthesis forming portion composed of multiple sub-molds, with a separator between each two adjacent sub-molds, and the multiple sub-molds are detachably connected. The use of a split sub-mold structure not only facilitates installation and connection, but also facilitates demolding after bone cement pouring.

[0054] Specifically, the tibial shaft forming mold 61 is vertically arranged, and the tibial shaft forming mold 61 is composed of four vertically arranged sub-molds spliced ​​together, and the tibial shaft forming mold 61 can be arranged into a left-right symmetrical structure, and each sub-mold is provided with a threaded hole 62 arranged along the axial direction at the bottom. After the four sub-molds are closed, a partition is provided between each two adjacent sub-molds, and the partition is a provided partition groove 63. The inner circumferential sides of each two adjacent sub-molds are fitted and connected to each other, and the partition groove 63 is provided at the adjacent outer ends. The provided partition groove 63 facilitates the separation of the tibial shaft prosthesis 4 from the tibial shaft forming mold 61 during demolding.

[0055] In this embodiment, a positioning portion is provided at the upper end of the tibial shaft forming mold 61 , and the positioning portion is connected to the medullary needle 5 . The lower end of the medullary needle 5 is disposed in the forming space inside the tibial shaft forming mold 61 .

[0056] Specifically, the positioning portion includes a positioning groove 64, which is arranged in the middle of the upper end of the tibial shaft forming mold 61 and at the upper end opening of the casting space inside the tibial shaft forming mold 61. The positioning groove 64 is a circular structure and the size and shape of the positioning groove 64 are adapted to the size and shape of the positioning ring 51 on the medullary needle 5, so as to facilitate precise positioning of the medullary needle 5 when inserted. The lower end of the positioning groove 64 is provided with an annular support surface, which is convenient for supporting the lower circular end face of the positioning ring 51 when the medullary needle 5 is inserted.

[0057] Furthermore, in this embodiment, the diameter of the positioning groove 64 is slightly larger than the outer diameter of the positioning ring 51 , thereby facilitating the insertion and removal of the positioning ring 51 .

[0058] like Figure 7 、 Figure 8 As shown, in this embodiment, the tibial forming mold 2 also includes a tibial tray positioning base 7, the upper end of which is connected to the tibial shaft forming mold 61, together forming the tibial prosthesis forming mold. The tibial tray positioning base 7 has a circular support structure on its periphery and a limiting groove on its inner side for limiting support. The tibial tray positioning base 7 has a forming mold support surface on its inner side, and four countersunk holes 71 are provided at the four corners of the forming mold support surface. The size and position of the countersunk holes 71 are arranged relative to the threaded holes 62 at the lower end of the tibial shaft forming mold 61.

[0059] Specifically, the limiting groove includes a first limiting portion and a second limiting portion, the first limiting portion includes a first limiting groove 72, and the second limiting portion includes a second limiting groove 73. The tibial support positioning base 7 is adaptively connected to the lower end of the tibial shaft forming mold 61 through the first limiting groove 72, and the internal space of the tibial shaft forming mold 61 is connected to the second limiting groove 73, and the tibial support prosthesis 3 is arranged in the second limiting groove 73.

[0060] In this embodiment, the first limiting groove 72 is a circular-segmented structure and is adapted to the outer peripheral shape of the tibial shaft forming mold 61, ensuring a stable connection between the bottom end of the tibial shaft forming mold 61 and the limiting groove of the tibial tray positioning base 7, and the connection setting mode of one-end plane and three-end curved surfaces realizes a rapid positioning connection between the tibial shaft forming mold 61 and the tibial tray positioning base 7. When the tibial shaft forming mold 61 is connected to the tibial tray positioning base 7, the threaded hole 62 of the tibial shaft forming mold 61 at the upper end is matched with the countersunk hole 71 of the tibial tray positioning base 7 at the lower end through the connecting portion 8. The connecting portion 8 can be a vertically arranged connecting bolt or connecting pin structure, and then the tibial shaft forming mold 61 is firmly plugged and connected to the tibial tray positioning base 7 through the connecting portion 8 to prevent position displacement.

[0061] Furthermore, a second limiting groove 73 is provided on the inner bottom surface of the tibial tray positioning base 7 , and the second limiting groove 73 is adaptively connected to the bottom articular surface 31 of the tibial tray prosthesis 3 .

[0062] In this embodiment, the tibial shaft forming mold 61 and the tibial tray positioning base 7 are customized according to the patient's CT data and formed by 3D printing. The first limiting groove 72 set on the inner side of the tibial tray positioning base 7 is slightly larger than the outer peripheral size of the tibial shaft forming mold 61, and the second limiting groove 73 is slightly larger than the articular surface 31 of the tibial tray prosthesis 3, thereby facilitating the insertion and removal of the connecting parts.

[0063] In this embodiment, the overall structure of the proximal tibial prosthesis 1, except for the contact surface between the distal end and the natural bone, is designed according to the CT data of the patient's bone joints, thereby maintaining consistency with the physiological structure of the natural bone. At the same time, the original size is reduced by 5% to 10% compared with the natural bone. The reduced size is conducive to better coordination with the original muscle tissue and prevents the prosthesis from being too protruding and causing the overall size to be too large. By pouring bone cement into the tibial forming mold 2, the bone cement is dried and solidified to form the tibial shaft prosthesis 4, which is connected together with the tibial support prosthesis 3 and the medullary needle 5 to form a complete proximal tibial prosthesis 1, so that the final prosthesis has a physiological structure that matches the patient's original tissue and achieves excellent biological properties.

[0064] Moreover, the present invention has a simple structure. The proximal tibial prosthesis 1 is prepared by a tibial forming mold 2. The proximal tibial prosthesis 1 achieves ideal precision, and the prosthesis is matched and connected with the distal tibia retained by the patient, and can adapt to the patient's knee joint physiological structure. In addition, the prepared prosthesis is a prosthetic structure that matches the patient's bone tissue prepared by 3D printing based on the patient's CT data, achieving an excellent space-occupying effect, satisfying the patient's knee joint activity function, increasing their sense of well-being, and realizing the "space-occupying" function, reducing the difficulty and cost of the patient's secondary surgery.

[0065] Furthermore, the present invention also provides a method for preparing a proximal tibial space-occupying prosthesis, and the preparation method comprises the following steps:

[0066] S1. Based on the patient's CT data, the tibial shaft forming mold 61 and the tibial tray positioning base 7 are formed by 3D printing to make them consistent with the natural bone physiological structure;

[0067] S2. Place the tibial tray positioning base 7 on the support surface, then place the tibial tray prosthesis 3 in the second limiting groove 73 of the tibial tray positioning base 7, and connect the tibial tray prosthesis 3 to the tibial tray positioning base 7;

[0068] S3, arranging and splicing the four sub-molds constituting the tibial shaft forming mold 61 in sequence, aligning and placing them, and inserting them into the first limiting groove 72 of the tibial tray positioning base 7, thereby firmly connecting the tibial shaft forming mold 61 to the tibial tray positioning base 7;

[0069] S4. Align the threaded hole 62 with the countersunk hole 71, and then fix and adapt the tibial tray positioning base 7 to the tibial shaft forming mold 61 through the connecting portion 8, and assemble the molds into a 3D printed tibial forming mold 2;

[0070] S5, inject the modulated bone cement into the tibial forming mold 2, and before it solidifies, insert the medullary needle 5 into the positioning groove 64 of the tibial shaft forming mold 61, and then wait for the bone cement to solidify and form;

[0071] S6. After the bone cement is solidified, remove the connecting portion 8 of the tibial tray positioning base 7 and gently knock down the tibial tray positioning base 7.

[0072] S7. Knock down the sub-mold structures of the tibial shaft forming mold 61 along the separation grooves 63 between the sub-molds, remove the completed mold, and obtain the final proximal tibial space-occupying prosthesis.

[0073] The present invention provides a proximal tibial space-occupying prosthesis with a simple structure, formed by pouring bone cement through a 3D printing mold, and a preparation method thereof, wherein the tibial shaft prosthesis 4 is molded by pouring bone cement, which has a simple process and low cost, can not only achieve a normal supporting role, but also avoid soft tissue adhesion, reduce the difficulty of secondary surgery, and the secondary surgery is simple to operate and can achieve a good space-occupying effect; and the articular surface of the tibial support prosthesis 3 is made of cobalt-chromium-molybdenum material and is highly polished to make the articular surface smooth and wear-resistant, achieving excellent biological functions and performance; and the medullary pin adopts a bone cement type fixation method, with anti-retreat and anti-rotation grooves on the surface, which play a role in preventing retreat and avoiding axial shaking. The present invention as a whole is based on the patient's CT data, through the perfect combination of 3D printing and machining, so that the final molded prosthesis has a physiological structure that matches the patient's original tissue, meets the patient's knee joint activity function, increases their sense of well-being, and can also achieve the "space-occupying" function, reducing the difficulty and cost of the patient's secondary surgery.

[0074] The proximal tibial prosthesis 1 of the present invention is prepared by a tibial forming mold 2. The proximal tibial prosthesis 1 achieves ideal precision, and the prosthesis is matched and connected with the patient's retained distal tibia, can adapt to the patient's knee joint physiological structure, and is prepared by 3D printing based on the patient's CT data to match the patient's bone tissue, thereby achieving an excellent space-occupying effect and satisfying the patient's knee joint activity function; the proximal tibial space-occupying prosthesis is prepared and formed in the forming space of the tibial forming mold 2, which is simple to operate and reduces the difficulty and cost of the patient's secondary surgery. In addition, the proximal tibial prosthesis is provided with a limiting portion, an anti-rotation portion and other structures, which can limit the axial and circumferential displacement of the tibial support prosthesis and medullary needle through the limiting portion, play a role in preventing retreat and avoiding axial shaking, ensure the stability of the tibial shaft prosthesis during casting, further provide a prosthesis space-occupying effect, avoid the hidden dangers of adopting a one-step prosthesis replacement method, and is suitable for situations where the bone has not grown and is fixed and a large area of ​​infection or tumor occurs at the proximal tibia or platform.

[0075] In the description of the present invention, it should be understood that the orientations or positional relationships indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", and "outside" are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0076] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0077] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A proximal tibial space-occupying prosthesis, comprising a proximal tibial prosthesis and a tibial forming mold, characterized in that: The proximal tibial prosthesis is adaptively connected to the tibial forming mold, and the tibial forming mold is used to prepare the proximal tibial prosthesis; The proximal tibial prosthesis includes a tibial support prosthesis, a tibial shaft prosthesis and a medullary needle, the tibial support prosthesis is arranged at the bottom of the tibial shaft prosthesis, the medullary needle is arranged at the upper part of the tibial shaft prosthesis, and the proximal tibial prosthesis is provided with a limiting portion, which can limit the axial and circumferential displacement of the tibial support prosthesis and the medullary needle; the tibial forming mold includes a forming portion, and a forming space adapted to the proximal tibial prosthesis is provided in the forming portion; a positioning structure is provided in the middle part of the medullary needle, the positioning structure is connected to the tibial shaft prosthesis and connected to the upper end part of the forming portion, the medullary needle is arranged along the axial direction of the tibial shaft prosthesis, and the medullary needle at the lower part of the positioning structure is arranged in the forming portion; the tibial shaft prosthesis is made of bone cement material, the positioning structure is provided with an exhaust structure, and the part of the medullary needle located in the tibial shaft prosthesis is provided with an anti-retreat structure and an anti-rotation structure.

2. The proximal tibial space-occupying prosthesis according to claim 1, characterized in that: The lower end surface of the tibial tray prosthesis is a highly polished articular surface, which is adapted to the physiological structure of the patient's joint. The upper end of the tibial tray prosthesis is provided with an anti-rotation connection portion connected to the tibial stem prosthesis and an anti-retraction portion to prevent the tibial stem prosthesis from falling out.

3. The proximal tibial space-occupying prosthesis according to claim 2, characterized in that: The anti-rotation connection portion includes at least two fixing bosses arranged at the upper end of the tibial tray prosthesis, and the anti-recession portion is an anti-recession groove arranged on the fixing bosses, and the anti-recession groove is arranged along the circumference of the fixing bosses.

4. A proximal tibial space-occupying prosthesis according to any one of claims 1 to 3, characterized in that: The forming part comprises a tibial shaft forming mold, which is a prosthesis forming part composed of a plurality of split molds. A partition is provided between every two adjacently connected split molds, and the plurality of split molds are detachably connected.

5. The proximal tibial space-occupying prosthesis according to claim 4, characterized in that: The tibial forming mold also includes a tibial support positioning base, which is provided with a limiting groove. The limiting groove includes a first limiting portion and a second limiting portion. The tibial support positioning base is adaptively connected to the lower end of the tibial shaft forming mold through the first limiting portion. The interior of the tibial shaft forming mold is connected to the second limiting portion, and the tibial support prosthesis is arranged in the second limiting portion.

6. The proximal tibial space-occupying prosthesis according to claim 4, characterized in that: The upper end of the tibial shaft forming mold is provided with a positioning portion, the positioning portion is connected to the medullary needle, and the lower end of the medullary needle is arranged in the forming space inside the tibial shaft forming mold.

7. A method for preparing a proximal tibial prosthesis according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: S1. Based on the patient's CT data, the tibial shaft molding mold and tibial tray positioning base are formed by 3D printing to make them consistent with the natural bone physiological structure; S2, placing the tibial tray positioning base on the support surface, and then placing the tibial tray prosthesis in the second limiting portion of the tibial tray positioning base; S3, sequentially arranging and splicing the multiple sub-molds constituting the tibial shaft forming mold, and inserting them into the first limiting portion of the tibial tray positioning base; S4, fixing the tibial tray positioning base to the tibial shaft forming mold through a connecting portion, and assembling the molds into a 3D printed tibial forming mold; S5, injecting the prepared bone cement into the tibial forming mold, inserting the medullary needle into the positioning portion of the tibial shaft forming mold before the bone cement solidifies, and then waiting for the bone cement to solidify and form; S6, removing the connecting portion of the tibial tray positioning base, and knocking off the tibial tray positioning base; S7. Knock down the sub-mold structures of the tibial shaft forming mold along the partition between the sub-molds, remove the completed mold, and obtain the proximal tibial prosthesis.

8. The method for preparing a proximal tibial prosthesis according to claim 7, characterized in that: The tibial tray prosthesis is made of cobalt-chromium-molybdenum material, the medullary pin is made of titanium alloy or cobalt-chromium-molybdenum material, and the size of the proximal tibial prosthesis is 5% to 10% smaller than the patient's natural bone.

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