Acetabular prosthesis

Abstract

The invention belongs to the technical field of medical instruments, and particularly discloses an acetabular prosthesis which comprises an acetabular cup mounted in an acetabular fossa. The acetabular cup and the filling block are connected in an embedded and clamped mode through the anti-rotation structure, and the acetabular cup and the filling block are fixed together through the first fixing nail. And the fixed wing is connected with the filling block and is fixed on the ilium wing. By means of the anti-rotation structure, when a patient implanted with the acetabular prosthesis moves and dislocation and slippage occur between the filling block and the acetabular cup, the first fixing nail cannot slightly move under the action of shearing force, the shearing force is borne by the anti-rotation structure, and the service life of the acetabular prosthesis is prolonged. According to the acetabular prosthesis, the first bone grafting groove and the supporting table are arranged on the filling block at intervals, the second bone grafting groove is formed in the acetabular cup, the weight of the acetabular prosthesis is reduced, autogenous bones or allogeneic bones of a patient can be implanted into the first bone grafting groove and the second bone grafting groove, the acetabular prosthesis is effectively prevented from loosening for a long time after being implanted, and the survival rate of the acetabular prosthesis is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to an acetabular prosthesis. Background Art

[0002] The incidence of DDH (congenital dysplasia of the hip) in my country is about 0.9‰ to 3‰. The acetabular side of patients with DDH type III or DDHIV is usually accompanied by anterior-superior or posterosuperior defects. In order to improve the patients' mobility function, the most effective way is to replace the bone defect with an artificial acetabular prosthesis to remove the lesion, eliminate pain and restore the patient's mobility function.

[0003] The artificial acetabular prosthesis mainly includes the acetabular cup and the filling block. The filling block can fill the bone defect in the cavity, making the patient's bone defect more complete, and effectively improving the fixation effect of the acetabular prosthesis. The acetabular prosthesis and the filling block are often fixed by fixing screws, but the connection method of fixing only by fixing screws has the following problems:

[0004] After the patient has the acetabular prosthesis implanted, dislocation and slippage will occur between the filling block and the acetabular cup during the patient's activities. As a result, the fixing pins will be subjected to shear force, causing micro-movement of the fixing pins and affecting the functional effect of the acetabular prosthesis. Summary of the invention

[0005] The purpose of the present invention is to provide an acetabular prosthesis. When a patient implanted with the acetabular prosthesis is moving and a filling block and an acetabular cup are dislocated or slipped, the fixing pins will not be subjected to shear force and micro-move, thereby increasing the service life of the acetabular prosthesis.

[0006] The object of the present invention is achieved through such a technical solution, an acetabular prosthesis, comprising:

[0007] Acetabular cup;

[0008] A filling block, the acetabular cup and the filling block are engaged and clamped by an anti-rotation structure, and the acetabular cup and the filling block are fixed together by a first fixing nail; and

[0009] Fixed wing, connected to the filling block.

[0010] Preferably, the anti-rotation structure is a cross-shaped anti-rotation structure, which is a cross-shaped anti-rotation groove and a cross-shaped anti-rotation ridge matched with the cross-shaped anti-rotation groove. The cross-shaped anti-rotation groove is arranged on the outer wall of the acetabular cup, and the cross-shaped anti-rotation ridge is arranged on the inner wall of the filling block.

[0011] Preferably, the outer wall of the acetabular cup is provided with a limiting groove matching the outer shape of the filling block, and the cross-shaped anti-rotation groove is arranged in the limiting groove.

[0012] Preferably, a first bone grafting groove and a support platform are spaced apart on the connection side of the filling block and the acetabular cup, and a second bone grafting groove matching the first bone grafting groove is provided in the limiting groove.

[0013] Preferably, the width of the support platform is 5-10 mm, and the width of the first bone grafting groove is 5-10 mm.

[0014] Preferably, the fixing wing extends toward and fits the iliac wing, and comprises a fixing wing body extending toward and fitting the iliac wing and fixing pins, wherein a plurality of fixing pins are arranged at intervals on the end surface of the fixing wing body facing the iliac wing.

[0015] Preferably, the fixing wing body is provided with a plurality of second through-threaded holes at intervals, the hole walls of the second through-threaded holes extend toward the filling block, and the second fixing nails obliquely pass through the second through-threaded holes to fix the fixing wing body on the iliac wing.

[0016] Preferably, the filling block and the fixing wing are integrally formed.

[0017] Preferably, the acetabular cup is provided with a first through-threaded hole, the filling block is provided with a third through-threaded hole connected with the first through-threaded hole, the first fixing nail obliquely passes through the first through-threaded hole and the third through-threaded hole, and the first fixing nail fixes the acetabular cup and the filling block.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] In the above-mentioned acetabular prosthesis, the acetabular cup and the filling block are engaged and clamped by an anti-rotation structure, and the acetabular cup and the filling block are fixed together by a first fixing pin. The anti-rotation structure can effectively prevent micro-movement between the acetabular cup and the filling block when the first fixing pin is tightened, and the shear force is borne by the anti-rotation structure. Therefore, when the patient with the implanted acetabular prosthesis is moving and there is dislocation and slippage between the filling block and the acetabular cup, the first fixing pin will not be affected by the shear force and micro-movement will occur, thereby increasing the service life of the acetabular prosthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation of the present invention, the following will briefly introduce the drawings required for use in the specific implementation. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0021] Figure 1 It is a schematic structural diagram of an acetabular prosthesis of the present invention;

[0022] Figure 2 It is a schematic diagram of the structure of the acetabular prosthesis combined with the human bone;

[0023] Figure 3 is a schematic diagram of the structure of the acetabular cup;

[0024] Figure 4A schematic diagram of the combination of the acetabular cup and the filler block;

[0025] Figure 5 It is a schematic diagram of the structure of the filling block and the fixed wing.

[0026] Reference numerals:

[0027] 1-acetabular cup, 11-cross-shaped anti-rotation groove, 12-limiting groove, 13-second bone grafting groove, 14-first through-threaded hole, 15-fourth through-threaded hole, 2-filling block, 21-cross-shaped anti-rotation ridge, 22-first bone grafting groove, 23-support platform, 24-third through-threaded hole, 3-fixing wing, 31-fixing wing body, 311-second through-threaded hole, 32-fixing pin, 4-first fixing nail, 5-second fixing nail, 6-third fixing nail, 7-iliac wing, 8-acetabular fossa. DETAILED DESCRIPTION

[0028] See also Figure 1 and Figure 2 An acetabular prosthesis includes an acetabular cup 1, a filling block 2 and a fixing wing 3. The acetabular cup 1 and the filling block 2 are connected by an anti-rotation structure interlocking card, and the acetabular cup 1 and the filling block 2 are fixed together by a first fixing nail 4. The fixing wing 3 is connected to the filling block 2.

[0029] Specifically, the acetabular cup 1, the filling block 2 and the fixed wing 3 are formed by 3D printing using the existing EBM (Electron Beam Melting) technology. The materials of the acetabular cup 1, the filling block 2 and the fixed wing 3 are preferably titanium alloy materials, and the elastic modulus of the titanium alloy is close to that of the human femur. After processing, the bone interface of the acetabular prosthesis is a porous structure of trabecular bone, and the porosity is 50% to 80%, thereby increasing the initial stability of the acetabular prosthesis, facilitating the long-term autologous bone growth, and realizing the long-term biological fixation of the acetabular prosthesis. The acetabular cup 1 is a hollow hemispherical shape, and is provided with a plurality of fourth through-threaded holes 15. The third fixing nail 6 passes through the fourth through-threaded hole 15 to fix the acetabular cup 1 in the patient's acetabular fossa 8. The acetabular cup 1 is rotatably connected to the femur, and the acetabular cup 1 bone interface contour can be customized according to the patient's CT data to ensure that the acetabular cup 1 is completely fitted with the acetabular defect. The shape of the filling block 2 and the fixed wing 3 is completely fitted with the acetabular defect and the iliac wing 7, improving the fixation effect. The fixing wing 3 is fixed on the iliac wing 7 .

[0030] The acetabular prosthesis in the present invention is a 3D-printed acetabular prosthesis customized according to the individual characteristics of the human body, which matches the actual defects of the human body, so that the acetabular prosthesis fully fits the human bone and promotes the effect of autologous bone ingrowth. The acetabular cup 1 and the filling block 2 are connected by an anti-rotation structure. The anti-rotation structure effectively prevents micro-movement between the acetabular cup 1 and the filling block 2, plays a positioning and anti-rotation role, and can also support the shear force borne by the cross anti-rotation structure when the first fixing pin 4 is tightened, and the fixing pin is not subjected to the shear force, thereby improving the life of the acetabular prosthesis.

[0031] For further information, see Figure 3 , Figure 4 and Figure 5 The anti-rotation structure is a cross-shaped anti-rotation structure, including a cross-shaped anti-rotation groove 11 and a cross-shaped anti-rotation ridge 21 adapted to the cross-shaped anti-rotation groove 11. The cross-shaped anti-rotation groove 11 is arranged on the outer wall of the acetabular cup 1, and the cross-shaped anti-rotation ridge 21 is arranged on the inner wall of the filling block 2.

[0032] Specifically, because the acetabular cup 1 is hemispherical, the cross anti-rotation structure is an inclined surface. The cross anti-rotation groove 11 is an iso-depth groove, and the inner wall width of the cross anti-rotation groove 11 is equal to the outer wall width of the cross anti-rotation ridge 21, so that the filling block 2 is embedded in the acetabular cup 1. With this structure, the cross anti-rotation groove 11 is not only used for positioning when installing the filling block 2, ensuring that they are correctly aligned and stable; but also can concentrate stress on the edge of the cross anti-rotation groove 11, disperse stress, reduce the degree of stress concentration, thereby improving tensile strength and fatigue resistance; and increase the contact area between the acetabular cup 1 and the filling block 2, thereby improving the friction and anti-slip performance of the acetabular cup 1 and the filling block 2, and increasing stability. With this structure, the first fixing nail 4 fixes the acetabular cup 1 and the filling block 2. When the patient is in an activity, the cross anti-rotation structure plays a role in positioning and anti-rotation when the first fixing nail 4 is tightened. When the first fixing pin 4 is tightened, the shear force is borne by the cross-shaped anti-rotation structure, and the first fixing pin 4 does not bear the shear force, which effectively prevents the first fixing pin 4 from loosening due to the shear force after implantation, thereby improving the life of the acetabular prosthesis. Preferably, the number and size of the cross-shaped anti-rotation structure can be determined by the size of the acetabular cup 1 and the filling block 2. It should be noted that the cross-shaped anti-rotation groove 11 can be provided on the inner wall of the filling block 2, and correspondingly, the cross-shaped anti-rotation ridge 21 is provided in the outer wall of the acetabular cup 1.

[0033] For further information, see Figure 3The outer wall of the acetabular cup 1 is provided with a limiting groove 12 that matches the shape of the filling block 2, and the cross-shaped anti-rotation groove 11 is arranged in the limiting groove 12. The limiting groove 12 not only serves as a limiting mark during installation, facilitating the positioning of the filling block 2 and quick installation, but also after the filling block 2 is installed, the limiting groove 12 limits the movement and rotation of the filling block 2, and there will be no dislocation or slippage between the filling block 2 and the acetabular cup 1, thereby reducing the shear force on the cross-shaped anti-rotation structure.

[0034] For further information, see Figure 3 and Figure 5 A first bone grafting groove 22 and a support platform 23 are arranged at intervals on the connection side of the filling block 2 and the acetabular cup 1, and a second bone grafting groove 13 that matches the first bone grafting groove 22 is provided in the limiting groove 12. On the one hand, the first bone grafting groove 22 can reduce the weight of the filling block 2, and the second bone grafting groove 13 can reduce the weight of the acetabular cup 1; on the other hand, the first bone grafting groove 22 can be implanted with the patient's autologous bone or allogeneic bone, and then the patient's autologous bone or allogeneic bone is extended to the second bone grafting groove 13. After the bone grafting block is recombined with the filling block 2 and the bone surface of the pelvic acetabular defect, the filling block 2 and the human pelvis can form a three-dimensional fixed form, which can effectively prevent the occurrence of long-term loosening of the acetabular prosthesis after implantation and improve the survival rate of the acetabular prosthesis. The bone interface contour of the filling block 2 can be customized according to the patient's CT data to ensure that the filling block 2 is fully fitted with the acetabular defect and the iliac wing 7 to improve the fixation effect.

[0035] For further information, see Figure 5 , the width of the support platform 23 is 5-10mm, and the width of the first bone grafting groove 22 is 5-10mm. The support platform 23 can effectively prevent the bone collapse under the acetabular prosthesis. The number of support platforms 23 can be determined by the size of the filling block 2. The width of the first bone grafting groove 22 is between 5-10mm, which can ensure sufficient autologous bone implantation and bone ingrowth after implantation, thereby ensuring the long-term fixation effect of the acetabular prosthesis. The number of the first bone grafting grooves 22 can be determined by the size of the filling block 2, and the second bone grafting groove 13 corresponds to the first bone grafting groove 22.

[0036] For further information, see Figure 5The fixing wing 3 extends toward the iliac wing 7 and fits the iliac wing 7, including a fixing wing body 31 and a fixing pin 32 extending toward the iliac wing 7 and fitting thereto, and a plurality of fixing pins 32 are arranged at intervals on the end surface of the fixing wing body 31 facing the iliac wing 7. Specifically, the front end of the fixing pin 32 has a sharp portion, which is easy to penetrate into the iliac wing 7. The size and shape of the fixing wing body 31 can be designed according to the patient's CT scan to fill the defect to the greatest extent and fit the iliac wing 7, thereby preventing the entire acetabular prosthesis from being flipped and dislocated due to the upward force, and then causing the acetabular prosthesis to fail. Preferably, two fixing pins 32 are provided. When in use, a positioning hole matching the fixing pin 32 is provided in the iliac wing 7, and the fixing pin 32 is inserted into the positioning hole to achieve initial stability, and then further fixed by the second fixing nail 5.

[0037] For further information, see Figure 1 and Figure 4 The fixing wing body 31 is provided with a plurality of second through-threaded holes 311 at intervals, and the hole wall of the second through-threaded hole 311 extends toward the filling block 2. The second fixing nail 5 obliquely passes through the second through-threaded hole 311 to fix the fixing wing body 31 on the iliac wing 7. The hole wall of the second through-threaded hole 311 obliquely extends toward the filling block 2, increasing the area of ​​the inner wall of the second through-threaded hole 311, increasing the contact area of ​​the second fixing nail 5 with the hole, and thus increasing the fixing strength.

[0038] For further information, see Figure 5 The filling block 2 and the fixing wing 3 are integrally formed to enhance the strength of the acetabulum.

[0039] For further information, see Figure 4 The acetabular cup 1 is provided with a first through-threaded hole 14, the filling block 2 is provided with a third through-threaded hole 24 connected with the first through-threaded hole 14, the first fixing nail 4 obliquely passes through the first through-threaded hole 14 and the third through-threaded hole 24, and the first fixing nail 4 fixes the acetabular cup 1 and the filling block 2. Specifically, the first through-threaded hole 14 and the third through-threaded hole 24 are arranged along the radial direction of the acetabular cup 1, which increases the area of ​​the inner wall of the first through-threaded hole 14 and the third through-threaded hole 24, increases the contact area of ​​the first fixing nail 4 with them, and thus increases the fixing strength.

[0040] In the above-mentioned acetabular prosthesis, the acetabular cup 1, the filling block 2 and the fixing wing 3 can be designed in size and shape according to the patient's CT, so as to maximize the effect of filling defects and fitting the bone surface, thereby improving the initial stability of the acetabular prosthesis system. The acetabular cup 1 and the filling block 2 are assembled through the limiting groove 12 and the cross-shaped anti-rotation structure is interlocked and clamped, so that they can be quickly installed to prevent displacement and rotation between the acetabular cup 1 and the filling block 2. The first fixing nail 4 fixes the acetabular cup 1 and the filling block 2 together, and the anti-rotation structure can effectively prevent micro-movement between the acetabular cup 1 and the filling block 2 when the first fixing nail 4 is tightened. The shear force is borne by the anti-rotation structure, so that when the patient with the acetabular prosthesis implanted is in motion, when the filling block 2 and the acetabular cup 1 are dislocated and slipped, the fixing nail will not be subjected to the shear force and micro-movement occurs, thereby improving the long-term stability of the acetabular prosthesis and increasing the service life of the acetabular prosthesis.

[0041] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the scope of the present invention should be included in the protection scope of the present invention.

Claims

1. An acetabular prosthesis, It is characterized in that include: Acetabular cup (1); The acetabular cup (1) and the filling block (2) are engaged and clamped together through an anti-rotation structure, and the first fixing pin (4) fixes the acetabular cup (1) and the filling block (2) together; and The fixed wing (3) is connected to the filling block (2).

2. The acetabular prosthesis according to claim 1, It is characterized in that The anti-rotation structure is a cross-shaped anti-rotation structure, which comprises a cross-shaped anti-rotation groove (11) and a cross-shaped anti-rotation ridge (21) adapted to the cross-shaped anti-rotation groove (11); the cross-shaped anti-rotation groove (11) is arranged on the outer wall of the acetabular cup (1), and the cross-shaped anti-rotation ridge (21) is arranged on the inner wall of the filling block (2).

3. The acetabular prosthesis according to claim 1 or 2, It is characterized in that The outer wall of the acetabulum cup (1) is provided with a limiting groove (12) matching the outer shape of the filling block (2), and the cross-shaped anti-rotation groove (11) is arranged in the limiting groove (12).

4. The acetabular prosthesis according to claim 3, It is characterized in that A first bone grafting groove (22) and a support platform (23) are arranged at intervals on the connection side between the filling block (2) and the acetabular cup (1), and a second bone grafting groove (13) matching with the first bone grafting groove (22) is arranged in the limiting groove (12).

5. The acetabular prosthesis according to claim 4, It is characterized in that The width of the support platform (23) is 5-10 mm, and the width of the first bone grafting groove (22) is 5-10 mm.

6. Acetabular prosthesis according to claim 1, 2, 4 or 5, It is characterized in that The fixing wing (3) extends toward the iliac wing (7) and fits the iliac wing (7), and comprises a fixing wing body (31) extending toward and fitting the iliac wing (7) and fixing pins (32), wherein a plurality of fixing pins (32) are arranged at intervals on the end surface of the fixing wing body (31) facing the iliac wing (7).

7. The acetabular prosthesis according to claim 6, It is characterized in that The fixing wing body (31) is provided with a plurality of second through-threaded holes (311) at intervals, the hole walls of the second through-threaded holes (311) extend toward the filling block (2), and the second fixing nails (5) obliquely pass through the second through-threaded holes (311) to fix the fixing wing body (31) on the iliac wing (7).

8. The acetabular prosthesis according to claim 1, 2, 4, 5 or 7, It is characterized in that The filling block (2) and the fixed wing (3) are integrally formed.

9. The acetabular prosthesis according to claim 1, 2, 4, 5 or 7, It is characterized in that The acetabular cup (1) is provided with a first through-threaded hole (14), the filling block (2) is provided with a third through-threaded hole (24) connected to the first through-threaded hole (14), the first fixing nail (4) obliquely passes through the first through-threaded hole (14) and the third through-threaded hole (24), and the first fixing nail (4) fixes the acetabular cup (1) and the filling block (2).

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