Femoral implant biomechanical test assembly method

Abstract

The invention provides a femoral implant biomechanical test assembly method, and belongs to the technical field of bone implant test. Comprising the following steps: fixing a sawbone by using a fixing mechanism, establishing coordinates and adjusting the position of the sawbone according to the coordinates, simulating implantation of a bone fracture plate and a screw by using software, drilling according to a simulation result, fixing the bone fracture plate and the screw, cutting a fracture line on the sawbone by using a cutting mechanism, and embedding by using denture powder after a bone implant is implanted. And the embedding tool is connected to the two ends of the sawbone, and assembling is completed. Calibration of the positions of the real object and the three-dimensional model is achieved through the coordinate points, the three-dimensional model is reversely pushed to the assembly position of the screw and the bone fracture plate, the difference between a real object assembly structure and a three-dimensional model assembly structure can be greatly reduced, errors caused by manual assembly are avoided, and the preciseness of biomechanical testing can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of bone implant testing, and in particular to a femoral implant biomechanical testing and assembling method. Background Art

[0002] At present, the common method for studying the biomechanics of femoral implants in vitro is to implant the implant into the sawbone bone. Since the implant and the sawbone bone lack a reference during the assembly process, each assembly sample has a large error, which makes the biomechanical test results also have inevitable errors, affecting the judgment of doctors and researchers on the performance of the implant. To this end, the present invention provides a femoral implant biomechanical test assembly method. Summary of the invention

[0003] The purpose of the invention is to provide a biomechanical testing and assembling method for a femoral implant.

[0004] To solve the above technical problems, the purpose of the present invention is achieved as follows:

[0005] A femoral implant biomechanical testing assembly method comprises the following steps:

[0006] S1: fix the sawbone using a fixation mechanism;

[0007] S2: Attach 3D scanning points to the apex of the femoral head, the apex of the greater trochanter and the midpoint of the condylar fossa of the sawbone, and make the actual coordinate system of the sawbone through 3D scanning. Compare the actual coordinate system with the coordinate system of the sawbone 3D model in the 3D software. If there is a deviation, adjust the position of the sawbone through the fixing mechanism until the actual coordinate system coincides with the coordinate system of the 3D model.

[0008] S3: assembling the three-dimensional model of the bone plate and the three-dimensional model of the bone plate fixing screw onto the three-dimensional model of the sawbone bone in the three-dimensional software, and extracting the axis of the assembled three-dimensional model of the screw;

[0009] S4: driving the drilling mechanism to drill the sawbone according to the axis in step S3;

[0010] S5: fixing the bone plate and the bone plate fixing screws to the sawbone corresponding to the holes drilled in step S4;

[0011] S6: using the cutting mechanism to cut a fracture line on the sawbone bone;

[0012] S7: Fixing the remaining bone plates or the remaining screws on the sawbone corresponding to the holes drilled in step S4;

[0013] S8: After the bone implant is implanted, the fixing mechanism drives the sawbone to move so that the inclination angles of the femoral force line in the coronal and sagittal planes meet the test requirements, and the implant is embedded with dental tray powder to connect the embedding tooling to both ends of the sawbone.

[0014] The fixing mechanism comprises a fixing ring and a connecting seat; the fixing ring is connected to the connecting seat through a connecting rod, and an inflatable clamping mechanism is arranged inside; the fixing ring can rotate along its axial direction and can also rotate along the axial direction of the connecting rod; the fixing ring and the connecting seat can move left and right;

[0015] The drilling mechanism comprises a first arc-shaped slide rail and a second arc-shaped slide rail; the second arc-shaped slide rail is slidably arranged on the inner side surface of the first arc-shaped slide rail, and a telescopic rod is slidably arranged on the inner side surface; the end of the telescopic rod is detachably connected to a drill bit.

[0016] On the basis of the above solution and as a preferred solution of the above solution, the fixing ring is sleeved in the middle position of the sawbone when fixing the sawbone.

[0017] On the basis of the above scheme and as a preferred scheme of the above scheme, the remaining bone plates in step S7 include auxiliary bone plates fixed on the opposite side of the bone plates; the remaining screws include the auxiliary bone plate fixing screws and cancellous bone screws.

[0018] On the basis of the above scheme and as a preferred scheme of the above scheme, an actively rotatable mounting seat is provided at the end of the telescopic rod; a mounting groove is provided at the center of the mounting seat; slots passing through the mounting seat are provided on both sides of the mounting groove, and a magnetic attraction portion is provided at the bottom of the mounting groove; a mounting head matching the mounting groove is provided at the end of the drill bit; limit blocks matching the slots are provided on both sides of the mounting head, and a magnetic attraction portion is provided at the end of the mounting head.

[0019] On the basis of the above scheme and as a preferred scheme of the above scheme, the cutting mechanism includes two sliding rods; a base is slidably arranged on the sliding rods; a slide groove is opened in the base; a cutter and a cam are arranged in the slide groove; the cutter is of a rectangular structure, with cutting teeth arranged at the first end and the second end slidably connected in the slide groove; there are two cams, which are respectively arranged on the upper and lower sides of the cutter, and abut against the edge of the cutter, so as to drive the cutter to slide up and down in the slide groove.

[0020] The beneficial effects of the present invention are:

[0021] 1. Fix the sawbone through the assembly system, import the position of the physical sawbone into the 3D software through 3D scanning, and compare the coordinates of the 3D model of the sawbone in the 3D software to obtain the position difference between the physical object and the model. Then, the physical sawbone is driven by the fixing mechanism of the assembly system to reach the same position as the 3D model of the sawbone, so as to ensure the accuracy of subsequent processing and assembly.

[0022] 2. The axis of each screw is obtained by reverse-guiding the 3D model of the bone plate and the bone plate fixing screws in the 3D software. The control device controls the drilling mechanism of the assembly system to drill holes on the physical sawbone according to the axis of each screw to ensure that the structure of the physical object is the same as that of the 3D model and maintain the accuracy of the test. At the same time, the installation position of the physical screw can be reversed by 3D to avoid cross interference of the screws during manual installation.

[0023] 3. The present invention realizes the calibration of the position of the real object and the three-dimensional model through coordinate points, and reversely pushes to the assembly position of the screw and the bone plate through the three-dimensional model, which can greatly reduce the difference between the assembly structure of the real object and the assembly structure of the three-dimensional model, avoid the errors caused by manual assembly, and improve the rigor of biomechanical testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the cooperation between the fixing mechanism of the present invention and the sawbone.

[0025] Figure 2 This is a schematic diagram of the sawbone and its various mechanisms of the present invention.

[0026] Figure 3 It is a schematic diagram of the drilling mechanism structure of the present invention.

[0027] Figure 4 It is a schematic diagram of the cutting mechanism structure of the present invention.

[0028] Figure 5 It is an exploded schematic diagram of the cutting mechanism of the present invention.

[0029] Figure 6 It is a structural schematic diagram of the drill bit and the mounting seat of the present invention.

[0030] Figure 7 It is a schematic diagram of the embedding tooling structure of the present invention.

[0031] Figure 8 It is a schematic diagram of the present invention after being assembled.

[0032] In the figure: 1, sawbone; 2, bone plate; 3, bone plate fixing screw; 4, embedded tooling; 11, fixing ring; 12, connecting seat; 13, connecting rod; 21, first arc-shaped slide rail; 22, second arc-shaped slide rail; 23, telescopic rod; 24, drill bit; 25, mounting head; 26, mounting seat; 31, sliding rod; 32, base; 33, cutter; 34, cam. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0034] A femoral implant biomechanical testing assembly method comprises the following steps:

[0035] S1: Fixing the sawbone 1 with a fixing mechanism to adjust the position of the sawbone 1 and process it. Figure 1 and Figure 2 As shown, the fixing mechanism includes a fixing ring 11 and a connecting seat 12. The fixing ring 11 is connected to the connecting seat 12 through a connecting rod 13. An inflatable clamping mechanism is arranged inside. The inflatable clamping mechanism expands after being inflated to clamp the sawbone 1. Since the inflatable clamping mechanism is relatively soft in texture, it does not damage the sawbone 1. At the same time. The inflation amount of the inflatable clamping mechanism is adjustable, and the clamping degree can be changed. The fixing ring 11 can rotate along its axial direction, and can drive the sawbone 1 to rotate along its axis to adjust its position. At the same time, the fixing ring 11 can rotate axially along the connecting rod 13, and can change the inclination angle of the sawbone 1. In addition, the fixing ring 11 and the connecting seat 12 can move left and right to adjust the water level position of the sawbone 1.

[0036] S2: 3D scanning points are attached to the apex of the femoral head, the apex of the greater trochanter and the midpoint of the condylar fossa of the sawbone 1. The position information of the real sawbone 1 is imported into the software through 3D scanning, and the actual coordinate system of the sawbone is made. The actual coordinate system is compared with the coordinate system of the sawbone 3D model in the 3D software. If there is a deviation, the position of the sawbone 1 is adjusted through the fixing mechanism until the actual coordinate system coincides with the 3D model coordinate system to ensure that the position arrangement of the real sawbone 1 and the 3D model of the sawbone are the same.

[0037] S3: Assemble the three-dimensional model of the bone plate and the three-dimensional model of the bone plate fixing screws onto the three-dimensional model of the sawbone bone in the three-dimensional software, and extract the axis of the assembled three-dimensional model of the screws to determine the implantation position of each screw in the real object.

[0038] S4: According to the screw axis extracted in step S3, drive the drilling mechanism to drill the sawbone to obtain a plurality of screw implantation holes. Figure 3 As shown, the drilling mechanism includes a first arc-shaped slide rail 21 and a second arc-shaped slide rail 22. The first arc-top slide rail 21 is relatively fixed, and the second arc-shaped slide rail 22 is slidably arranged on the inner side of the first arc-shaped slide rail 21, and a telescopic rod 23 is slidably arranged on the inner side thereof, and a drill bit 24 is detachably connected to the end of the telescopic rod 23. Through the first arc-shaped slide rail 22, the second arc-shaped slide rail 23 and the telescopic rod 23, the drill bit 24 can be driven to move around the sawbone 1, so as to realize drilling of the sawbone 1 from different angles.

[0039] Among them, Figure 6 As shown, an actively rotatable mounting seat 26 is provided at the end of the telescopic rod 23. A mounting groove is provided at the center of the mounting seat 26, and slots penetrating the mounting seat 26 are provided on both sides of the mounting groove, and a magnetic attraction portion is provided at the bottom of the mounting groove. A mounting head 25 adapted to the mounting groove is provided at the end of the drill bit 24, and limit blocks adapted to the slots are provided on both sides of the mounting head 25, and a magnetic attraction portion is provided at the end of the mounting head 25. The drill bit 24 is positioned by the cooperation of the mounting head 25 and the mounting groove, and a magnetically detachable connection is achieved by the interaction of the two magnetic attraction portions, so that the drill bit 24 can be replaced to meet different screw drilling requirements.

[0040] S5: Fix the bone plate 2 and the bone plate fixing screws 3 to the sawbone 1 in accordance with the screw implantation holes drilled in step S4. The bone plate 2 is provided with through holes for the screws to pass through, and each through hole is matched with each screw implantation hole, and then each bone plate fixing screw 3 is screwed into each screw implantation hole to realize the assembly of the bone plate 2.

[0041] S6: Using a cutting mechanism to cut a fracture line on the sawbone 1. Figure 4 and Figure 5As shown, the cutting mechanism includes two fixed sliding rods 31, on which a base 32 is slidably arranged, and the base 32 is slidable by a driving mechanism. A slide groove is provided in the base 32, and a cutter 33 and a cam 34 are arranged in the slide groove. Among them, the cutter 33 is a rectangular structure, a cutting sawtooth is provided at the first end, and the second end is slidably connected in the slide groove. There are two cams 34, which are respectively arranged on the upper and lower sides of the cutter 33, and abut against the edge of the cutter 33, and can drive the cutter 33 to slide up and down in the slide groove. The two cams 32 abut against the two sides of the cutter 33 with a relatively convex side and a relatively non-convex side, respectively, and can drive the cutter 33 to move up and down, so that the cutting sawtooth at the end of the cutter 33 acts on the sawbone bone 1 to achieve cutting. Before cutting, the three-dimensional model of the sawbone bone 1 is cut in the three-dimensional software to form a fracture simulation, and then the position information of the three-dimensional model cut is fed back to the control mechanism, and the control mechanism controls the cutting mechanism to cut the sawbone bone 1 in real object to ensure that the real object has the same structure as the three-dimensional model.

[0042] S7: Fix the remaining plates or screws to sawbone 1 with the holes drilled in step S4. The biomechanical test includes femoral tests with different assembly structures, such as single plate femoral test, single plate plus cancellous bone screw femoral test and double plate femoral test. Among them, the remaining plates include the auxiliary plates fixed on the opposite side of plate 2 in the double plate femoral test; the remaining screws include the auxiliary plate fixing screws and the cancellous bone screws in the single plate plus cancellous bone screw femoral test.

[0043] S8: After the bone implant is implanted, the fixing mechanism drives the sawbone 1 to move so that the inclination angles of the femoral force line in the coronal plane and the sagittal plane meet the test requirements, and the embedding treatment is performed with the dental tray powder, so that the embedding tool 4 is connected to the two ends of the sawbone 1 to complete the assembly. Figure 7 and Figure 8 After the assembly is completed, the assembled structure can be connected to a test device to implement biomechanical testing.

[0044] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A femoral implant biomechanical testing assembly method, characterized in that: The following steps are involved: S1: fix the sawbone using a fixation mechanism (1); S2: 3D scanning points are attached to the apex of the femoral head, the apex of the greater trochanter and the midpoint of the condylar fossa of the sawbone bone (1), and the actual coordinate system of the sawbone bone is obtained through 3D scanning. The actual coordinate system is compared with the coordinate system of the sawbone bone three-dimensional model in the three-dimensional software. If there is a deviation, the position of the sawbone bone (1) is adjusted through a fixing mechanism until the actual coordinate system coincides with the coordinate system of the three-dimensional model; S3: assembling the three-dimensional model of the bone plate and the three-dimensional model of the bone plate fixing screw onto the three-dimensional model of the sawbone bone in the three-dimensional software, and extracting the axis of the assembled three-dimensional model of the screw; S4: driving the drilling mechanism to drill the sawbone according to the axis in step S3; S5: Fixing the bone plate (2) and the bone plate fixing screws (3) to the sawbone (1) through the holes drilled in step S4; S6: using a cutting mechanism to cut a fracture line on the sawbone bone (1); S7: Fixing the remaining bone plates or the remaining screws on the sawbone (1) corresponding to the holes drilled in step S4; S8: After the bone implant is implanted, the fixing mechanism drives the sawbone (1) to move so that the inclination angles of the femoral force line in the coronal plane and the sagittal plane meet the test requirements, and the implant is embedded with dental tray powder so that the embedding tool (4) is connected to the two ends of the sawbone (1); The fixing mechanism comprises a fixing ring (11) and a connecting seat (12); the fixing ring (11) is connected to the connecting seat (12) via a connecting rod (13), and an inflatable clamping mechanism is arranged inside the fixing ring (11); the fixing ring (11) can rotate along its axial direction and can also rotate along the axial direction of the connecting rod (13); the fixing ring (11) and the connecting seat (12) can move left and right; The drilling mechanism comprises a first arc-shaped slide rail (21) and a second arc-shaped slide rail (22); the second arc-shaped slide rail (22) is slidably arranged on the inner side surface of the first arc-shaped slide rail (21), and a telescopic rod (23) is slidably arranged on the inner side surface; the end of the telescopic rod (23) is detachably connected to a drill bit (24).

2. A femoral implant biomechanical testing and assembly method according to claim 1, characterized in that: The fixing ring (11) is sleeved at the middle position of the sawbone (1) when fixing the sawbone (1).

3. A femoral implant biomechanical testing and assembly method according to claim 1, characterized in that: The remaining bone plates in step S7 include auxiliary bone plates fixed on the opposite side of the bone plate (2); and the remaining screws include the auxiliary bone plate fixing screws and cancellous bone screws.

4. A femoral implant biomechanical testing and assembly method according to claim 1, characterized in that: The end of the telescopic rod (23) is provided with an actively rotatable mounting seat (26); a mounting groove is provided at the center of the mounting seat (26); slots penetrating the mounting seat (26) are provided on both sides of the mounting groove, and a magnetic attraction portion is provided at the bottom of the mounting groove; a mounting head (25) adapted to the mounting groove is provided at the end of the drill bit (24); limit blocks adapted to the slot are provided on both sides of the mounting head (25), and a magnetic attraction portion is provided at the end of the mounting head (25).

5. A femoral implant biomechanical testing and assembly method according to claim 1, characterized in that: The cutting mechanism comprises two sliding rods (31); a base (32) is slidably arranged on the sliding rods (31); a sliding groove is provided in the base (32); a cutter (33) and a cam (34) are arranged in the sliding groove; the cutter (33) is in a rectangular structure, a first end is provided with cutting teeth, and a second end is slidably connected in the sliding groove; there are two cams (34), which are respectively arranged on the upper and lower sides of the cutter (33) and abut against the edge of the cutter (33) to drive the cutter (33) to slide up and down in the sliding groove.

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