A femoral bone cutting tool in total knee arthroplasty

Abstract

The present application relates to the technical field of bone cutting tools, and discloses a femur bone cutting tool in total knee arthroplasty, which comprises a fixing part, the fixing part comprises a fixing frame, the outer surface of the fixing frame is fixedly connected with a fixing nail sleeve, and the upper surface of the fixing frame is provided with a mounting groove; the locating part comprises a supporting frame, the bottom end of the supporting frame is fixedly connected with a mounting column which is in close contact with the inner wall surface of the mounting groove, and the outer side of the supporting frame is provided with an execution frame. The femur bone cutting tool in total knee arthroplasty can effectively solve the problem that the tool instruments used in femur joint bone cutting surgery in the prior art are composed of multiple independent parts, the measurement reference and the positioning reference of each tool are independent of each other, the reference transmission completely depends on manual connection in the tool dismounting and replacing process, the reference deviation is further aggravated, and thus the reference transmission is broken, and the surgery precision and efficiency are low.

Description

Technical Field

[0001] This invention relates to the field of osteotomy tools, specifically to a femoral osteotomy tool used in total knee arthroplasty. Background Technology

[0002] Total knee replacement surgery is a very effective treatment for knee-related diseases. It can relieve pain, restore the function of the knee joint, improve the condition of the knee joint, and enhance the patient's quality of life. Total knee replacement surgery mainly involves removing the distal femur, anterior condyle, posterior condyle, superior slope, inferior slope, and tibial plateau of the patient's knee joint, and then replacing them with corresponding femoral and tibial prostheses to replace the patient's original bony features and restore the patient's mobility.

[0003] In the existing technology, the tools and instruments used in femoral osteotomy are composed of multiple independent parts, and the measurement and positioning references of each tool are independent of each other. During the tool replacement process, the reference transfer relies entirely on manual connection, which further aggravates the reference deviation, resulting in reference transfer failure and low surgical accuracy and efficiency. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention provides a femoral osteotomy tool for total knee arthroplasty. This tool effectively solves the problem that existing femoral osteotomy tools are composed of multiple independent components, and the measurement and positioning references of each tool are independent of each other. During tool replacement, the reference transfer relies entirely on manual connection, which further aggravates reference deviation, leading to reference transfer failure and low surgical accuracy and efficiency.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a femoral osteotomy tool for total knee arthroplasty, comprising:

[0007] The fixing part includes a fixing frame, the outer surface of which is fixedly connected with a fixing nail sleeve, and the upper surface of the fixing frame is provided with an installation groove;

[0008] The positioning part includes a support frame, a mounting column that fits against the inner wall surface of the mounting groove is fixedly connected to the bottom end of the support frame, an execution frame is provided on the outer side of the support frame, an adjustment component for adjusting the angle of the execution frame is provided on the outer surface of the support frame, and a U-shaped rod is fixedly connected to the upper surface of the execution frame.

[0009] The connecting part includes a slider that is slidably connected to the outer surface of the U-shaped rod, a connecting rod that is slidably connected inside the slider, an osteotomy plate that is sleeved on the outer surface of the connecting rod, and a connecting member for fixing the position of the osteotomy plate that is provided in the groove provided inside the connecting rod.

[0010] The distance measuring part includes an adjusting block, which is sleeved on the outer surface of the connecting rod away from the osteotomy plate, and an arc-shaped frame is fixedly connected to the outer side of the adjusting block.

[0011] The osteotomy plate has an osteotomy groove, and two oblique top holes are also provided on both sides of the osteotomy plate for fixing the osteotomy plate.

[0012] Furthermore, the adjusting component includes a fixing rod, which is fixedly connected to the outer surface of the support frame near the actuator. A worm gear is rotatably connected inside the support frame. A ball groove is formed on the outer surface of the actuator near the support frame. The outer ends of the fixing rod and the worm gear are provided with universal balls that are rolled and connected to the inner wall of the ball groove.

[0013] Furthermore, there are three ball grooves arranged in an isosceles right triangle, and a pointer is fixedly connected to the upper surface of the fixing frame, with the pointer centrally located in the middle of the fixing frame.

[0014] Furthermore, a sleeve fitted on the outer surface of the worm gear is fixedly connected to the side of the support frame away from the actuator. The outer surface of the sleeve is provided with a scale needle. The end of the worm gear away from the universal ball passes through the sleeve and is fixedly connected to a knob.

[0015] Furthermore, the connecting component includes a reciprocating rod that is slidably connected to the inner wall surface of the slide groove. A connecting rod is rotatably connected to the middle of the reciprocating rod. A through groove communicating with the inside of the slide groove is opened on the outer surface of the connecting rod. A positioning post that slides against the inner wall of the through groove is rotatably connected to the outer end of the connecting rod. The end face of the positioning post is designed with an arc surface. A spring connected to the end face of the reciprocating rod is provided inside the slide groove. A button is fixedly connected to the end of the reciprocating rod away from the spring.

[0016] Furthermore, the adjusting block is slidably connected to a connecting frame through a cavity formed inside it. The bottom of the inner wall of the cavity is provided with a spring piece connected to the lower surface of the connecting frame. The upper surface of the connecting frame is fixedly connected with a pressing handle extending to the upper surface of the adjusting block. The bottom of the inner wall of the connecting frame is fixedly connected with teeth. The lower surface of the connecting rod is provided with a tooth groove that meshes with the outer surface of the teeth.

[0017] Furthermore, a bone measuring plate is rotatably connected to the side of the arc-shaped frame near the osteotomy plate via a rotating shaft. Two bone measuring plates are provided, and the two bone measuring plates are symmetrically distributed around the adjustment block. The bone measuring plates are slidably connected to a bone measuring rod via a slide rail on their outer surface. A pressure plate is fixedly connected to the side of the bone measuring rod away from the arc-shaped frame.

[0018] Furthermore, a fixing block is fixedly connected to the outer surface of the bone measuring plate, and a connecting block is fixedly connected to the outer surface of the bone measuring slide rod. A compression spring connected to the outer surface of the fixing block is provided on the side of the connecting block away from the pressure plate.

[0019] The technical solution provided by this invention has the following advantages compared with the prior art:

[0020] This invention comprises a fixation unit, a positioning unit, a connecting unit, and a distance measuring unit. Compared to existing technologies where multiple instruments are used independently and reference points are fragmented, this invention integrates the fixation, positioning, connecting, and distance measuring units into an organic whole through modular integration and reference point linkage design. The fixation unit uses the Whiteside line and the medullary canal opening point as references, and uses fixation pins with a triangular fixation structure to establish a stable origin, avoiding reference point ambiguity. The fixation unit is precisely connected to the positioning unit through mounting posts and pressure fixation design. At the same time, the orthogonal triangular adjustment structure allows for independent angle control, eliminating dimensional interference from other angles and ensuring accuracy. The connecting unit enables flexible multi-dimensional adjustment and quick locking, connecting with the osteotomy plate and adjustment block to achieve uninterrupted reference point transfer. The compression springs on both sides of the distance measuring unit can adapt to uneven femoral wear, ensuring precise correspondence between distance measurement and osteotomy amount. The reference points of the four components are consistent throughout the entire process, which can significantly reduce errors and operation time. This avoids the situation in existing technologies where the measurement and positioning reference points of each tool are independent, and the reference point transfer during tool replacement relies entirely on manual connection, resulting in reference point transmission breakage and low surgical accuracy and efficiency. Meanwhile, the three-point ball-groove structure distributed in an isosceles triangle forms an orthogonal triangular adjustment system. The tilt-anterior angle adjustment axis is completely orthogonal to the inward and outward flex angle adjustment axis, which solves the technical problem of mutual interference of angles during adjustment in traditional tools. It can flexibly adjust the spatial angle of the actuator and is suitable for different femoral anatomy structures of different patients. The worm gear achieves micro-displacement through precision helical transmission, with high adjustment accuracy. The three points a, b, and c adopt a working mode of one fixed, one adjusted, and one locked, ensuring that the non-adjusted dimension forms a rigid lock, which can avoid the cumulative error caused by multi-degree-of-freedom movement. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0022] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the installation structure according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic cross-sectional view of the connecting rod according to an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the separate structure of the fixing part, positioning part, connecting part and ranging part according to an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the separation structure of the positioning part in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the distribution and structure of the ball grooves in an embodiment of the present invention;

[0028] Figure 7 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of part A in the middle;

[0029] Figure 8 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of section B in the middle;

[0030] Figure 9 This is a schematic diagram of the separated structure of the connecting rod, adjusting block, and connecting frame according to an embodiment of the present invention;

[0031] Figure 10 This is a schematic diagram of the separation structure of the ranging section in an embodiment of the present invention;

[0032] Figure 11 This is a schematic diagram of the installation structure of the fixation part and the femur according to an embodiment of the present invention;

[0033] Figure 12 This is a schematic diagram of the installation structure of the osteotomy plate and the femur in an embodiment of the present invention.

[0034] The labels in the diagram represent: 1. Fixing part; 11. Fixing frame; 12. Fixing nail sleeve; 13. Mounting groove; 14. Pointer; 2. Positioning part; 21. Support frame; 22. Mounting column; 23. Actuating frame; 231. Ball groove; 24. Adjusting component; 241. Fixing rod; 242. Worm gear; 243. Universal ball; 25. U-shaped rod; 26. Sleeve; 3. Connecting part; 31. Slider; 32. Connecting rod; 321. Slide groove; 322. Tooth groove; 33. Osteotomy plate; 34. Connector; 341. Reciprocating rod; 342. Connecting rod; 343. Positioning post; 344. Spring; 4. Measuring part; 41. Adjusting block; 411. Connecting frame; 412. Spring; 413. Pressing handle; 414. Tooth; 42. Arc frame; 43. Bone measuring plate; 431. Fixing block; 44. Bone measuring slide rod; 441. Connecting block; 442. Compression spring; 45. Pressure plate. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] The present invention will be further described below with reference to embodiments. Example

[0037] Please see Figures 1-12 This invention provides a technical solution: a femoral osteotomy tool for total knee arthroplasty, comprising:

[0038] The fixing part 1 includes a fixing frame 11, and a fixing nail sleeve 12 is fixedly connected to the outer surface of the fixing frame 11. The upper surface of the fixing frame 11 is provided with an installation groove 13.

[0039] Positioning part 2 includes a support frame 21. The bottom end of the support frame 21 is fixedly connected to a mounting column 22 that fits against the inner wall surface of the mounting groove 13. An execution frame 23 is provided on the outside of the support frame 21. An adjustment member 24 for adjusting the angle of the execution frame 23 is provided on the outer surface of the support frame 21. A U-shaped rod 25 is fixedly connected to the upper surface of the execution frame 23.

[0040] The connecting part 3 includes a slider 31 that is slidably connected to the outer surface of the U-shaped rod 25. A connecting rod 32 is slidably connected inside the slider 31. An osteotomy plate 33 is sleeved on the outer surface of the connecting rod 32. A connecting member 34 for fixing the position of the osteotomy plate 33 is provided on the connecting rod 32 through a groove 321 provided inside it.

[0041] The distance measuring part 4 includes an adjusting block 41, which is sleeved on the outer surface of the connecting rod 32 away from the osteotomy plate 33. An arc-shaped frame 42 is fixedly connected to the outer side of the adjusting block 41.

[0042] The osteotomy plate 33 has an osteotomy groove, and two oblique top holes are also provided on both sides of the osteotomy plate 33 for fixing the osteotomy plate 33.

[0043] The adjusting component 24 includes a fixing rod 241, which is fixedly connected to the outer surface of the support frame 21 near the actuator 23. A worm gear 242 is rotatably connected inside the support frame 21. A ball groove 231 is provided on the outer surface of the actuator 23 near the support frame 21. The outer ends of the fixing rod 241 and the worm gear 242 are provided with universal balls 243 that are rolled and connected to the inner wall of the ball groove 231. A visualization laser line is installed on the outer surface of the actuator 23 for calibrating the femoral varus / valgus angle and anteversion / posterior tilt angle.

[0044] There are three ball grooves 231, which are arranged in an isosceles right triangle. A pointer 14 is fixedly connected to the upper surface of the fixing bracket 11.

[0045] The support frame 21 is fixedly connected to a sleeve 26 on the outer surface of the worm gear 242 on the side away from the actuator 23. The outer surface of the sleeve 26 is provided with a scale needle. The end of the worm gear 242 away from the universal ball 243 passes through the sleeve 26 and is fixedly connected to a knob.

[0046] The connector 34 includes a reciprocating rod 341 that is slidably connected to the inner wall surface of the slide groove 321. A connecting rod 342 is rotatably connected to the middle of the reciprocating rod 341. A through groove communicating with the inside of the slide groove 321 is opened on the outer surface of the connecting rod 342. A positioning post 343 that slides against the inner wall of the through groove is rotatably connected to the outer end of the connecting rod 342. The end face of the positioning post 343 is designed with an arc surface. A spring 344 connected to the end face of the reciprocating rod 341 is provided inside the slide groove 321. A button is fixedly connected to the end of the reciprocating rod 341 away from the spring 344.

[0047] The adjusting block 41 is slidably connected to the connecting frame 411 through a cavity formed inside it. The bottom of the inner wall of the cavity is provided with a spring piece 412 that is connected to the lower surface of the connecting frame 411. The upper surface of the connecting frame 411 is fixedly connected with a pressing handle 413 that extends to the upper surface of the adjusting block 41. The bottom of the inner wall of the connecting frame 411 is fixedly connected with a tooth 414. The lower surface of the connecting rod 32 is provided with a tooth groove 322 that meshes with the outer surface of the tooth 414.

[0048] The side of the arc frame 42 closest to the osteotomy plate 33 is rotatably connected to the bone measuring plate 43 via a rotating shaft. There are two bone measuring plates 43, which are symmetrically distributed around the adjusting block 41. The bone measuring plate 43 is slidably connected to the bone measuring slide rod 44 via a slide rail on its outer surface. The side of the bone measuring slide rod 44 away from the arc frame 42 is fixedly connected to the pressure plate 45.

[0049] A fixing block 431 is fixedly connected to the outer surface of the bone measuring plate 43, and a connecting block 441 is fixedly connected to the outer surface of the bone measuring slide rod 44. A compression spring 442 connected to the outer surface of the fixing block 431 is provided on the side of the connecting block 441 away from the pressure plate 45.

[0050] The fixing part 1 is mainly used to install the positioning part 2 to collect data on the distal femoral angle of the patient. The fixing frame 11 has a mounting groove 13 for installing the positioning part 2. The fixing frame 11 is also provided with a pressure fixing structure for fixing the positioning part 2 after it is installed. The pressure is applied to the positioning part 2 to achieve the purpose of fixing the support frame 21. In addition to the fixing screw sleeves 12 fixedly connected on both sides, the fixing frame 11 also has a central screw hole in the middle. The central screw hole and the pointer 14 are both located in the middle of the fixing frame 11.

[0051] During the femoral osteotomy procedure in total knee arthroplasty, the fixation frame 11 is first fixed in the preset position at the distal end of the patient's femur. During installation, the pointer 14 is pointed to the whiteside line (the whiteside line is a bony ridge extending in the anterior-posterior direction within the trochlear groove of the femur, which is the core anatomical benchmark for femoral osteotomy positioning in total knee arthroplasty, and is an industry term). The central screw hole on the fixation frame 11 is pointed to the medullary canal opening point on the whiteside line (the medullary canal opening point is a distance above the posterior cruciate ligament). Then, the fixation screws are used to fix the fixation frame 11 through two fixation screw sleeves 12 to ensure that the fixation frame 11 is stable and reliable.

[0052] Subsequently, the mounting post 22 on the lower surface of the support frame 21 in the positioning part 2 is inserted into the mounting groove 13 of the fixing frame 11, completing the initial connection between the support frame 21 and the fixing frame 11. The support frame 21 is connected to the actuator 23 through the adjusting member 24 and is synchronously installed on the outer surface of the fixing part 1.

[0053] Based on the anatomical structure of the patient's femur and the surgical osteotomy requirements, the angle of the actuator 23 is adjusted using the adjusting component 24. During the adjustment process, the adjustment angle of the actuator 23 is observed and determined by the scale pin on the outer surface of the sleeve 26 in conjunction with the pointer 14 on the fixation frame 11, ensuring precise angle adjustment.

[0054] The outer surface of the actuator 23 has three ball grooves 231. The connecting line of the three ball grooves 231 is distributed in an isosceles right triangle. In the isosceles right triangle formed by the three ball grooves 231, one right-angled side is horizontal and the other right-angled side is vertical. Two of the ball grooves 231 are rotatably connected to the surface of the universal ball 243 at the outer end of the worm gear 242, and the other ball groove 231 is rotatably connected to the surface of the universal ball 243 at the outer end of the fixed rod 241. The ball groove 231 corresponding to the outer end of the fixed rod 241 is the right-angle vertex of the connecting line of the isosceles right triangle (marked as point a). In addition, the ball groove 231 corresponding to the outer end of the worm gear 242 is the intersection of the vertical right-angled side and the hypotenuse of the isosceles right triangle (marked as point b), and the ball groove 231 corresponding to the outer end of the other worm gear 242 is the intersection of the horizontal right-angled side and the hypotenuse of the isosceles right triangle (marked as point c). Among them, the three ball grooves 231 have different functions:

[0055] Point a, ball groove 231: Located at the intersection of the two right-angled sides of an isosceles right triangle, this ball groove 231 is rotatably connected to the universal ball 243 at the outer end of the fixed rod 241, serving as the reference fulcrum for the angle adjustment of the entire actuator 23. Point a, as the fulcrum of the right-angled vertex fixed rod 241, has its universal ball 243 providing only rotational support within the ball groove 231, without generating any axial displacement along the sleeve 26. This ensures that the rotation of the actuator 23 is always based on point a, further limiting the dimension of motion and preventing lateral offset.

[0056] Point b, ball groove 231: is the intersection of the right-angled side and the hypotenuse of an isosceles right triangle in its vertical state. A universal ball 243 at the outer end of one of the worm gears 242 is rotatably connected inside the ball groove 231, which is the adjustment fulcrum for the front and rear tilt angle of the actuator 23.

[0057] c-point ball groove 231: is the intersection of the right-angled side and the hypotenuse of the horizontal state of the isosceles right triangle. The ball groove 231 is rotatably connected to the universal ball 243 at the outer end of another worm gear 242, which is the adjustment fulcrum for the inner and outer flip angles of the actuator 23.

[0058] According to the preoperatively planned target value for the longitudinal tilt angle, slowly rotate the knob corresponding to the worm gear 242 at point b ball groove 231. Since the worm gear 242 forms a helical drive with the threaded groove inside the support frame 21, rotating the worm gear 242 will cause it to shift axially along the sleeve 26, pushing the universal ball 243 inside the ball groove 231 at point b to move in an arc around point a (the universal ball 243 at the outer end of the fixed rod 241) as the center, thereby causing the actuator 23 to tilt longitudinally around the horizontal axis (the line connecting points a and c). At this time, the fixed rod 241 and worm gear 242 corresponding to points a and c remain fixed.

[0059] When it is necessary to adjust the inward and outward turning angles (lateral rotation angles) of the actuator 23, rotate the worm 242 corresponding to the ball groove 231 at point c. Similarly, the axial displacement of the worm 242 will push the ball groove 231 at point c to perform a lateral arc motion around point a, causing the actuator 23 to rotate laterally around the vertical axis. At this time, the fixed rod 241 and worm 242 corresponding to points a and b remain stationary.

[0060] During the two angle adjustments described above, the fixed rod 241 at point a always serves as the core fixed fulcrum. The cooperation between the universal ball 243 at its outer end and the ball groove 231 provides stable support for the rotation of the actuator 23, preventing wobbling during the adjustment process. At the same time, the worm gear 242 on the non-adjustment side is locked to ensure that it does not participate in the movement, preventing interference between multi-dimensional adjustments.

[0061] The fixed rod 241 fulcrum (right-angle vertex a), the tilt angle adjusting worm 242 fulcrum (vertical right-angle end point b), and the inward / outward angle adjusting worm 242 fulcrum (horizontal right-angle end point c) form an orthogonal triangular structure. Its core advantage lies in the fact that the adjustment axes of the tilt angle and the inward / outward angle are completely perpendicular and independent: the tilt angle adjustment axis is the line connecting points a and c (horizontal right-angle side), extending horizontally along the coronal plane of the human body. During adjustment, the actuator 23 rotates around this axis in the sagittal plane, producing only a tilt angle and no left or right offset; the inward / outward angle adjustment axis is the vertical axis passing through point a (extending vertically along the human body). During adjustment, the actuator 23 rotates around this axis in the coronal plane (producing only a left or right offset and no tilt angle).

[0062] Because the two adjustment axes are orthogonal at 90 degrees and each corresponds to an independent worm gear 242 (worm gear 242 at point b is responsible for tilt and flexion, and worm gear 242 at point c is responsible for valgus and inversion), when adjusting one dimension, the movement trajectory only unfolds along the corresponding plane and will not cross the adjustment plane of the other dimension. This structurally avoids interference caused by adjusting the tilt angle affecting the valgus and inversion angles, or vice versa. The three points of the adjustment component 24 adopt a configuration of one fixed, one adjusting, and one locked, ensuring both the accuracy of angle adjustment and the overall structural stability of the tool, fully meeting the stringent requirements for femoral osteotomy tools in total knee arthroplasty.

[0063] The process of measuring the distance of the femur and installing the osteotomy plate 33:

[0064] After angle adjustment, slide the slider 31 on the U-shaped rod 25 to adjust the height of the connecting part 3. The side of the adjusting block 41 away from the bone measuring plate 43 is the measuring surface, and the upper surface of the connecting rod 32 has corresponding scale lines. Move the measuring part 4 according to the required osteotomy position so that the measuring surface of the adjusting block 41 is aligned with the required scale line on the upper surface of the connecting rod 32. Press the pressing handle 413 protruding above the adjusting block 41, compress the spring piece 412 through the connecting frame 411, so that the teeth 414 at the bottom of the connecting frame 411 disengage from the tooth groove 322 on the lower surface of the connecting rod 32, and slide the adjusting block 41 on the connecting rod 32 until the measuring surface of the adjusting block 41 is aligned with the required scale line on the upper surface of the connecting rod 32. Release the pressing handle 413, and under the elastic force of the spring piece 412, the connecting frame 411 resets, the teeth 414 re-engages with the tooth groove 322, and the position of the adjusting block 41 is fixed.

[0065] The upper surface of the connecting rod 32 has corresponding scale lines representing the initial osteotomy amount. For example, when the measuring surface of the adjusting block 41 is aligned with the 9mm scale line, it indicates that the initial osteotomy amount is 9mm. 9mm refers to the vertical distance D between the outer surface of the pressure plate 45 away from the bone measuring slide rod 44 and the bottom surface of the osteotomy groove of the osteotomy plate 33 in the retracted state of the bone measuring plate 43 and the bone measuring slide rod 44 on one side of the measuring part 4 (the adjacent surfaces of the connecting block 441 and the fixing block 431 are in contact). The bone measuring plates 43 on both sides are connected to the arc frame 42 through two rotating shafts. When the distal femur of the patient is small, the two bone measuring plates 43 can rotate inward to reduce the distance, so that they can touch the distal femur surface and thus determine the osteotomy amount.

[0066] Pressing the button on the outer end of the connecting rod 32 pushes the reciprocating rod 341 to compress the spring 344 inside the slide groove 321. The reciprocating rod 341 drives the connecting rod 342 to rotate, and the connecting rod 342 pulls the positioning pin 343 back into the through groove. At this time, the position of the sliding osteotomy plate 33 on the connecting rod 32 is adjusted so that the osteotomy plate 33 is placed in the corresponding position on the outer surface of the connecting rod 32. Releasing the button causes the reciprocating rod 341 to return to its original position under the elastic force of the spring 344, driving the connecting rod 342 to rotate in the opposite direction. The connecting rod 342 pushes the positioning pin 343 out of the through groove and inserts it into the positioning hole of the osteotomy plate 33. The osteotomy plate 33 is then fixed under the action of the connecting piece 34.

[0067] At this point, the adjusting block 41, connecting rod 32, and osteotomy plate 33 form a whole, moving simultaneously towards the femur. One end of the compression spring 442 is connected to the bone measuring plate 43 via the fixing block 431, and the other end is connected to the bone measuring slide rod 44 via the connecting block 441. Initially, the pressure plate 45 in the measuring part 4 is not in contact with the outside, and the connecting block 441 is not in contact with the outer surface of the fixing block 431; the compression spring 442 is in its maximum extended state. As the adjusting block 41 moves towards the femur, the arc frame 42, bone measuring plate 43, bone measuring slide rod 44, and pressure plate 45 move together until one of the pressure plates 45 contacts the distal end of the femur.

[0068] Because knee joint diseases such as osteoarthritis and rheumatoid arthritis often lead to uneven wear of the distal femoral condyles, or uneven bone surfaces caused by trauma, when the measuring part 4 is translated, an asymmetrical fitting phenomenon will inevitably occur where the pressure plate 45 on one side contacts the bone surface first.

[0069] While the pressure plate 45 on one side contacts and compresses the compression spring 442, the pressure plate 45 on the non-contact side remains uncontacted due to severe bone surface wear or indentation. Therefore, the sliding rod 44 on that side remains in its initial position, the distance between the connecting block 441 and the fixing block 431 remains unchanged, and the compression spring 442 is always in its maximum extended state. At this time, the continuous translation of the measuring part 4 is transformed into further compression of the single-sided compression spring 442 and continued approach of the non-contact side: the compression of the compression spring 442 on the contact side increases synchronously with the moving distance, and the elastic force gradually increases to maintain the tight fit between the pressure plate 45 and the bone surface; the pressure plate 45 on the non-contact side continues to move towards the bone surface with the arc frame 42 until its end face contacts the lateral condyle bone surface, achieving complete fit between the two pressure plates 45.

[0070] During this process, when the single-sided pressure plate 45 first contacts the femur (the side with less wear), the compression spring 442, through the connecting block 441, receives the thrust of the measuring slide rod 44, replacing rigid clamping with elastic compression. This ensures that the pressure plate 45 fits tightly against the bone surface while avoiding excessive force on the bone surface due to the continuous translation of the measuring part 4, which could cause damage to the bone cortex or the formation of bone fragments. This is suitable for scenarios involving uneven bone surfaces caused by osteoarthritis or trauma. The continuous compression of the compression spring 442 generates a stable pre-tension force for contact, rather than the instantaneous force of rigid contact, ensuring that the pressure plate 45 fits tightly against the bone surface and avoiding false measurement errors caused by surface contact without reaching the true reference plane due to osteophytes or cartilage residue. During this process, the deformation difference of the compression spring 442 automatically adapts to the uneven wear of the distal femur, avoiding measurement deviations caused by uneven bone surfaces.

[0071] The compression springs 442 on both sides are connected to their respective components via independent fixing blocks 431 and connecting blocks 441, forming a left-right separation state. The compression spring 442 on the side that contacts first is continuously compressed to buffer the translational force, while the compression spring 442 on the side that does not contact (the side with more wear or concavity) remains in its maximum extended state, continuing to approach the bone surface with the arc frame 42 until the pressure plate 45 contacts it. This design of buffering on one side and following on the other can solve the benchmark distortion problem caused by the suspension on one side when the traditional rigid measurement structure is used in cases of uneven wear on both sides of the femur, ensuring that the pressure plates 45 on both sides eventually fit against the bone surface.

[0072] After both sides of the pressure plate 45 are in contact with the distal end of the femur, they continue to move until the connecting block 441 of one side (the side that contacts the femur first) comes into contact with the outer surface of the fixing block 431. At this time, the vertical distance between the outer surface of the pressure plate 45 away from the bone measuring slide rod 44 and the bottom surface of the osteotomy groove of the osteotomy plate 33 is the same as the data after the measuring surface of the adjusting block 41 is aligned with the scale line. The measuring part 4 reaches the preset osteotomy position.

[0073] Since the adjusting block 41, connecting rod 32 and osteotomy plate 33 form a whole, the osteotomy plate 33 moves synchronously during the movement of the measuring part 4. At this time, the position of the osteotomy plate 33 is the position of the required osteotomy amount. Two threaded nails are used to fix the osteotomy plate 33 through the two nail holes on the osteotomy plate 33. Finally, another threaded nail is driven through the oblique top hole on the osteotomy plate 33 to completely fix the osteotomy plate 33.

[0074] After the osteotomy plate 33 is installed, press the button at the rear end of the connecting rod 32. Under the action of the button, the reciprocating rod 341 slides towards the spring 344 inside the connecting rod 32. Under the compression of the reciprocating rod 341, the spring 344 is compressed. Simultaneously, the reciprocating rod 341 drives the connecting rod 342 to rotate, gradually changing the connecting rod 342 from a vertical state to an inclined state. The connecting rod 342 pulls the two positioning pins 343 back into the through groove, and the outer surface of the positioning pins 343 disengages from the positioning holes inside the osteotomy plate 33. At this point, pull the connecting rod 32 outwards. When the connecting rod 32 is completely disengaged from the osteotomy plate 33, the button can be released. The positioning part 2 can then be removed from the fixing part 1. Finally, remove the three threaded pins on the fixing part 1 and remove the fixing part 1. After removing the fixing part 1, only the osteotomy plate 33 remains at the distal femur, and the entire distal femur is completely exposed. At this point, the distal femur osteotomy can be performed using a oscillating saw with the osteotomy groove.

[0075] In summary, this femoral osteotomy tool has the following advantages:

[0076] Advantage 1: Compared to existing technologies that use multiple instruments independently and suffer from fragmented references, this invention integrates the fixation unit 1, positioning unit 2, connecting unit 3, and distance measuring unit 4 into a unified whole through modular integration and reference linkage design. The fixation unit 1 uses the Whiteside line and the medullary canal opening point as dual anatomical references, employing a triangular fixation structure with fixation pins to establish a stable origin, avoiding reference ambiguity. The fixation unit 1 is precisely connected to the positioning unit 2 via mounting posts 22 and a pressure fixation design. Simultaneously, the orthogonal triangular adjustment structure allows for independent angle control, eliminating dimensional interference from other angles and ensuring accuracy. The connecting unit 3 enables flexible multi-dimensional adjustment and rapid locking, transmitting references uninterruptedly. The compression springs 442 on both sides of the distance measuring unit 4 adapt to uneven femoral wear, ensuring precise correspondence between distance measurement and osteotomy amount. The references of the four components are consistent throughout the entire process, significantly reducing errors and operation time.

[0077] Advantage 2: The adjusting component 24 of the positioning part 2 is connected to the worm gear 242 and the universal ball 243 and the ball groove 231 by rolling. Through the axial displacement of the worm gear 242, the actuator 23 is driven to rotate around the center of the universal ball 243 at the outer end of the fixed rod 241. The spatial angle of the actuator 23 can be flexibly adjusted, which can be adapted to the anatomical structure of the femur of different patients.

[0078] Thirdly, traditional osteotomy tools often employ non-orthogonal structures for angle adjustment. Adjusting one dimension can easily cause changes in the angle of another dimension, requiring repeated fine-tuning, which not only prolongs the operation time but also makes it difficult to guarantee adjustment accuracy. In this invention, the positioning part 2 adopts a three-point ball groove 231 structure with an isosceles triangle distribution (point a is the reference fulcrum, point b is the anteroposterior tilt adjustment point, and point c is the inversion / exversion adjustment point), constructing an orthogonal triangular adjustment system. The anteroposterior tilt adjustment axis (ac horizontal axis) and the inversion / exversion adjustment axis (vertical axis passing through point a) are completely orthogonal, which solves the technical problem of mutual angle interference during adjustment of traditional tools. It allows for flexible adjustment of the spatial angle of the execution frame 23, suitable for the anatomical structure of the femur in different patients. The worm gear 242 achieves micro-displacement through precision helical transmission, resulting in high adjustment accuracy. The three points a, b, and c adopt a working mode of one fixed, one adjusted, and one locked, ensuring that the non-adjusted dimension forms a rigid lock and avoiding cumulative errors caused by multi-degree-of-freedom movement.

[0079] Fourthly, the slider 31 of the connecting part 3 can slide vertically on the outer surface of the U-shaped rod 25, and the connecting rod 32 can slide horizontally within the slider 31, enabling flexible adjustment of the osteotomy plate 33 in both horizontal and vertical directions, thus expanding the adjustment range of the osteotomy position. There are significant individual differences in the anatomical dimensions of the distal femur among different patients. The distance between the medial and lateral condyles of the femur is longer in adults, shorter in children or short patients, and even longer in tall patients. Existing osteotomy tools often have fixed-size support structures, which cannot dynamically adjust the support range according to the patient's anatomical dimensions. However, in the measuring part 4 of this invention, the bone measuring plate 43 and the arc-shaped frame 42 are connected by a rotating shaft. When the distal femur of a patient is small, the two bone measuring plates 43 can rotate inward to reduce the distance, thus allowing them to contact the distal femur surface and determine the amount of osteotomy.

[0080] Advantage 5: Traditional osteotomy tools often employ rigid measuring structures. However, many surgeons experience asymmetrical wear on the distal femur due to arthritis or trauma. Traditional rigid measuring tools struggle to simultaneously conform to both bone surfaces, leading to measurement errors and potential damage or distortion due to forced compression. In this invention, two versions of the bone measuring plate 43, fixing block 431, measuring slide rod 44, connecting block 441, compression spring 442, and pressure plate 45 are symmetrically distributed around the adjusting block 41. Both sides operate independently. When one side contacts the bone surface first, the compression spring 442 can buffer the translational force, preventing injury. The side that hasn't contacted the bone surface continues to approach until contact. This process automatically compensates for measurement errors caused by uneven bone surface wear, ultimately ensuring that both pressure plates 45 are synchronously aligned with the bone surface reference. The corresponding scale line on the connecting rod 32 serves as a precise reference for the osteotomy amount, ensuring center-of-gravity balance and accurate measurement.

[0081] Advantage Six: The connector 34 employs a spring 344 driving the positioning post 343, enabling rapid fixing and unlocking of the osteotomy plate 33. This provides convenient operation and stable, reliable fixation, preventing displacement of the osteotomy plate 33 during measurement and ensuring accuracy. Pressing the handle 413 causes the connecting frame 411 to press the spring 412, disengaging the teeth 414 from the lower surface groove 322 of the connecting rod 32. This also allows for quick disassembly of the connecting rod 32 and the adjusting block 41, achieving tool-free rapid disassembly, reducing the frequency of surgical instrument changes, and shortening surgical time. Simultaneously, the gentle, elastic unlocking and separation method reduces the knocking and twisting actions required for traditional tool disassembly, minimizing interference with the distal femoral bone surface, reducing bone fragment formation and the risk of cortical bone damage, further enhancing surgical safety and precision.

[0082] Advantage 7: When measuring the osteotomy distance, after both sides of the pressure plate 45 are in contact with the distal femur, they continue to move until the connecting block 441 of one side (the side that contacts the femur first) contacts the outer surface of the fixing block 431. At this time, the vertical distance between the outer surface of the pressure plate 45 away from the bone measuring slide rod 44 and the bottom surface of the osteotomy groove of the osteotomy plate 33 is the same as the data after the measuring surface of the adjusting block 41 is aligned with the scale line. The measuring part 4 has reached the preset osteotomy position. The contact between the connecting block 441 and the outer surface of the fixing block 431 ensures that the minimum contraction distance of the bone measuring slide rod 44 and the bone measuring plate 43 is the same as the vertical distance between the outer surface of the pressure plate 45 and the bottom surface of the osteotomy groove of the osteotomy plate 33, thus ensuring the preset scale value of the adjusting block 41 and further guaranteeing the safety and accuracy of the osteotomy distance operation.

[0083] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A femoral osteotomy tool for total knee arthroplasty, characterized in that, include: The fixing part (1) includes a fixing frame (11), and a fixing nail sleeve (12) is fixedly connected to the outer surface of the fixing frame (11). The upper surface of the fixing frame (11) is provided with an installation groove (13). The positioning part (2) includes a support frame (21). The bottom end of the support frame (21) is fixedly connected to a mounting column (22) that fits against the inner wall surface of the mounting groove (13). An execution frame (23) is provided on the outside of the support frame (21). An adjustment member (24) for adjusting the angle of the execution frame (23) is provided on the outer surface of the support frame (21). A U-shaped rod (25) is fixedly connected to the upper surface of the execution frame (23). The connecting part (3) includes a slider (31) slidably connected to the outer surface of the U-shaped rod (25), a connecting rod (32) slidably connected inside the slider (31), an osteotomy plate (33) is sleeved on the outer surface of the connecting rod (32), and a connecting member (34) for fixing the position of the osteotomy plate (33) is provided in the connecting rod (32) through a groove (321) opened inside it. The measuring part (4) includes an adjusting block (41), which is sleeved on the outer surface of the connecting rod (32) away from the osteotomy plate (33). An arc-shaped frame (42) is fixedly connected to the outer side of the adjusting block (41). The adjusting component (24) includes a fixing rod (241), which is fixedly connected to the outer surface of the support frame (21) near the actuator (23). A worm gear (242) is rotatably connected inside the support frame (21). A ball groove (231) is provided on the outer surface of the actuator (23) near the support frame (21). The outer ends of the fixing rod (241) and the worm gear (242) are each provided with a universal ball (243) that is rolled and connected to the inner wall of the ball groove (231). The ball groove (231) is provided in three ways, and the three ball grooves (231) are distributed in an isosceles right triangle. The upper surface of the fixed frame (11) is fixedly connected to the pointer (14). The side of the support frame (21) away from the execution frame (23) is fixedly connected to the sleeve (26) sleeved on the outer surface of the worm (242). The outer surface of the sleeve (26) is provided with a scale needle. The end of the worm (242) away from the universal ball (243) passes through the sleeve (26) and is fixedly connected to the knob.

2. The femoral osteotomy tool for total knee arthroplasty according to claim 1, characterized in that: The connector (34) includes a reciprocating rod (341) that is slidably connected to the inner wall surface of the slide groove (321). A connecting rod (342) is rotatably connected to the middle of the reciprocating rod (341). A through groove communicating with the inside of the slide groove (321) is opened on the outer surface of the connecting rod (321). A positioning post (343) that slides against the inner wall of the through groove is rotatably connected to the outer end of the connecting rod (342). The end face of the positioning post (343) is designed with an arc surface. A spring (344) that is connected to the end face of the reciprocating rod (341) is provided inside the slide groove (321).

3. The femoral osteotomy tool for total knee arthroplasty according to claim 2, characterized in that: The adjusting block (41) is slidably connected to a connecting frame (411) through a cavity opened inside it. A spring piece (412) connected to the lower surface of the connecting frame (411) is provided at the bottom of the inner wall of the cavity. A pressing handle (413) extending to the upper surface of the adjusting block (41) is fixedly connected to the upper surface of the connecting frame (411). A tooth (414) is fixedly connected to the bottom of the inner wall of the connecting frame (411). A tooth groove (322) that meshes with the outer surface of the tooth (414) is opened on the lower surface of the connecting rod (32).

4. The femoral osteotomy tool for total knee arthroplasty according to claim 3, characterized in that: The side of the arc frame (42) near the osteotomy plate (33) is rotatably connected to the bone measuring plate (43) via a rotating shaft. There are two bone measuring plates (43), which are symmetrically distributed around the adjustment block (41). The bone measuring plate (43) is slidably connected to the bone measuring rod (44) via a slide rail on its outer surface. The side of the bone measuring rod (44) away from the arc frame (42) is fixedly connected to the pressure plate (45).

5. The femoral osteotomy tool for total knee arthroplasty according to claim 4, characterized in that: A fixing block (431) is fixedly connected to the outer surface of the bone measuring plate (43), and a connecting block (441) is fixedly connected to the outer surface of the bone measuring slide rod (44). A compression spring (442) connected to the outer surface of the fixing block (431) is provided on the side of the connecting block (441) away from the pressure plate (45).

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