Detachable locking structure of femoral condyle test die and intercondylar test die

Abstract

This invention discloses a detachable locking structure for a femoral condyle trial mold and an intercondylar trial mold, belonging to the field of medical device technology. In this detachable locking structure, the femoral condyle trial mold has an intercondylar groove in the middle, and the intercondylar trial mold is detachably connected within the intercondylar groove. The intercondylar groove has positioning grooves on its left and right front sides, and a cam with positioning holes at its rear. The intercondylar trial mold has a positioning boss at its front end that mates with the positioning grooves, and a retractable positioning post at its rear end that mates with the positioning holes. This invention is mainly used to evaluate the size and dimensions of the osteotomy surface after a four-in-one osteotomy in knee replacement surgery, before the intercondylar section is removed, to ensure its physiological match with the patient's bones, and to measure the size and dimensions of the patient's intercondylar section after osteotomy. It is convenient to install, firmly fixed, easy to disassemble, reusable, safe, reliable, and allows doctors to accurately and quickly select a suitable femoral condyle prosthesis for implantation.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a detachable locking structure for a femoral condyle test mold and an intercondylar test mold. Background Technology

[0002] Knee replacement surgery is a complex procedure requiring numerous surgical instruments, which increases the operation time and has a certain impact on the patient's physical trauma and postoperative recovery. Currently, a fast, precise, safe, reliable, and easy-to-use surgical method is a prerequisite and a routine procedure for surgeons to complete knee replacement surgery. However, the assembly structure and fixation stability of instruments produced by different manufacturers vary, which affects the surgeon's ability to quickly and accurately determine the size of the femoral condyle prosthesis in key surgical steps to select a prosthesis that matches the patient's physiological anatomy, thus prolonging the operation time.

[0003] This instrument is mainly used to help doctors quickly and accurately assemble, fix firmly, and accurately measure the femoral condyle prosthesis to achieve physiological matching with the patient's bones after a four-in-one osteotomy in knee replacement surgery without cutting the intercondylar section. Currently, the corresponding instruments on the market are femoral condyle trial molds and (femoral) intercondylar trial molds. The instruments mainly include the following types: (1) femoral condyle trial mold and intercondylar trial mold with threaded locking method; (2) femoral condyle trial mold and intercondylar trial mold with slot and spring deformation compression locking method; (3) femoral condyle trial mold and intercondylar trial mold with fixed shaft and ball head plunger with damping locking method; (4) femoral condyle trial mold and intercondylar trial mold with integrated design structure. These existing technologies all have inconveniences in use and need to be improved. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a detachable locking structure for the femoral condyle test mold and the intercondylar test mold that is easy to install, firmly fixed, safe and reliable.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A detachable locking structure for a femoral condyle trial mold and an intercondylar trial mold, wherein the femoral condyle trial mold has an intercondylar groove in the middle, and the intercondylar trial mold is detachably connected to the intercondylar groove, wherein:

[0007] The intercondylar groove is provided with positioning grooves on the left and right sides in front, and a cam is provided at the rear of the intercondylar groove, with positioning holes on the cam;

[0008] The front end of the intercondylar test mold is provided with a positioning boss that mates with the positioning groove, and the rear end of the intercondylar test mold is provided with a retractable positioning post that mates with the positioning hole.

[0009] Furthermore, the line connecting the center point of the patellar trochlea of ​​the femoral condyle model and the positioning groove, and the vertical center line of the femoral condyle model when the person is standing, the included angle between the two lines is 60°.

[0010] Furthermore, the distance between the outer edges of the two positioning grooves and the width of the intercondylar mold are both 20mm to 40mm;

[0011] And / or, the width of each positioning groove and positioning boss is 4mm to 10mm;

[0012] And / or, the diameters of the positioning holes and positioning pins are both 2mm to 6mm.

[0013] Furthermore, the inner side of the cam is provided with a guide groove for guiding the positioning pin to slide into the positioning hole.

[0014] Furthermore, the cross-section of the guide groove is an arc with a radius of 1mm to 6mm.

[0015] Furthermore, the intercondylar trial mold is provided with a trolley device, which includes a slide rail extending in the front-rear direction and a slider located in the slide rail. The rear end of the slider is connected to the positioning post, and an elastic element for pushing the slider to extend the positioning post is provided between the front end of the slider and the front side wall of the slide rail.

[0016] Furthermore, the slider is provided with ergonomically designed hand-operated holes.

[0017] Furthermore, the elastic element is a spring, and a spring fixing post is provided on the front side wall of the slide;

[0018] And / or, the slider has a limiting groove extending in the front-to-back direction on its side, and the slide rail has a limiting pin on its side wall, with the end of the limiting pin extending into the limiting groove.

[0019] Furthermore, the front wall of the intercondylar mold is an inclined surface of 40°-50°;

[0020] And / or, the positioning boss has a guide arc on the surface near the front wall of the intercondylar mold.

[0021] Furthermore, both the slide rail and the slider are lower at the rear and higher at both ends;

[0022] And / or, the intercondylar test mold is provided with a pair of sidewalls above the trolley device, and the middle of the pair of sidewalls is provided with an upwardly extending extension.

[0023] The present invention has the following beneficial effects:

[0024] The detachable locking structure of the femoral condyle and intercondylar trial molds of this invention is mainly used to evaluate the size and dimensions of the osteotomy surface after a four-in-one osteotomy in knee replacement surgery, before the intercondylar section is cut, to ensure it matches the patient's skeletal physiology (femoral condyle trial mold 1 is used alone in this case), and after the intercondylar osteotomy, to measure the size and dimensions of the patient's intercondylar section (femoral condyle trial mold 1 and intercondylar trial mold 2 are used together in this case). It is convenient to install, securely fixed, easy to disassemble, reusable, safe, reliable, and allows doctors to accurately and quickly select a suitable femoral condyle prosthesis for implantation. In this invention, the positioning grooves and positioning holes work together, with the two positioning grooves and the positioning holes forming a triangular positioning (see...). Figure 5 The triangular fixing mechanism 16) restricts six degrees of freedom: left and right, front and back, and up and down, which firmly fixes the intercondylar mold and increases the fixation effect of the detachable intercondylar mold. This triangular fixing and positioning principle is safer, more secure, easier to install and assemble, and saves surgical time than the methods used in current technologies. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the detachable locking structure of the femoral condyle test mold and the intercondylar test mold of the present invention;

[0026] Figure 2 for Figure 1 Lateral sectional view of the mid-femoral condyle trial model;

[0027] Figure 3 for Figure 1 Top view of the mid-femoral condyle trial model;

[0028] Figure 4 for Figure 1 A bottom view of the trial model of the middle femoral condyle;

[0029] Figure 5 for Figure 1 Front view of the mid-femoral condyle trial model;

[0030] Figure 6 for Figure 1 Front view of the intercondylar trial model;

[0031] Figure 7 for Figure 1 Side sectional view of the intercondylar trial model;

[0032] Figure 8 for Figure 1 A three-dimensional view of the intercondylar model;

[0033] Figure 9 for Figure 1 Assembly sequence diagram of the mid-femoral condyle trial model and the intercondylar trial model;

[0034] Figure 10 for Figure 1The structural diagrams of the mid-femoral condyle trial model and the intercondylar trial model after assembly, where (a) is a three-dimensional view from one direction and (b) is a three-dimensional view from another direction. Detailed Implementation

[0035] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0036] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0037] The purpose of combining femoral condyle trial molds and intercondylar trial molds is to help surgeons quickly, accurately, and firmly assemble and fix the femoral condyle prosthesis model to match the patient's skeletal physiology after a four-in-one osteotomy in knee replacement surgery, when the intercondylar section has not been removed.

[0038] The existing technology (1) provides a threaded fixation method for the femoral condyle trial mold and the intercondylar trial mold. This threaded fixation method has a good fixation effect during operation and is firmly fixed. However, on the one hand, the operation is extremely inconvenient and the operation is complicated. The doctor needs to manually screw in the screw to achieve the fixation effect. This operation increases the time for instrument assembly and thus increases the operation time. On the other hand, the screw is small and is easy to lose during the handling, disinfection and transportation process. It is also difficult to find. The threads on the small screw are easy to come off and break, which makes it impossible to screw into the femoral condyle trial mold, causing the fixation of the femoral condyle trial mold and the intercondylar trial mold to fail, affecting the operation and increasing the operation time.

[0039] The existing technology, structure (2), is an improvement on structure (1). The femoral condyle mold and the intercondyle mold are locked by a groove and a spring deformation compression locking method. This method is simple to operate, and the installation time of the femoral condyle mold and the intercondyle mold is short. The operation is convenient and the operation time is short. However, the actual clinical application effect is poor because the spring of the spring structure is too small and the strength is not enough. If the spring is thickened, the elasticity will be poor or even non-elastic. After a few uses, the spring is easily damaged and cannot be inserted into the femoral condyle mold, which affects the operation.

[0040] The existing technology (3) structure has two fixed shafts at the upper end of the intercondylar mold, and the femoral condylar mold has a groove and a damped ball plunger device. This has a better fixation effect than the previous two types and solves the problems of thread damage, loss, and shrapnel damage. However, in actual clinical practice, this locking is fixed by the left and right shafts and the upper and lower ball plungers to prevent dislodgement. During the operation, due to the compression between the intercondylar mold and the intercondylar fossa of the human body, after installation, the compression force can easily unlock the intercondylar mold from the femoral condylar mold, which does not achieve the fixation effect and affects the operation.

[0041] The existing technology, type (4), is an integrated design of the intercondylar trial mold on the femoral condylar trial mold, which cannot be disassembled. Although the integrated design is better than the previous types, eliminating the need for assembly and improving safety, it is not suitable for clinical operation. The integrated design affects the correct placement of the femoral prosthesis due to the intercondylar position (i.e., the location of the intercondylar trial mold). After the four-in-one osteotomy, the intercondylar position obstructs the measurement of the human femur size in advance. The intercondylar position must be removed before the human femoral condyle size can be matched with the femoral condyle prosthesis. This operation is problematic. The consequence is that the femoral condyle and intercondyle are osteotomized together, making it impossible to measure the femur in advance. When it is discovered that the femoral condyle trial mold is installed in the femur for matching and to determine the size of the femoral condyle prosthesis, and it is found that the model is incorrect, it is impossible to perform secondary processing of the femoral condyle or intercondyle. This is because the integrated design of the femoral condyle trial mold and intercondyle trial mold has already processed the femoral condyle and intercondyle. Secondary processing would result in multiple osteotomies, and the femoral condyle prosthesis would have a poor match with the femur, leading to postoperative pain and discomfort for the patient.

[0042] Therefore, after the four-in-one osteotomy in knee replacement surgery, a surgical instrument is needed to measure the size of the osteotomy surface before the intercondylar section is removed to match the patient's skeletal physiology, and to measure the patient's intercondylar size after the osteotomy. This instrument should be convenient to install, securely fix, and easy to disassemble, allowing the surgeon to accurately and quickly select and install the appropriate femoral condyle prosthesis. Currently available surgical instruments on the market are inconvenient to use for femoral condyle trial molding, have low safety, and are difficult to select and assemble, resulting in increased operation time, inaccurate assessment of condyle size, and affecting surgical outcomes. Therefore, the femoral condyle trial molding and intercondylar trial molding assembly method needs to be redesigned for this surgical procedure. This solution is an instrument designed specifically for this surgical procedure.

[0043] This invention provides a detachable locking structure for a femoral condyle trial mold and an intercondylar trial mold, such as... Figure 1-10 As shown, the femoral condyle mold 1 has an intercondylar groove 11 in the middle, and the intercondylar mold 2 is detachably connected to the intercondylar groove 11, wherein:

[0044] Positioning grooves 12 are provided on the left and right sides in front of the intercondylar groove 11 (i.e., the left and right positions of the center of the intercondylar region of the femoral condyle at the patellar trochlea 15 of the femoral condyle test mold 1). The positioning grooves 12 are used to quickly position the front side of the detachable intercondylar test mold 2. A cam 13 (CAM) is provided at the rear of the intercondylar groove 11. The cam 13 is used to cooperate with the post on the tibial component of the knee joint prosthesis. The cam 13 is provided with positioning holes 131. The positioning holes 131 are used to quickly position the rear side of the intercondylar test mold 2.

[0045] The front end of the intercondylar mold 2 (i.e., the patellar trochlea 15 near the femoral condyle mold 1) is provided with a positioning boss 21 that cooperates with the positioning groove 12, and the rear end of the intercondylar mold 2 (i.e., the posterior condyle near the femoral condyle mold 1) is provided with a retractable positioning post 22 that cooperates with the positioning hole 131.

[0046] It should be noted that in this application, the position reference is based on the state of a person standing.

[0047] In use, after the four-in-one osteotomy, when the femoral condyle template 1 and intercondylar template 2 need to be used together, insert the positioning boss 21 at the front end of the intercondylar template 2 into the positioning groove 12 of the femoral condyle template 1, and at the same time retract the positioning post 22 at the rear end of the intercondylar template 2, and place the entire intercondylar template 2 into the intercondylar groove 11 of the femoral condyle template 1. Then, extend the positioning post 22 at the rear end of the intercondylar template 2 and insert it into the positioning hole 131 on the cam 13 of the femoral condyle template 1 to fix it, and perform simultaneous measurement of the femoral condyle and the intercondylar region. When the four-in-one osteotomy is completed and the measurement of the intercondylar template 2 is no longer needed, disassemble the intercondylar template 2 in reverse order of use to measure the size of the femoral condyle.

[0048] The detachable locking structure of the femoral condyle and intercondylar trial molds of this invention is mainly used to evaluate the size and dimensions of the osteotomy surface after a four-in-one osteotomy in knee replacement surgery, before the intercondylar section is cut, to ensure it matches the patient's skeletal physiology (femoral condyle trial mold 1 is used alone in this case), and after the intercondylar osteotomy, to measure the size and dimensions of the patient's intercondylar section (femoral condyle trial mold 1 and intercondylar trial mold 2 are used together in this case). It is convenient to install, securely fixed, easy to disassemble, reusable, safe, reliable, and allows doctors to accurately and quickly select a suitable femoral condyle prosthesis for implantation. In this invention, the positioning grooves and positioning holes work together, with the two positioning grooves and the positioning holes forming a triangular positioning (see...). Figure 5 The triangular fixing mechanism 16) restricts six degrees of freedom: left and right, front and back, and up and down, which firmly fixes the intercondylar mold and increases the fixation effect of the detachable intercondylar mold. This triangular fixing and positioning principle is safer, more secure, easier to install and assemble, and saves surgical time than the methods used in current technologies.

[0049] like Figure 2As shown, the line La connecting the center point of the patellar trochlea 15 of the femoral condyle model 1 and the positioning groove 12, and the vertical center line Lb of the femoral condyle model 1 when the person is standing, the included angle A between these two lines can be 60°, and the positioning groove 12 is in this position when the effect is best.

[0050] like Figure 3-4 and Figure 6 As shown, the distance L1 between the outer edges of the two positioning grooves 12 and the width H1 of the intercondylar mold 2 can both be 20mm to 40mm, and can be flexibly selected as needed, such as 25mm, 30mm, 35mm, etc. The widths LL1, LL2 of each positioning groove 12 and the widths HH1, HH2 of the positioning boss 21 can both be 4mm to 10mm, such as 5mm, 7mm, 9mm, etc. The diameter φA of the positioning hole 131 and the diameter φB of the positioning post 22 can both be 2mm to 6mm, such as 3mm, 4mm, 5mm, etc.

[0051] To facilitate the insertion of the positioning pin 22 into the positioning hole 131, the inner side of the cam 13 may be provided with a guide groove 132 for guiding the positioning pin 22 to slide into the positioning hole 131. The cross-section of the guide groove 132 may be an arc with a radius of 1mm to 6mm, such as 2mm, 3mm, 4mm, etc.

[0052] To enable the retractable positioning post 22 at the rear end of the intercondylar trial mold 2, various structural forms readily conceived by those skilled in the art can be adopted. For ease of implementation, the present invention preferably adopts the following structural form:

[0053] like Figure 6-8 As shown, the intercondylar test mold 2 is equipped with a trolley device 3. The trolley device 3 includes a slide 31 extending in the front-rear direction and a slider 32 located in the slide 31. The rear end of the slider 32 is connected to the positioning post 22. An elastic element is provided between the front end of the slider 32 and the front side wall of the slide 31 to push the slider 32 so that the positioning post 22 extends. The elastic element enables the trolley device 3 to achieve an automatic locking function.

[0054] To facilitate pushing the slider 32 to extend the positioning pin 22, various methods can be used, such as providing an anti-slip texture on the surface of the slider 32. However, for ease of operation, the slider 32 preferably has an ergonomically designed hand-held hole 321, the radius of which can be 5.5mm. The elastic element can be a spring 33, in which case a spring fixing pin 34 can be provided on the front side wall of the slide 31 to securely fix the spring 33.

[0055] At this point, the assembly sequence of the femoral condyle model 1 and the intercondylar model 2 in this invention can be as follows:

[0056] 1. For example Figure 9As shown in (a), the positioning boss 21 at the front end of the intercondylar test mold 2 is first inserted into the positioning groove 12 of the femoral condyle test mold 1;

[0057] 2. For example Figure 9 As shown in (b), the index finger then drives the hand-pressing hole 321. Under the driving action of the index finger, the slider 32 slides forward on the slide rail 31, compressing the spring 33. Since the rear end of the slider 32 is connected to the positioning post 22, the positioning post 22 at the rear end of the intercondylar mold 2 contracts.

[0058] 3. Continue as follows Figure 9 As shown in (b), the entire intercondylar mold 2 is placed into the intercondylar groove 11 of the femoral condylar mold 1. The guide groove 132 on the inner side of the cam 13 on the femoral condylar mold 1 guides the positioning post 22 at the rear end of the intercondylar mold 2 to slide into the positioning hole 131. Then, the slider 32 of the intercondylar mold 2 is released, and the spring 33 rebounds. Driven by the elastic force of the spring 33, the slider 32 slides backward on the slide rail 31. Since the rear end of the slider 32 is connected to the positioning post 22, the positioning post 22 at the rear end of the intercondylar mold 2 extends out and inserts into the positioning hole 131 to achieve fixation.

[0059] Finally, the structure of the assembled femoral condyle model 1 and intercondylar model 2 is as follows: Figure 10 As shown.

[0060] To facilitate limiting the slider 32 and prevent it from coming out of the slide rail 31, the side of the slider 32 may be provided with a limiting groove 35 extending in the front-back direction, and a limiting pin 36 is provided on the side wall of the slide rail 31, with the end of the limiting pin 36 extending into the limiting groove 35.

[0061] The anterior wall of intercondylar mold 2 can be 40°-50° (see Figure 7 The inclined surface of the middle angle B) is preferably 45° to facilitate a firm fit with the femoral condyle mold 1. The surface of the positioning boss 21 near the front wall of the intercondylar mold 2 may be provided with a guide arc 211 to facilitate the insertion of the positioning boss 21 on the intercondylar mold 2 into the positioning groove 12 of the femoral condyle mold 1.

[0062] like Figure 7-8 and Figure 10 As shown, both the slide 31 and the slider 32 can be lower at the rear and higher at both ends to facilitate matching with the tibial component of the knee joint prosthesis. The intercondylar mold 2 can be provided with a pair of sidewalls 23 above the trolley device 3. The middle of the pair of sidewalls 23 is provided with an upwardly extending extension 231 to better fit the intercondylar groove 11 of the femoral condyle mold 1 and improve the installation stability.

[0063] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A detachable locking structure for a femoral condyle trial mold and an intercondylar trial mold, characterized in that, The femoral condyle mold has an intercondylar groove in its middle, and the intercondylar mold is detachably connected to the intercondylar groove, wherein: The intercondylar groove is provided with positioning grooves on the left and right sides in front, and a cam is provided at the rear of the intercondylar groove, with positioning holes on the cam; The front end of the intercondylar mold is provided with a positioning boss that mates with the positioning groove, and the rear end of the intercondylar mold is provided with a retractable positioning post that mates with the positioning hole. The intercondylar test mold is equipped with a trolley device, which includes a slide rail extending in the front-to-back direction and a slider located in the slide rail. The rear end of the slider is connected to the positioning post, and an elastic element for pushing the slider to extend the positioning post is provided between the front end of the slider and the front side wall of the slide rail.

2. The detachable locking structure between the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The line connecting the center point of the patellar trochlea of ​​the femoral condyle model and the positioning groove, and the vertical center line of the femoral condyle model when the person is standing, the included angle between the two lines is 60°.

3. The detachable locking structure between the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The distance between the outer edges of the two positioning grooves and the width of the intercondylar mold are both 20mm to 40mm; And / or, the width of each positioning groove and positioning boss is 4mm to 10mm; And / or, the diameters of the positioning holes and positioning pins are both 2mm to 6mm.

4. The detachable locking structure between the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The inner side of the cam is provided with a guide groove for guiding the positioning pin to slide into the positioning hole.

5. The detachable locking structure for the femoral condyle trial mold and the intercondylar trial mold according to claim 4, characterized in that, The cross-section of the guide groove is an arc with a radius of 1mm to 6mm.

6. The detachable locking structure for the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The slider is equipped with ergonomically designed hand-operated holes.

7. The detachable locking structure for the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The elastic element is a spring, and a spring fixing post is provided on the front side wall of the slide rail; And / or, the slider has a limiting groove extending in the front-to-back direction on its side, and the slide rail has a limiting pin on its side wall, with the end of the limiting pin extending into the limiting groove.

8. The detachable locking structure for the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, The front wall of the intercondylar mold is an inclined surface of 40°-50°; And / or, the positioning boss has a guide arc on the surface near the front wall of the intercondylar mold.

9. The detachable locking structure between the femoral condyle trial mold and the intercondylar trial mold according to claim 1, characterized in that, Both the slide rail and the slider are lower at the rear and higher at both ends; And / or, the intercondylar test mold is provided with a pair of sidewalls above the trolley device, and the middle of the pair of sidewalls is provided with an upwardly extending extension.

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