Assembled sacrum reconstruction prosthesis

Abstract

The utility model belongs to the field of artificial prostheses, and particularly relates to an assembled sacrum reconstruction prosthesis. The device comprises two centrum installation blocks which are symmetrically distributed and attached to each other, a positioning block is arranged between the two centrum installation blocks, installation grooves are formed in the two centrum installation blocks, fusion layers are arranged on the attached faces of the two centrum installation blocks, and wave-shaped grooves matched with each other are formed in the two fusion layers; connecting blocks which are symmetrically distributed and attached to each other are fixed to the bottoms of the two cone installation blocks, the two connecting blocks are fixed through screws, and connecting assemblies are installed on the two connecting blocks. The sacrum tumor resection device is suitable for various sacrum tumor resection conditions and meets the requirements of reconstruction of different patients. During total sacrum reconstruction, when the wave-shaped grooves in the two fusion layers are attached to each other and matched with each other, the two centrum mounting blocks can be positioned; when the semi-sacrum is reconstructed, the wavy grooves can promote adhesion, proliferation and differentiation of bone cells, and the stability of the centrum mounting block is further enhanced.

Description

Technical Field

[0001] The utility model belongs to the field of artificial prostheses, in particular to a modular sacrum reconstruction prosthesis. Background Art

[0002] The sacrum is an important part of the pelvis and spine, and the pelvis is the bony component between the trunk spine and the free lower limb bones, playing an important role in conducting gravity and protecting the pelvic organs. The most common sacral lesion is sacral tumor disease, which can be divided into simple tumor resection, hemi-sacral tumor resection and total sacral tumor resection according to the condition of the sacral tumor. Sacral reconstruction is necessary after sacral defect. Sacral reconstruction is a complex and difficult process. With the development of science and technology, sacral prostheses can be accurately printed through 3D printing technology to ensure perfect fit. However, 3D printed prostheses have certain defects. First, they are all customized and have a long manufacturing cycle; second, 3D printed prostheses are designed through preoperative films. If there is an error in the sacrum removed during surgery, the 3D printed prosthesis will no longer be applicable.

[0003] For example, the Chinese utility model patent with application number CN202121238873.8 discloses a modular sacral reconstruction prosthesis, including a vertebral receiving portion for receiving a lumbar vertebral body and an iliac connection component connected to the vertebral receiving portion, the vertebral receiving portion is provided with a first screw hole for connecting to the lumbar vertebral body, and the iliac connection component has two groups, the two groups of iliac connection components are symmetrically arranged on both sides of the vertebral receiving portion, and the two groups of iliac connection components are respectively used to connect to the left ilium and the right ilium. In the above, the angle combination between the fixing part and the iliac connection plate, the fixing part and the vertebral receiving part is changed, and the iliac connection plate can be adjusted within 360 degrees in both directions, which is suitable for different patients with different bone interface orientations, meeting the needs of accurate reconstruction of the bone interface of different patients, and the vertebral receiving part, the iliac connection plate, and the fixing part can be assembled, and the above components of different sizes and models are pre-manufactured. Each case can select components of different sizes and models according to the corresponding data measured in real time during the operation, so as to realize the free assembly of the sacral prosthesis during the operation, without customization, and can be used at any time.

[0004] However, in sacral tumor resection, surgical treatment methods include hemi-sacral tumor resection and total sacral tumor resection, depending on the sacral tumor conditions of different patients. The above-mentioned prosthesis is only suitable for use in the case of total sacral tumor resection, and the applicable scenarios are relatively single, which makes it difficult to meet the requirements of precise reconstruction of different patients. Utility Model Content

[0005] In view of the above deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a modular sacral reconstruction prosthesis suitable for various sacral tumor resection situations and to meet the requirements of precise reconstruction for different patients.

[0006] The modular sacrum reconstruction prosthesis comprises two vertebral mounting blocks which are symmetrically distributed and fit together, a positioning block is arranged between the two vertebral mounting blocks, mounting grooves for independently engaging the positioning blocks are provided on the two vertebral mounting blocks, fusion layers are provided on the fitting surfaces of the two vertebral mounting blocks, and the two fusion layers are provided with wavy grooves which cooperate with each other; symmetrically distributed and mutually fitting connecting blocks are fixed to the bottom of the two vertebral mounting blocks, the two connecting blocks are fixed by screws, and iliac connecting components which are respectively used to connect the left and right iliac bones are detachably installed on the two connecting blocks.

[0007] Furthermore, the iliac connection component includes two iliac connection plates, on which the two connection blocks are respectively detachably mounted with freely rotatable and mutually symmetrical connecting rods, on which the front side walls of the unconnected ends of the two connecting rods are respectively detachably mounted with freely rotatable rotating blocks, all the connection blocks and all the rotating blocks are respectively provided with locking components for locking the rotating blocks and the connecting rods after rotation, and the two iliac connection plates are symmetrically distributed and respectively fixed on the two rotating blocks.

[0008] Furthermore, a metal sintered porous coating for improving bone ingrowth effect is formed on the top of each vertebral mounting block and on the surface of each iliac connecting plate that contacts the ilium.

[0009] Furthermore, the porosity of the metal sintered porous coating is 30-50%, and the pore diameter of the metal sintered porous coating is 100-600 μm.

[0010] Furthermore, the thickness of the iliac connection plate is 5-15 mm.

[0011] Furthermore, the locking assembly includes four fixing rings, each of which is provided with a plurality of positioning rods at equal intervals in the circumferential direction, all rotating blocks and connecting blocks are provided with a plurality of through holes for the positioning rods to pass through, and corresponding to all the through holes, a plurality of mounting holes for inserting the positioning rods are provided on the two connecting rods.

[0012] Furthermore, a first size scale is provided on all connecting blocks, a first alignment line for aligning with the scale line on the first size scale is provided on the front side walls of the two connecting rods, a second size scale is provided on all rotating blocks, and a second alignment line for aligning with the scale line on the second size scale is provided on the front side walls of the two connecting rods.

[0013] Furthermore, the positioning rod is made of titanium alloy.

[0014] Furthermore, the fusion layer is a metal sintered porous coating.

[0015] Furthermore, the porosity of the metal sintered porous coating is 30-50%, and the pore diameter of the metal sintered porous coating is 100-600 μm.

[0016] Furthermore, the positioning block is made of titanium alloy.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] The two vertebral mounting blocks are combined through the positioning cooperation between the positioning block and the two fusion layers with wave-shaped grooves. The two combined vertebral mounting blocks are fixed to the lumbar vertebrae in the state of total sacrum resection to reconstruct the sacral function; of course, they can also be fixed to the lumbar vertebrae through one vertebral mounting block, and can be fixed to the lumbar vertebrae in the state of half sacrum resection to reconstruct the function of half of the sacrum; thus, it is suitable for various sacral tumor resection situations and meets the requirements of precise reconstruction of different patients.

[0019] When the wavy grooves on the two fusion layers are reconstructed after total sacrum resection, the wavy grooves on the two fusion layers can effectively position the two vertebral mounting blocks when they fit together and cooperate with each other, so that the two vertebral mounting blocks are not easily misplaced up and down; during semi-sacrum reconstruction, the wavy grooves can increase the roughness of the prosthesis surface, thereby promoting the adhesion, proliferation and differentiation of bone cells. The grooves can also provide space for bone tissue growth, guide bone tissue to grow into the fusion layer, and further enhance the stability of the vertebral mounting blocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the utility model;

[0021] Figure 2 It is a front view of the utility model;

[0022] Figure 3 It is a three-dimensional schematic diagram of the utility model;

[0023] Figure 4 It is a three-dimensional explosion schematic diagram of the utility model;

[0024] Figure 5 This is a schematic diagram of the use of the utility model during total sacral tumor resection;

[0025] Figure 6 This is a schematic diagram of the use of the utility model in the resection of a hemisacral tumor;

[0026] The names of the components in the figure are: 1. iliac connecting plate 2, positioning rod 3, connecting rod 4, connecting block 5, vertebral mounting block 6, positioning block 7, fixing ring 8, first size scale 9, second size scale 10, rotating block 11, fusion layer. DETAILED DESCRIPTION

[0027] The present invention is further described below through specific embodiments in conjunction with the accompanying drawings, but the present invention is not limited thereto. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0028] Example 1

[0029] The modular sacral reconstruction prosthesis described in this embodiment is as follows: Figure 1 , Figure 4 and Figure 6 As shown, it includes two symmetrically distributed and mutually fitted vertebral mounting blocks 5, the two vertebral mounting blocks 5 are used to imitate the sacrum and are both made of titanium alloy. Of course, stainless steel, titanium and cobalt-based alloys can also be used; two first screw holes are opened on the two vertebral mounting blocks 5, which are connected up and down, and the lumbar vertebral body and the top of the two vertebral mounting blocks 5 are connected by bone screws. The bone screws pass through the first screw holes from bottom to top and are screwed into the lumbar vertebral body, so that the two vertebral mounting blocks 5 and the lumbar vertebral body form a "lumbar sacral part", which plays a role in restoring the "vertebral anterior column";

[0030] A positioning block 6 is arranged between the two vertebral mounting blocks 5. The two vertebral mounting blocks 5 are provided with mounting grooves for independently engaging the positioning block 6. In this embodiment, the positioning block 6 is made of titanium alloy, and of course, stainless steel, titanium and cobalt-based alloys can also be used; the positioning block 6 is a rectangular structure, and of course, a cylindrical, spherical or elliptical shape can also be used. When full sacrum reconstruction is required, the positioning block 6 is engaged in the mounting grooves on the two vertebral mounting blocks 5 to position the two vertebral mounting blocks 5 so that the two vertebral mounting blocks 5 are aligned in a mirror image.

[0031] A fusion layer 11 is provided on the surfaces of the two vertebral mounting blocks 5 that are in contact with each other. The fusion layer 11 is a metal sintered porous coating. The porosity of the metal sintered porous coating is 30-50%, and the pore diameter of the metal sintered porous coating is 100-600 μm, so as to achieve rapid bone growth, form biological fusion, further enhance the stability of the sacroiliac joint after reconstruction, achieve medium- and long-term biological stability after reconstruction, maintain the body's morphology and stability, and enable the patient to restore normal physiological functions. In this embodiment, the vertebral mounting block 5 is preferably made of titanium metal material, and of course, stainless steel, titanium alloy or cobalt-based alloy, etc. can also be used;

[0032] The two fusion layers 11 are provided with wavy grooves that match each other. The wavy grooves on the two fusion layers 11 are transverse waves. When the wavy grooves on the two fusion layers 11 fit together and match each other, the two vertebral mounting blocks 5 can be effectively positioned, so that the two vertebral mounting blocks 5 are not easily misplaced up and down; during semi-sacral reconstruction, the wavy grooves can increase the roughness of the prosthesis surface, thereby promoting the adhesion, proliferation and differentiation of bone cells. The grooves can also provide space for bone tissue growth, guide bone tissue to grow into the fusion layer 11, and further enhance the stability of the vertebral mounting block 5. The grooves can also increase the contact area between the vertebral mounting block 5 and the bone tissue, improve the friction between the vertebral mounting block 5 and the bone tissue, and prevent the vertebral mounting block 5 from moving or loosening;

[0033] The bottom of the two vertebral mounting blocks 5 are fixed with symmetrically distributed and mutually fitting connecting blocks 4, and the fitting surface of the vertebral mounting block 5 is flush with the fitting surface of the connecting block 4 fixed thereon, so that when the two vertebral mounting blocks 5 are fitted to each other, the two connecting blocks 4 will also fit to each other at the same time;

[0034] The two connecting blocks 4 are fixed by screws (locking pieces), and the corresponding screws are provided with first through holes communicating with each other on the two connecting blocks 4, one of which is provided with a thread, and the two fitted connecting blocks 4 are locked by rotating the screws, thereby locking the two vertebral mounting blocks 5; of course, the locking pieces can also be bolts and nuts, and the corresponding bolts are provided with second through holes communicating with each other on the two connecting blocks 4, the threaded ends of the bolts pass through the two second through holes, the nuts are sleeved on the threaded ends of the bolts, and the two connecting blocks 4 are squeezed by the hexagonal ends of the bolts and the nuts, thereby locking the two fitted connecting blocks 4, thereby locking the two vertebral mounting blocks 5.

[0035] To further explain, Figure 1 , Figure 4 and Figure 5As shown, the present embodiment preferably includes two iliac connecting plates 1, and the two connecting blocks 4 are respectively and detachably mounted with connecting rods 3 that can rotate freely and are symmetrical to each other. In the present embodiment, the two connecting rods 3 are made of titanium alloy, and of course stainless steel, titanium and cobalt-based alloys can also be used; the two connecting rods 3 are respectively fixed to the two connecting blocks 4 by first screws, and the two connecting blocks 4 are provided with third through holes for the first screws to pass through, and corresponding to the third through holes, threaded mounting holes that are threadedly matched with the first screws are provided on the fixed ends of the two connecting rods 3, and the first screws are in a relaxed state. The connecting rod 3 can rotate, so that the two iliac connecting plates 1 can swing back and forth at an angle suitable for the purpose. It is used for different patients with different bone interface orientations to meet the needs of accurate reconstruction of bone interfaces of different patients. After the angle is adjusted, tighten the first screw to lock the adjusted connecting rod 3, thereby locking the iliac connecting plate 1 after the angle is adjusted; the front side walls of the unconnected ends of the two connecting rods 3 are respectively detachably installed with freely rotatable rotating blocks 10. In the embodiment of this city, the two rotating blocks 10 are made of titanium alloy, and of course stainless steel, titanium and cobalt-based alloys can also be used; the two rotating blocks 10 are respectively fixed to the two connecting rods 3 by the second screw, and the two rotating blocks 10 are provided with a fourth through hole for the second screw to pass through, and the corresponding fourth through hole is at the unconnected ends of the two connecting rods 3. A threaded fixing hole is provided on the fixed end to be threadedly matched with the second screw. When the second screw is in a loose state, the rotating block 10 can be rotated, so that the two iliac connecting plates 1 can swing up and down. After the angle is adjusted, the second screw is tightened to lock the adjusted rotating block 10, thereby locking the adjusted iliac connecting plate 1; when the angle adjustment of all iliac connecting plates 1 is completed, the two iliac connecting plates 1 are fitted with the osteotomy surfaces on the left and right iliac bones, and fixed with bone screws; the two iliac connecting plates 1 are symmetrically distributed and fixed on the two rotating blocks 10 respectively. In this embodiment, the two iliac connecting plates 1 are made of titanium alloy, and of course stainless steel, titanium and cobalt-based alloys, etc.; the thickness of the iliac connection plate 1 is 5-15mm, and the iliac connection plate 1 is set to a variety of sizes with a difference of 5mm in thickness, and is pre-manufactured for standby use. It is selected according to actual needs, and preferably has three sizes of 5mm, 10mm and 15mm; the length range of the vertebral mounting block 5 is 30-50mm, the width range is 20-40mm, and the height range is 30-50mm. The vertebral mounting block 5 is set to a variety of sizes with a difference of 2mm, and is pre-manufactured for standby use. It is selected according to actual needs. The preferred length, width and height models include 30x20x30, 32x22x32, 34x24x34...50x40x50mm and other ten specifications;The length range of the connecting rod 3 is 50-60mm, the width range is 20-30mm, and the height range is 20-3mm. The connecting rod 3 is set to a variety of sizes with a difference of 2mm and is pre-manufactured for standby use. It can be selected according to actual needs. The preferred length, width and height models include five specifications: 50x20x20, 52x22x22, 54x24x24...60x30x30mm; this section of the scheme as a whole constitutes an iliac connection assembly for connecting the left and right iliac bones; during use, the threaded end of the first screw is passed through the third through hole and is threaded with the threaded mounting hole When the first screw is in a loose state, the connecting rod 3 can rotate, so that the two iliac connecting plates 1 can swing forward and backward at an angle. When the first screw is tightened, the adjusted connecting rod 3 is locked, thereby locking the iliac connecting plate 1 after the angle is adjusted. When the threaded end of the second screw passes through the fourth through hole and is threadedly matched with the threaded fixing hole, when the second screw is in a loose state, the rotating block 10 can rotate, so that the two iliac connecting plates 1 can swing up and down at an angle. When the second screw is tightened, the adjusted rotating block 10 is locked, thereby locking the iliac connecting plate 1 after the angle is adjusted. ;

[0036] To further explain, Figure 1 , Figure 2 and Figure 4As shown, in this embodiment, four fixing rings 7 are preferably included, and a plurality of positioning rods 2 are arranged on each fixing ring 7 at equal intervals in the circumferential direction. A plurality of through holes for the positioning rods 2 to pass through are provided on all rotating blocks 10 and the connecting blocks 4, and a plurality of blind holes for the positioning rods 2 to be inserted are provided on the two connecting rods 3 corresponding to all the through holes. In this embodiment, all the positioning rods 2 and all the fixing rings 7 are made of titanium alloy, and of course, stainless steel, titanium alloy or cobalt-based alloy can also be used; during use, when the connecting rod 3 is rotated, the blind holes on the connecting rod 3 are aligned with the through holes on the connecting block 4, and then the positioning rods 2 on the fixing ring 7 are inserted into the aligned blind holes and through holes, so that the positioning rods 2 lock the rotated connecting rod 3, and the fixing ring 7 is mounted on the first screw. When the first screw is tightened, the hexagonal end of the first screw will squeeze and fix the fixing ring 7 to prevent the positioning rod 2 from falling out; when the rotating block 10 is rotated, the through holes on the rotating block 10 are aligned with the blind holes on the connecting rod 3, and then Then, the positioning rod 2 on the other fixing ring 7 is inserted into the aligned blind hole and the through hole, so that the positioning rod 2 locks the rotating block 10 after rotation. By putting the fixing ring 7 on the second screw, when the second screw is tightened, the hexagonal end of the second screw will squeeze and fix the fixing ring 7 to prevent the positioning rod 2 from falling out. This section of the scheme as a whole constitutes a locking component for locking the rotating block 10 and the connecting rod 3 after rotation. Of course, the locking component can also use teeth and slots. A plurality of circularly distributed teeth are provided on the connecting surfaces of all connecting blocks 4 and all rotating blocks 10. Corresponding teeth are provided on the connecting surface of each connecting rod 3 with slots for engaging with the teeth. There are 24 teeth and slots, forming 24 "checkpoints". The connecting rod 3 rotates one checkpoint and the rotating block 10 rotates one checkpoint. The rotation angle is 15 degrees, which can be adjusted according to needs when installing the prosthesis. After the adjustment is completed, only the first screw and the second screw need to be tightened to lock the rotating connecting rod 3 and the rotating block 10 after rotation.

[0037] In actual use, half sacrum reconstruction or full sacrum reconstruction is selected according to the patient's sacrum resection. When half sacrum reconstruction is required, the lumbar vertebral body is connected to the top of a vertebral mounting block 5 by bone screws, and the bone screws are screwed into the lumbar vertebral body through the first screw hole from bottom to top, and the fusion layer 11 on the vertebral mounting block 5 is fitted with the cross section of half of the sacrum. The wavy grooves on the vertebral mounting block 5 can enhance stability, promote the adhesion, proliferation and differentiation of bone cells, and provide space for bone tissue growth. When full sacrum reconstruction is required, the positioning block 6 is engaged in the mounting grooves on the two positioning blocks 6, so that the two vertebral mounting blocks 5 are aligned and fitted in a mirror image, and the fusion layers 11 on the two vertebral mounting blocks 5 will fit and cooperate with each other, which can prevent the two vertebral mounting blocks 5 from being misaligned up and down; the angles of the two iliac connecting plates 1 are adjusted according to the angles of the osteotomy surfaces on the two iliums, and the two iliac connecting plates 1 can swing back and forth by rotating the connecting rod 3. Angle, and rotating the rotating block 10 can make the two iliac connecting plates 1 swing up and down, and align the blind holes on all connecting rods 3 with the perforations on the corresponding connecting blocks 4, and align the perforations on all rotating blocks 10 with the blind holes on the corresponding connecting rods 3. When the angle is adjusted, the positioning rods 2 on each corresponding fixing ring 7 are respectively installed in the aligned blind holes and perforations, so that the positioning rods 2 on each fixing ring 7 respectively lock each rotating rod 3 and each rotating block 10 after rotation, and then rotate the first screw to fix the two connecting rods 3 to the two connecting blocks 4 respectively, and lock the fixing rings 7 on the two connecting blocks 4 to prevent the positioning rods 2 from falling out; rotate the second screw to fix the two rotating blocks 10 to the two connecting rods 3 respectively, and lock the fixing rings 7 on the two rotating blocks 10 to prevent the positioning rods 2 from falling out; when the angle adjustment of all iliac connecting plates 1 is completed, the two iliac connecting plates 1 are fitted with the osteotomy surfaces on the left and right sides of the ilium, and fixed with bone screws.

[0038] Example 2

[0039] This embodiment further illustrates the technology. A metal sintered porous coating for improving bone ingrowth is formed on the top of each vertebral mounting block 5 and on the surface of each iliac connecting plate 1 that contacts the ilium. The metal sintered porous coating has a porosity of 30-50%, and a pore diameter of 100-600 μm. The metal sintered porous coating can provide good biological fixation, which helps to closely combine the prosthesis with the bone tissue. The rough surface of the metal sintered porous coating can increase the friction between the prosthesis and the bone, thereby improving the fixation effect. Secondly, due to the high porosity of the metal sintered porous coating, bone tissue can grow into the pores of the coating and form a stable combination with the prosthesis, which can not only improve the stability of the prosthesis, but also help the growth and repair of bones. In short, the application of the metal sintered porous coating on the prosthesis has multiple functions such as improving biological fixation and promoting bone growth and repair.

[0040] Example 3

[0041] This embodiment further illustrates the technology. A first size scale 8 is provided on all the connecting blocks 4. A first alignment line for aligning with the scale line on the first size scale 8 is provided on the front side walls of the two connecting rods 3. A second size scale 9 is provided on all the rotating blocks 10. A second alignment line for aligning with the scale line on the second size scale 9 is provided on the front side walls of the two connecting rods 3. The number of scale lines on the first size scale 8 and the second size scale 9 is the same as the number of positioning rods 2 on each fixing ring 7, which is 24. The scale lines on the first size scale 8 and the second size scale 9 are respectively aligned with the corresponding positioning rods 2 on the fixing ring 7. The angle between adjacent scale lines on the first size scale 8 and the second size scale 9 is 15 degrees. During the reconstruction of the entire sacrum, the alignment of the first size scale 8 on the left and right sides with the first alignment line and the alignment of the second size scale 9 with the second alignment line can be observed to confirm whether the two iliac connection plates 1 are in a symmetrical state, so that the doctor can quickly adjust the angles of the two iliac connection plates 1.

Claims

1. A modular sacral reconstruction prosthesis, characterized in that: The invention comprises two vertebral mounting blocks (5) which are symmetrically distributed and fit together, a positioning block (6) is arranged between the two vertebral mounting blocks (5), mounting grooves for independently engaging the positioning blocks (6) are provided on the two vertebral mounting blocks (5), fusion layers (11) are provided on the fit surfaces of the two vertebral mounting blocks (5), and the two fusion layers (11) are provided with mutually matching wave-shaped grooves; symmetrically distributed and mutually fit connecting blocks (4) are fixed at the bottom of the two vertebral mounting blocks (5), the two connecting blocks (4) are fixed by screws, and iliac connecting components for connecting the left and right iliac bones are detachably installed on the two connecting blocks (4).

2. The modular sacral reconstruction prosthesis according to claim 1, characterized in that: The iliac connection assembly comprises two iliac connection plates (1), the two connection blocks (4) are respectively detachably mounted with freely rotatable and mutually symmetrical connection rods (3), the front side walls of the unconnected ends of the two connection rods (3) are respectively detachably mounted with freely rotatable rotating blocks (10), all the connection blocks (4) and all the rotating blocks (10) are respectively provided with locking assemblies for respectively locking the rotating blocks (10) and the connection rods (3) after rotation, and the two iliac connection plates (1) are symmetrically distributed and respectively fixed to the two rotating blocks (10).

3. The modular sacral reconstruction prosthesis according to claim 2, characterized in that: The top of each vertebral mounting block (5) and the surface of each iliac connection plate (1) that contacts the ilium are both formed with a metal sintered porous coating for improving the bone ingrowth effect.

4. The modular sacral reconstruction prosthesis according to claim 3, characterized in that: The porosity of the metal sintered porous coating is 30-50%, and the pore diameter of the metal sintered porous coating is 100-600 μm.

5. The modular sacral reconstruction prosthesis according to claim 2, characterized in that: The thickness of the iliac connection plate (1) is 5-15 mm.

6. The modular sacral reconstruction prosthesis according to claim 2, characterized in that: The locking assembly comprises four fixing rings (7), each fixing ring (7) being provided with a plurality of positioning rods (2) at equal intervals in the circumferential direction, all rotating blocks (10) and connecting blocks (4) being provided with a plurality of through holes for the positioning rods (2) to pass through, and corresponding to all the through holes, a plurality of mounting holes for the positioning rods (2) to be inserted are provided on the two connecting rods (3).

7. The modular sacral reconstruction prosthesis according to claim 6, characterized in that: All the connecting blocks (4) are provided with a first size scale (8), the front side walls of the two connecting rods (3) are provided with a first alignment line for aligning with the scale line on the first size scale (8), all the rotating blocks (10) are provided with a second size scale (9), and the front side walls of the two connecting rods (3) are provided with a second alignment line for aligning with the scale line on the second size scale (9).

8. The modular sacral reconstruction prosthesis according to claim 6, characterized in that: The positioning rod (2) is made of titanium alloy.

9. The modular sacral reconstruction prosthesis according to claim 1, characterized in that: The fusion layer (11) is a metal sintered porous coating.

10. The modular sacral reconstruction prosthesis according to claim 9, characterized in that: The porosity of the metal sintered porous coating is 30-50%, and the pore diameter of the metal sintered porous coating is 100-600 μm.

11. The modular sacral reconstruction prosthesis according to claim 1, characterized in that: The positioning block (6) is made of titanium alloy.

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