A new 3D printing self-stabilizing total sacrum assembly prosthesis
The self-stabilizing full sacral prosthesis manufactured by 3D printing, with its detachable concave-convex mating structure and porous trabecular bionic interface, solves the problems of long-term stability and nerve traction risk of full sacral prostheses, and achieves stable connection of the prosthesis and skeletal fusion.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WEST CHINA HOSPITAL SICHUAN UNIV
- Filing Date
- 2026-03-09
- Publication Date
- 2026-06-09
AI Technical Summary
Existing total sacral prostheses are prone to anterior or posterior displacement under long-term mechanical stress, and there is a high risk of nerve traction during sacral tumor resection and prosthesis reconstruction, making it difficult to achieve reliable stability and safety.
A self-stabilizing, modular sacral prosthesis is manufactured using 3D printing technology. Through a detachable, convex-concave mating structure and multiple self-stabilizing designs, including mortise and tenon structures and porous trabecular bionic interfaces, a stable connection between the prosthesis and the iliac bone is achieved, avoiding nerve traction.
It improves the short-term and long-term stability of the prosthesis in the reconstruction area, reduces the risk of intraoperative nerve traction injury, and enhances the fusion effect between the prosthesis and the bone.
Smart Images
Figure CN122163358A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical prosthesis technology, specifically to a novel 3D-printed self-stabilizing full sacral modular prosthesis. Background Technology
[0002] The sacrum is located in the lower segment of the spine, forming the lumbosacral joint with the lumbar vertebrae above and the sacroiliac joint with the iliac bones of the pelvis on both sides below. This region not only transmits forces from the spine to the pelvis but also provides important support for the lower limbs. Furthermore, the sacrum contains numerous sacrococcygeal neural structures responsible for sensory and motor functions in the buttocks and surrounding areas. For malignant tumors of the sacrum, surgical resection remains the primary treatment. After total or partial sacral resection, a lumbosacral screw system (spinal rod system) is often used to connect the spine to the pelvis. This system typically uses pedicle screws and rods to fix the spine, sacrum, and iliac bones together, allowing the forces on the spine to be directly transmitted to the iliac bones. However, this method often sacrifices some normal lumbar spine mobility, and in the case of total sacral resection, the lack of sacral support can lead to insufficient stability of the prosthesis or fixation system under its own weight and the lumbar lordosis moment. Current total sacral prostheses are generally fixed to the L5 vertebral body and iliac bones with screws, but under long-term mechanical stress, they may still shift anteriorly or inferiorly, making reliable stability difficult to achieve. Meanwhile, during sacral tumor resection and prosthesis reconstruction, the limited operating space and high risk of nerve traction may affect postoperative limb function recovery.
[0003] With the development of 3D printing technology, its personalized manufacturing capabilities have led to its increasing application in the field of customized medical prostheses. Therefore, it is necessary to develop a full sacral prosthesis with self-stabilizing characteristics and easy modular assembly to improve the short-term and long-term stability of the prosthesis in the reconstruction area and reduce the risk of intraoperative nerve traction injury. Summary of the Invention
[0004] To address the shortcomings of the existing technology, this invention provides a novel 3D-printed self-stabilizing full sacral modular prosthesis, which improves the short-term and long-term stability of the prosthesis in the reconstruction area and reduces the risk of intraoperative nerve traction injury.
[0005] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows: A novel 3D-printed self-stabilizing full sacral prosthesis includes a prosthesis body comprising a left iliac bone connecting block and a right iliac bone connecting block. The left and right iliac bone connecting blocks are 3D printed and assembled using a detachable concave-convex fitting structure and fixed with screws. The assembled middle section forms a vertebral body connecting part for connection with the L5 vertebral body. The top of the vertebral body connecting part has a vertebral body connecting surface that abuts against the L5 vertebral body, and a baffle is provided at the front of the vertebral body connecting surface, abutting against the anterior side of the L5 vertebral body. The outer end of the left iliac bone connecting block has a left iliac bone connecting surface that abuts against the left iliac bone osteotomy surface, and the outer end of the right iliac bone connecting block has a right iliac bone connecting surface that abuts against the right iliac bone osteotomy surface. With the human body in a standing position, head is considered top, feet bottom, front front, and back back, and the left and right iliac bone connecting surfaces form a double "eight" shape, narrower at the front and wider at the back, and narrower at the bottom and wider at the top.
[0006] Furthermore, the left iliac bone connecting block has a rear overlapping block on the right side and a front overlapping block on the left side, and the left iliac bone connecting block and the right iliac bone connecting block overlap and cooperate; the concave-convex cooperation structure is a tenon and mortise structure provided on the overlapping surface of the rear overlapping block and the front overlapping block.
[0007] Furthermore, the rear overlapping block is provided with a tenon structure, and the front overlapping block is provided with a mortise structure, or the rear overlapping block is provided with a mortise structure and the front overlapping block is provided with a tenon structure, wherein the tenon structure and the mortise structure are adapted to each other.
[0008] Furthermore, the upper end of the left iliac bone connecting surface is provided with a left iliac bone flap that abuts against the upper edge of the left iliac bone, and the upper end of the right iliac bone connecting surface is provided with a right iliac bone flap that abuts against the upper edge of the right iliac bone, which is used to restrict the downward movement of the prosthesis.
[0009] Furthermore, the lower end of the left iliac bone connecting surface is provided with a left iliac bone plate that abuts against the dorsal side of the left iliac bone; the lower end of the right iliac bone connecting surface is provided with a right iliac bone plate that abuts against the dorsal side of the right iliac bone, which is used to limit the anterior displacement of the prosthesis.
[0010] Furthermore, the posterior overlapping block of the left iliac bone connecting block and the anterior overlapping block of the right iliac bone connecting block are provided with a first countersunk screw hole that runs from bottom to top, for the bone nail to pass through and connect to the fifth lumbar vertebra.
[0011] Furthermore, the left iliac bone connecting block is provided with a second countersunk screw hole penetrating the connecting surface of the left iliac bone, and the right iliac bone connecting block is provided with a second countersunk screw hole penetrating the connecting surface of the right iliac bone, respectively for the bone screw to pass through and connect the left iliac bone and the right iliac bone.
[0012] Furthermore, the left iliac bone plate and the right iliac bone plate are respectively provided with a through third countersunk screw hole for the bone screw to pass through and connect the left iliac bone and the right iliac bone.
[0013] Furthermore, the vertebral body connection surface, the left iliac bone connection surface, and the right iliac bone connection surface are all provided with porous trabecular bionic interfaces.
[0014] The beneficial effects of this invention are: The novel 3D-printed self-stabilizing modular prosthesis of the entire sacrum is suitable for the reconstruction of the lumbosacral joint with bone defects after total sacral tumor resection. It is made by 3D printing, which enables personalized customization and adaptation with a high degree of matching. The modular design allows for segmented installation during surgery, making implantation convenient and minimizing nerve traction damage during the prosthesis installation process, thus improving the patient's postoperative limb function.
[0015] This invention relates to a novel 3D-printed self-stabilizing full sacral prosthesis. The prosthesis itself features multiple self-stabilizing structures that prevent anterior and posterior displacement, resulting in excellent stability and preventing postoperative lumbar lordosis. It conforms to the biomechanical transmission of the sacroiliac joint, and the porous trabecular interface promotes osseointegration, leading to excellent long-term stability. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 yes Figure 1 Rear view; Figure 3 yes Figure 1 Top view; Figure 4 yes Figure 1 A bottom view; Figure 5 This is the front view in the application state; Figure 6 This is a top view in the application state; Figure 7 This is a schematic diagram of the split structure according to an embodiment of the present invention.
[0018] Reference numerals: 1-vertebral body connection, 2-left iliac bone connection block, 3-right iliac bone connection block, 4-L5 vertebral body, 5-left iliac bone, 6-right iliac bone, 11-vertebral body connection surface, 12-baffle, 13-first countersunk screw hole, 21-left iliac bone connection surface, 22-left iliac bone wing, 23-left iliac bone plate, 24-tenon structure; 31-right iliac bone connection surface, 32-right iliac bone wing, 33-right iliac bone plate, 34-mortise structure. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0020] A novel 3D-printed self-stabilizing modular sacral prosthesis includes a prosthesis body, such as... Figures 1-7 As shown, the prosthesis body includes a left iliac bone connecting block 2 and a right iliac bone connecting block 3. The left iliac bone connecting block 2 and the right iliac bone connecting block 3 are respectively 3D printed and assembled and connected by a detachable concave-convex fitting structure and fixed by screws. The middle part after assembly forms a vertebral body connecting part 1 for connecting with the L5 vertebral body 4. The top of the vertebral body connecting part 1 is provided with a vertebral body connecting surface 11 that abuts against the bottom surface of the L5 vertebral body 4, and a baffle 12 is provided at the front of the vertebral body connecting surface 11. The baffle 12 abuts against the front side of the fifth lumbar vertebra 4; the outer end of the left iliac bone connecting block 2 is provided with a left iliac bone connecting surface 21 that abuts against the osteotomy surface of the left iliac bone 5, and the outer end of the right iliac bone connecting block 3 is provided with a right iliac bone connecting surface 31 that abuts against the osteotomy surface of the right iliac bone 6. With the human body standing position defined as head above, feet below, front front, and back back, the left iliac bone connecting surface 21 and the right iliac bone connecting surface 31 are in a double "eight" shape that is "narrow in front and wide in back, narrow at the bottom and wide at the top".
[0021] In the vertical direction, the body weight can press and fix the prosthesis body to the iliac bone osteotomy surface, while the "narrow at the bottom and wide at the top" shape restricts the downward movement of the prosthesis body. In the anterior-posterior direction, the physiological lordosis of the L5 vertebral body 4 fixes the prosthesis body to the iliac bone osteotomy surface, while the "narrow at the front and wide at the back" shape restricts the forward movement of the prosthesis body. The baffle 12 abuts against the anterior side of the L5 vertebral body 4, which can also restrict the forward movement of the L5 vertebral body 4. Thus, the prosthesis body can achieve self-limitation in the anterior-posterior and vertical directions, increasing the stability of the prosthesis body.
[0022] Preferably, the left iliac bone connecting block 2 has a rear overlapping block on its right side, and the right iliac bone connecting block 3 has a front overlapping block on its left side, with the left iliac bone connecting block 2 and the right iliac bone connecting block 3 overlapping and fitting together; the convex-concave fitting structure is a tenon and mortise structure provided on the overlapping surfaces of the rear and front overlapping blocks. Preferably, the rear overlapping block has a tenon structure 24, and the front overlapping block has a mortise structure 34, or the rear overlapping block has a mortise and mortise structure, and the front overlapping block has a tenon structure, with the tenon structure 24 and the mortise structure 34 fitting together.
[0023] Furthermore, the upper end of the left iliac bone connecting surface 21 is provided with a left iliac bone wing 22 that abuts against the upper edge of the left iliac bone 5, and the upper end of the right iliac bone connecting surface 31 is provided with a right iliac bone wing 32 that abuts against the upper edge of the right iliac bone 6. The left iliac bone wing 22 and the right iliac bone wing 32 abut against the upper edges of the bilateral iliac bones respectively, thus restricting the downward movement of the prosthesis.
[0024] Furthermore, the lower end of the left iliac bone connecting surface 21 is provided with a left iliac bone plate 23 that abuts against the dorsal side of the left iliac bone 5; the lower end of the right iliac bone connecting surface 31 is provided with a right iliac bone plate 33 that abuts against the dorsal side of the right iliac bone 6; the left iliac bone plate 23 and the right iliac bone plate 33 abut against the dorsal sides of both iliac bones respectively, restricting the anterior movement of the prosthesis.
[0025] Furthermore, the posterior overlapping block of the left iliac bone connecting block 2 and the anterior overlapping block of the right iliac bone connecting block 3 are provided with a first countersunk screw hole 13 extending from bottom to top, for the bone screw to pass through and connect to the patient's fifth lumbar vertebra 4; the left iliac bone connecting block 2 is provided with a second countersunk screw hole extending through the left iliac bone connecting surface 21, and the right iliac bone connecting block 3 is provided with a second countersunk screw hole extending through the right iliac bone connecting surface 31, for the bone screw to pass through and connect to the patient's left iliac bone 5 and right iliac bone 6, respectively. The left iliac bone plate 23 and the right iliac bone plate 33 are respectively provided with a third countersunk screw hole extending through, for the bone screw to pass through and connect to the left iliac bone 5 and right iliac bone 6.
[0026] Preferably, the vertebral body connecting surface 11, the left iliac bone connecting surface 21, and the right iliac bone connecting surface 31 are all provided with porous trabecular bionic interfaces to promote the fusion of the prosthesis with the body bone.
[0027] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.
Claims
1. A novel 3D-printed self-stabilizing full sacral modular prosthesis, comprising a prosthesis body, characterized in that: The prosthesis body includes a left iliac bone connecting block (2) and a right iliac bone connecting block (3); the left iliac bone connecting block (2) and the right iliac bone connecting block (3) are respectively 3D printed and assembled and connected by a detachable concave-convex fitting structure and fixed by screws. The middle part after assembly forms a vertebral body connecting part (1) for connecting with the fifth lumbar vertebra (4); the top of the vertebral body connecting part (1) is provided with a vertebral body connecting surface (11) that abuts against the bottom surface of the fifth lumbar vertebra (4), and a baffle (12) is provided at the front of the vertebral body connecting surface (11). The baffle (12) abuts against the front side of the fifth lumbar vertebra (4); the outer end of the left iliac bone connecting block (2) is provided with a left iliac bone connecting surface (21) that abuts against the osteotomy surface of the left iliac bone (5), and the outer end of the right iliac bone connecting block (3) is provided with a right iliac bone connecting surface (31) that abuts against the osteotomy surface of the right iliac bone (6). With the human body standing position defined as head above, feet below, front front, and back back, the left iliac bone connecting surface (21) and the right iliac bone connecting surface (31) are in the shape of a double "eight" with "narrow in front and wide in back, narrow at the bottom and wide at the top".
2. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 1, characterized in that: The left iliac bone connecting block (2) has a rear overlapping block on the right side and the right iliac bone connecting block (3) has a front overlapping block on the left side. The left iliac bone connecting block (2) and the right iliac bone connecting block (3) overlap and cooperate. The concave-convex cooperation structure is a tenon and mortise structure set on the overlapping surface of the rear overlapping block and the front overlapping block.
3. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 2, characterized in that: The rear overlapping block is provided with a tenon structure (24), the front overlapping block is provided with a mortise structure (34), or the rear overlapping block is provided with a mortise structure and the front overlapping block is provided with a tenon structure, the tenon structure (24) and the mortise structure (34) are adapted to each other.
4. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 1, characterized in that: The upper end of the left iliac bone connecting surface (21) is provided with a left iliac bone flap (22) that abuts against the upper edge of the left iliac bone (5), and the upper end of the right iliac bone connecting surface (31) is provided with a right iliac bone flap (32) that abuts against the upper edge of the right iliac bone (6), which is used to restrict the downward movement of the prosthesis.
5. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 1 or 4, characterized in that: The lower end of the left iliac bone connecting surface (21) is provided with a left iliac bone plate (23) that abuts against the dorsal side of the left iliac bone (5); the lower end of the right iliac bone connecting surface (31) is provided with a right iliac bone plate (33) that abuts against the dorsal side of the right iliac bone (6), which is used to restrict the anterior movement of the prosthesis.
6. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 2, characterized in that: The posterior overlapping block of the left iliac bone connecting block and the anterior overlapping block of the right iliac bone connecting block are provided with a first countersunk screw hole that runs from bottom to top, for the bone nail to pass through and connect to the fifth lumbar vertebra.
7. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 1, characterized in that: The left iliac bone connecting block (2) is provided with a second countersunk screw hole that penetrates the left iliac bone connecting surface (21), and the right iliac bone connecting block (3) is provided with a second countersunk screw hole that penetrates the right iliac bone connecting surface (31), respectively for bone nails to pass through and connect the left iliac bone (5) and the right iliac bone (6).
8. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 5, characterized in that: The left iliac bone plate (23) and the right iliac bone plate (33) are respectively provided with a through third countersunk screw hole for the bone nail to pass through and connect the left iliac bone (5) and the right iliac bone (6).
9. The novel 3D-printed self-stabilizing full sacral modular prosthesis according to claim 1, characterized in that: The vertebral body connection surface (11), the left iliac bone connection surface (21), and the right iliac bone connection surface (31) are all provided with porous trabecular bionic interfaces.