A custom sleeve prosthesis for bone tumor revision

Abstract

The present invention belongs to the field of medical devices, and provides a customized sleeve prosthesis for bone tumor revision, comprising a three-leaf sleeve rod, wherein the three-leaf sleeve rod comprises a three-leaf fixing plate and a backbone extension section, wherein the inner surface of the three-leaf fixing plate abuts against the outer surface of the natural bone segment for fixing the natural bone segment, wherein the three-leaf fixing plate is provided with a locking fixture, and the three-leaf fixing plate is preliminarily fixed to the natural bone segment through the locking fixture, wherein one end of the backbone extension section close to the three-leaf fixing plate is provided with a medullary needle sleeve with a central reserved middle hole, wherein the middle hole of the medullary needle sleeve is reserved for the placement of a residual medullary needle, wherein the backbone extension section also comprises a backbone prosthesis, wherein the other end of the backbone prosthesis is a first cone connecting end of a cone structure, wherein the medullary needle sleeve reserves the middle hole, and utilizes the original residual implant prosthesis to maintain stability, wherein the scope of application is widened to include knee joint and hip joint revision, and the extension rod can be flexibly assembled.

Description

Technical Field

[0001] The invention relates to the technical field of medical instruments, and in particular to a customized sleeve prosthesis for bone tumor revision. Background Art

[0002] Artificial customized tumor prosthesis replacement has become an important method for functional reconstruction of bone tumor resection during limb-saving surgery. With the increase in the number of prostheses used and the extension of their service life, the possibility of customized tumor prostheses breaking is increasing. Unlike modular prostheses, which can only replace the broken part after breaking, when a customized tumor prosthesis is broken, it is generally necessary to replace the entire prosthesis when it is revised. However, when the prosthesis breaks, if the medullary pins in the remaining body are of sufficient length and the part in the medullary cavity is not loose, it is also difficult to remove it. Summary of the invention

[0003] The purpose of the present invention is to propose a customized sleeve prosthesis with a simple structure for bone tumor revision, which can solve the technical problems existing in the prior art, has a wider scope of application including knee and hip joint revision, and can utilize the original residual implant prosthesis and be flexibly assembled.

[0004] The technical solution of the present invention is: a customized sleeve prosthesis for bone tumor revision includes a three-leaf sleeve rod, the three-leaf sleeve rod includes a three-leaf fixing plate and a backbone extension section, the inner surface of the three-leaf fixing plate abuts the outer surface of the natural bone segment for fixing the natural bone segment, the three-leaf fixing plate is provided with a locking fixture, and the three-leaf fixing plate is preliminarily fixed to the natural bone segment through the locking fixture; the end of the backbone extension section close to the three-leaf fixing plate is a medullary needle sleeve with a central reserved middle hole, the middle hole of the medullary needle sleeve is reserved for the placement of residual medullary needles, the backbone extension section also includes a backbone prosthesis, the other end of the backbone prosthesis is connected to the first cone connecting end of the cone structure, the medullary needle sleeve reserves the middle hole, and uses the original residual implant prosthesis to maintain stability.

[0005] The extension rod can be designed to extend its length according to the length of the defect. When the extension rod needs to be used for extension, the first cone connecting end of the three-leaf sleeve rod is cone-connected to the groove connecting end of the extension rod, and the length of the extension rod is configured according to the length of the defect.

[0006] The end of the backbone prosthesis connected to the first cone connecting end is provided with a stepped first fixing portion, and the raised portion on the groove connecting end is clamped on the first fixing portion for connection and circumferential fixation. The other end of the extension rod is provided with a second fixing portion, and the second fixing portion is a cylinder with a groove provided circumferentially, and the second cone connecting end is connected to the groove connecting end via the second fixing portion.

[0007] The three-leaf fixation plate is provided with a trabecular bone structure, and secondary fixation is performed through the porous trabecular bone structure on the three-leaf fixation plate. The trabecular bone can promote bone ingrowth.

[0008] The three-leaf fixing plate is provided with a plurality of locking threaded holes, which are initially fixed to the natural bone segment by means of locking screws.

[0009] The diaphyseal prosthesis includes diaphyseal prosthesis part one, diaphyseal prosthesis part two, diaphyseal prosthesis part three and a first fixing part. The diaphyseal prosthesis part one, diaphyseal prosthesis part two and diaphyseal prosthesis part three constitute the medullary needle sleeve. The outer diameters of diaphyseal prosthesis part one and diaphyseal prosthesis part two are larger than the outer diameters of diaphyseal prosthesis part three and the first fixing part. The space surrounded by diaphyseal prosthesis part one and the three-leaf fixing plate can accommodate natural bone segments. The side surface of diaphyseal prosthesis part two is provided with a prosthesis positioning surface 12, which is a cutting surface of diaphyseal prosthesis part two and is used to determine the installation and machining positioning direction of the prosthesis. The side surface of diaphyseal prosthesis part two is provided with a prosthesis positioning surface, which is a cylindrical cutting surface and is used to determine the installation and machining positioning direction of the prosthesis.

[0010] The outer diameter of the first part of the diaphyseal prosthesis is 2mm-3mm larger than the outer diameter of the natural bone segment in contact, a first chamfer is provided at the connection between the second cone connection end and the second fixing part, and a second chamfer is provided at the upper end of the second part of the diaphyseal prosthesis.

[0011] The second chamfer is to ensure that it can be installed in the end. If it is a right angle without this chamfer, processing is very difficult and requires special tools. At the same time, adding the second chamfer in the diameter transition area (that is, the diameter changes from large to small at the connection between the second part of the backbone prosthesis and the third part of the backbone prosthesis) can reduce stress concentration and increase the rigidity of the cone structure of the first cone connection end. At the same time, it is easy to process and has a certain guiding role in installation.

[0012] The three-leaf fixation plate is positioned and designed according to the CT data reconstruction model, and its surface is highly adapted to the natural bone. The inner diameter of the medullary needle sleeve is 1mm-3mm larger than the diameter of the residual medullary needle.

[0013] The residual medullary pins are fixed by bone water, and each plate of the three-leaf fixing plate is provided with reinforcing ribs for increasing the strength of the three-leaf fixing plate.

[0014] The first cone connection end is connected to the revised femoral condyle or femoral stem or extension rod.

[0015] The advantages and positive effects of the present invention are as follows: due to the adoption of the above technical scheme, the application scope of a customized sleeve prosthesis for bone tumor revision is widened, including knee and hip joint revision; a middle hole is reserved in the medullary needle sleeve, and the original residual implant prosthesis is used to maintain stability; the three-leaf fixation plate is a porous structure, and the strength is increased by reinforcing ribs, and the porous structure can directly observe the bone ingrowth; the prosthesis positioning surface can more intuitively observe the prosthesis installation positioning, saving operation time, and the prosthesis positioning surface can be used as a thread processing positioning reference; adding an extension rod can be flexibly assembled according to the 3D size range of the part and the defect length. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of a three-leaf sleeve rod in a specific embodiment of a customized sleeve prosthesis for bone tumor revision of the present invention;

[0017] Figure 2 It is a schematic diagram of the extension rod structure of a specific embodiment of a customized sleeve prosthesis for bone tumor revision of the present invention;

[0018] Figure 3 It is a schematic diagram of the femoral condyle structure of a specific embodiment of a customized sleeve prosthesis for bone tumor revision of the present invention;

[0019] Figure 4 It is a schematic diagram of the structure of a femoral stem of a customized sleeve prosthesis for bone tumor revision according to a specific embodiment of the present invention;

[0020] Figure 5 It is a schematic diagram of a proximal femoral revision structure of a customized sleeve prosthesis for bone tumor revision according to a specific embodiment of the present invention;

[0021] Figure 6 It is a schematic diagram of a distal femoral revision structure of a customized sleeve prosthesis for bone tumor revision according to a specific embodiment of the present invention.

[0022] In the figure:

[0023] 1. Three-leaf fixation plate; 2. Shaft extension section; 3. Locking threaded hole; 4. Trabeculae; 5. Medullary needle sleeve; 6. Shaft prosthesis; 7. First cone connection end; 8. Extension rod; 9. First chamfer; 10. Second chamfer; 11. First fixing part; 12. Prosthesis positioning surface; 13. Groove connection end; 14. Second fixing part; 15. Second cone connection end; 16. Reinforcement rib; 17. Femoral condyle; 18. Femoral stem; 61. Shaft prosthesis part one; 62. Shaft prosthesis part two; 63. Shaft prosthesis part three. DETAILED DESCRIPTION

[0024] Specific embodiment: Figure 1-6The invention discloses a customized sleeve prosthesis for bone tumor revision. When a customized tumor prosthesis is broken, the whole prosthesis generally needs to be replaced. When the prosthesis is broken, if the medullary pins in the remaining body are long enough and the part in the medullary cavity is not loose, it is difficult to remove it. The remaining prosthesis part can be used.

[0025] The scope of application of this application: artificial tumor prosthesis revision, including revision after distal femoral knee joint prosthesis fracture and revision after proximal femoral hip joint prosthesis fracture.

[0026] The invention discloses a customized sleeve prosthesis for bone tumor revision, comprising a three-leaf sleeve rod such as Figure 1As shown, the three-leaf sleeve rod includes a three-leaf fixing plate 1 and a backbone extension section 2, the three-leaf fixing plate 1 is connected to the natural bone segment, the inner surface of the three-leaf fixing plate 1 abuts the outer surface of the natural bone segment for fixing the natural bone segment, the three-leaf fixing plate 1 is provided with a locking fixing piece, the fixing plates in the three-leaf fixing plate 1 in this specific embodiment are evenly distributed along the circumference of the cross section at the connection with the backbone extension section 2, the locking fixing piece is a locking threaded hole 3 on the three-leaf fixing plate 1 and a locking screw matched therewith, and a preliminary fixation is performed with the natural bone segment by means of the locking screw, and a plurality of the locking threaded holes 3 on each of the three-leaf fixing plates 1 are provided, and in this specific implementation, the locking threaded holes 3 are evenly distributed on each of the three-leaf fixing plates 1 along the axis of the three-leaf fixing plate 1, the three-leaf fixing plate 1 is provided with a trabecular bone 4 structure, and secondary fixation is performed by means of the porous trabecular bone 4 structure on the three-leaf fixing plate 1, and the trabecular bone 4 can promote bone ingrowth, and the three-leaf fixing plate 1 is provided with a trabecular bone 4 structure according to CT. The data reconstruction model is positioned and designed, and the surface is highly adapted to the natural bone; the backbone extension section 2 includes a backbone prosthesis 6 and a first cone connecting end 7 connected to the other end of the backbone prosthesis, the backbone prosthesis 6 includes a backbone prosthesis part 1 61, a backbone prosthesis part 2 62, a backbone prosthesis part 3 63 and a first fixing part 11, and the backbone extension section 2 in this specific embodiment is provided with the backbone prosthesis part 1 61, the backbone prosthesis part 2 62, the backbone prosthesis part 3 63 and the first fixing part 11 in sequence from one end close to the three-leaf fixing plate 1 The prosthesis part 3 63 and the first fixing part 11, the backbone prosthesis part 1 61, the backbone prosthesis part 2 62 and the backbone prosthesis part 3 63 constitute a medullary needle sleeve 5, the medullary needle sleeve 5 is arranged at one end close to the three-leaf fixing plate 1 and a middle hole is reserved in the center, which is the placement area of ​​the residual medullary needle. The middle hole of the medullary needle sleeve 5 is reserved for the placement of the residual medullary needle. The backbone prosthesis part 1 61 is distributed with a porous trabecular bone 4 structure, and the trabecular bone 4 is in contact with the cross-section of the natural bone segment, which is conducive to bone ingrowth. The depth of the middle hole of the medullary needle sleeve 5 is set according to the length of the residual medullary needle, which is 1mm-3mm longer than the length of the residual medullary needle. The diameter of the middle hole is 1mm-3mm longer than the diameter of the residual medullary needle. The medullary needle sleeve 5 is a hollow cylinder with a stepped outer surface. The outer diameters of the first and second diaphyseal prosthesis parts 61 and 62 are the same and larger than the third diaphyseal prosthesis part 63 and the first fixing part 11. The outer diameter of the third diaphyseal prosthesis part 63 is 24mm-32mm, which is generally designed according to the size of the patient's bones and is 2mm-3mm larger than the diameter of the natural bone segment. The outer diameter of the first diaphyseal prosthesis part 61 is 2mm-3mm larger than the outer diameter of the natural bone segment in contact with it, so that the space enclosed by the first diaphyseal prosthesis part 61 and the three-leaf fixing plate 1 can accommodate the natural bone segment, and at the same time, the purpose of overall weight reduction is achieved on the basis of ensuring the strength of use. The outer diameter of the diaphyseal prosthesis 6 is larger than the contact surface of the natural bone segment to prevent the prosthesis from being too thin to be inserted into the bone.The outer diameters of the first diaphyseal prosthesis 61 and the second diaphyseal prosthesis 62 may also be different. The outer diameters of the first diaphyseal prosthesis 61 and the third diaphyseal prosthesis 63 are different, but the effect of ensuring that the contact surface with the natural bone segment is larger than that of the natural bone segment is guaranteed. From the experimental results, this design is simple to process and has strong practicality. The residual medullary needle is fixed in the medullary needle sleeve 5 by bone water.

[0027] The other end of the diaphyseal prosthesis 6 is a first cone connecting end 7 of a cone structure, which is connected to the renovated femoral condyle, femoral stem 18 or extension rod 8. The middle hole is reserved in the medullary needle sleeve 5, and the original residual implant prosthesis is used to maintain stability.

[0028] The upper end of the second part 62 of the diaphyseal prosthesis, that is, the end of the second part 62 of the diaphyseal prosthesis away from the three-leaf fixing plate 1, is provided with a second chamfer 10. The second chamfer 10 is to ensure that it can be installed in the end. If it is a right angle without this chamfer, it is very difficult to process and requires special tools. At the same time, adding the second chamfer 10 in the diameter transition area (that is, the diameter changes from large to small at the connection between the second part 62 of the diaphyseal prosthesis and the third part 63 of the diaphyseal prosthesis) can reduce stress concentration, increase the rigidity of the cone structure of the first cone connection end 7, and facilitate processing. It also has a certain guiding role during installation. The side of the second part of the diaphyseal prosthesis is provided with a prosthesis positioning surface 12, which is a cylindrical cutting surface and is used to determine the installation and machining positioning direction of the prosthesis. The prosthesis positioning surface 12 can more intuitively observe the prosthesis installation positioning, save surgical time, and install the meaning of the directional mark. The first cone connection end 7 can also be provided with a chamfer near the first fixing part 11. The prosthesis positioning surface 12 can be used as a thread processing positioning reference. The prosthesis positioning surface 12 is used as the reference surface for machining, and all machining is based on it; if there is no prosthesis positioning surface 12, it is generally necessary to add an additional reference and then cut it off, which is time-consuming and labor-intensive. Figure 2As shown, the extension rod 8 can be extended in length according to the length of the defect. When the three-leaf sleeve rod needs to use the extension rod 8, the first cone connecting end 7 of the three-leaf sleeve rod is cone-connected with the groove connecting end 13 of the extension rod 8. The end of the backbone prosthesis 6 connected to the first cone connecting end 7 is provided with a first fixing portion 11. The first fixing portion 11 is a cylinder with a groove in the circumferential direction. The raised portion on the groove connecting end 13 is clamped in the groove of the first fixing portion 11 to play a role of connection and circumferential fixation. The clamping shapes of the first fixing portion 11 and the groove connecting end 13 match to prevent circumferential rotation after clamping. The other end of the extension rod 8 is provided with a second fixing portion 1 4, the second fixing part 14 is a cylinder with a groove in the circumference, the second cone connection end 15 is connected to the groove connection end 13 through the second fixing part 14, and the second cone connection end 15 and the second fixing part 14 are connected at a first chamfer 9, the first chamfer 9 facilitates the connection of the extension rod 8 with the femoral stem 18 or the femoral condyle 17 and other parts, and completes the proximal femoral revision and the distal femoral revision according to the different parts connected to the femoral stem 18 or the femoral condyle 17, the first chamfer 9 has a similar function to the second chamfer 10, and at the same time has an installation guide, and can also play a role in reducing stress concentration and strengthening the strength of the extension rod 8, considering that the 3D printing space is limited. The extension rod 8 can also be a standard part of 3D printing or machining; it is connected through a cone to meet the needs of the knee joint and hip joint, where the knee joint and hip joint are machined parts.

[0029] When a custom-made tumor prosthesis is broken, the entire prosthesis generally needs to be replaced. When the prosthesis is broken, if the medullary pins in the remaining body are long enough and the part in the medullary cavity is not loose, it is difficult to remove it, and the remaining part of the prosthesis can be used.

[0030] Its application scope is artificial tumor prosthesis revision, including revision after distal femoral knee joint prosthesis fracture and revision after proximal femoral hip joint prosthesis fracture. When the distal femoral knee joint prosthesis is fractured and revised, the three-leaf sleeve rod can be connected to the femoral condyle 17. The femoral condyle 17 is as follows: Figure 3 As shown, the femoral condyle 17 at the connection is provided with a bayonet adapted to the first cone connection end 7 on the three-leaf sleeve rod or the second cone connection end 15 of the extension rod 8. The structure of the distal femur after revision is as shown in FIG. Figure 6 When the proximal femoral hip prosthesis is repaired after fracture, the three-leaf sleeve rod can be connected to the femoral stem 18, and the femoral stem 18 is as shown in FIG. Figure 4 As shown, the femoral stem 18 at the connection is provided with a bayonet adapted to the first cone connection end 7 on the three-leaf sleeve rod or the second cone connection end 15 of the extension rod 8, and the proximal femoral hip joint prosthesis is repaired after fracture. Figure 5As shown, whether the three-leaf sleeve rod is connected to the femoral condyle 17 or the femoral stem 18 through the extension rod 8 depends on the degree of the patient's femoral defect. Adding the extension rod 8 can be flexibly assembled according to the 3D size range of the parts and the defect length, which is more flexible and has a longer service life.

[0031] The first diaphyseal prosthesis part 61, the second diaphyseal prosthesis part 62, the third diaphyseal prosthesis part 63, the first fixing part 11 and the first cone connecting end 7 may be an integral structure.

[0032] Surgical method: remove the broken movable part of the original prosthesis to expose the remaining medullary needle. All components of the prosthesis are assembled in advance. When implanting, insert the remaining medullary needle into the middle hole of the medullary needle sleeve 5 and fix it with bone cement. The three-leaf fixation plate 1 is attached to the natural bone, and the locking screw is driven into the locking threaded hole 3 to fix it, and the operation is completed.

[0033] The diameter of the middle hole of the medullary needle sleeve 5 is increased by 1-3 mm according to the diameter of the residual medullary needle, and the length is increased by 1-3 mm.

[0034] The length of the three-leaf fixing plate 1 is between 60mm and 120mm, and the number of locking threaded holes 3 is evenly distributed on the three-leaf fixing plate 1 along the axial direction of the three-leaf fixing plate 1 according to the length, and each locking threaded hole 3 is spaced 15-20mm apart. The width of the three-leaf fixing plate 1 is 12-20mm, and the three-leaf fixing plate 1 contacts the curved surface of the natural bone over a large area, which increases the adhesion and ensures easy installation. Solid reinforcement ribs 16 are distributed on the three-leaf fixing plate 1. The solid reinforcement ribs 16 are distributed axially on each plate of the three-leaf fixing plate 1 along each plate of the three-leaf fixing plate 1, and the solid reinforcement ribs 16 are located on the line connecting the centers of the locking threaded holes 3. It is more optimized that multiple solid reinforcement ribs 16 can be provided on each plate of the three-leaf fixing plate 1, and the solid reinforcement ribs 16 are located on the line connecting the centers of the locking threaded holes 3. A first solid reinforcement rib is provided on the solid reinforcement rib 16, and each locking threaded hole 3 is provided with a second solid reinforcement rib perpendicular to the first solid reinforcement rib.

[0035] Hydroxyapatite is sprayed on the porous trabecular structure 4 to increase the surface activity and promote bone ingrowth. The three-leaf fixation plate 1 is a porous structure, and the strength is increased by using solid reinforcing ribs 16. The porous structure can visually observe the bone ingrowth.

[0036] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A custom sleeve prosthesis for bone tumor revision, characterized in that: The invention comprises a three-leaf sleeve rod, wherein the three-leaf sleeve rod comprises a three-leaf fixing plate and a backbone extension section, wherein the inner surface of the three-leaf fixing plate abuts against the outer surface of the natural bone segment for fixing the natural bone segment, and the three-leaf fixing plate is provided with a locking fixing piece, which is used for preliminary fixation with the natural bone segment; the end of the backbone extension section close to the three-leaf fixing plate is a medullary needle sleeve with a central reserved middle hole, and the middle hole of the medullary needle sleeve is a space reserved for placing the residual medullary needle, and the backbone extension section also comprises a backbone prosthesis, and the other end of the backbone prosthesis is connected to the first cone connecting end of the cone structure, and the medullary needle sleeve reserves the middle hole, and utilizes the original residual implant prosthesis to maintain stability, and the backbone prosthesis comprises a first backbone prosthesis part, a second backbone prosthesis part, a third backbone prosthesis part and a first fixing part, and the first backbone prosthesis part, the second backbone prosthesis part and the third backbone prosthesis part constitute the medullary needle sleeve.

2. A customized sleeve prosthesis for bone tumor revision according to claim 1, characterized in that: The customized sleeve prosthesis also includes an extension rod, the first cone connection end of the three-leaf sleeve rod is cone-connected to the groove connection end of the extension rod, and the length of the extension rod is configured according to the defect length.

3. A customized sleeve prosthesis for bone tumor revision according to claim 2, characterized in that: A first fixing portion is provided at one end of the prosthesis connected to the first cone connecting end, and the raised portion on the groove connecting end is clamped on the first fixing portion for connection and circumferential fixation. A second fixing portion is provided at the other end of the extension rod, and the second fixing portion is a cylinder with a groove provided circumferentially, and the second cone connecting end is connected to the groove connecting end via the second fixing portion.

4. A customized sleeve prosthesis for bone tumor revision according to claim 3, characterized in that: The three-leaf fixation plate is provided with a trabecular bone structure, and secondary fixation is performed through the porous trabecular bone structure on the three-leaf fixation plate. The trabecular bone can promote bone ingrowth.

5. A customized sleeve prosthesis for bone tumor revision according to claim 4, characterized in that: The three-leaf fixing plate is provided with a plurality of locking threaded holes, which are initially fixed to the natural bone segment by means of locking screws.

6. A customized sleeve prosthesis for bone tumor revision according to claim 5, characterized in that: The outer diameters of the first and second diaphyseal prosthesis parts are both larger than the outer diameters of the third diaphyseal prosthesis part and the first fixing part. The space enclosed by the first diaphyseal prosthesis part and the three-leaf fixing plate can accommodate natural bone segments. The side surface of the second diaphyseal prosthesis part is provided with a prosthesis positioning surface, which is the cutting surface of the second diaphyseal prosthesis part and is used to determine the installation and machining positioning direction of the prosthesis.

7. A customized sleeve prosthesis for bone tumor revision according to claim 6, characterized in that: The outer diameter of the first part of the diaphyseal prosthesis is 2mm-3mm larger than the outer diameter of the natural bone segment in contact, a first chamfer is provided at the connection between the second cone connection end and the second fixing part, and a second chamfer is provided at the upper end of the second part of the diaphyseal prosthesis.

8. A customized sleeve prosthesis for bone tumor revision according to claim 7, characterized in that: The three-leaf fixation plate is positioned and designed according to the model reconstructed from CT data, and its surface is highly adapted to the natural bone. The inner diameter of the medullary needle sleeve is 1 mm to 3 mm larger than the diameter of the residual medullary needle.

9. A customized sleeve prosthesis for bone tumor revision according to claim 8, characterized in that: The residual medullary pin is fixed by bone cement, and each plate of the three-leaf fixation plate is provided with reinforcing ribs for increasing the strength of the three-leaf fixation plate.

10. The customized sleeve prosthesis for bone tumor revision according to claim 2, characterized in that: The first cone connection end is connected to the revised femoral condyle or femoral stem or extension rod.

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