Distraction device for total knee arthroplasty

Abstract

The utility model provides a distraction device for total knee replacement surgery. The distraction device comprises a first holding distraction component, a second distraction component and a second holding component, wherein the first holding distraction component comprises a first distraction part used for distraction of a knee joint, a first holding part used for holding and a first connecting part used for connecting the first distraction part and the first holding part; the second distraction component comprises a second distraction part for distraction of the knee joint, a pushed part and a second connecting part for connecting the second distraction part and the pushed part; the second holding component comprises a second holding part used for holding, a pushing assembly used for pushing the pushed part to enable the first distraction part and the second distraction part to be distraction, and a third connecting part connected with the second holding part. The first connecting part, the second connecting part and the third connecting part are mutually hinged; the dilator further comprises a locking assembly used for locking the first distraction part and the second distraction part in the distraction state, and the locking assembly is fixedly installed on the first connecting part.

Description

Technical Field

[0001] This utility model belongs to the field of medical devices and relates to a spreader for total knee replacement surgery, used to spread the gap between the knee joint (femur and tibia) during total knee replacement surgery. Background Technology

[0002] Soft tissue balance in the knee joint is crucial for the success of total knee arthroplasty (TKA). Soft tissue balance refers to the balance of the medial and lateral joint spaces achieved during surgery through techniques such as osteotomy, adjustment of joint line height, and soft tissue release, thereby achieving joint stability and functional recovery. Soft tissue balance is one of the key factors for the success of TKA, affecting the long-term stability and function of the prosthesis. Therefore, surgeons need to perform meticulous procedures to ensure soft tissue balance is achieved. Failure to achieve soft tissue balance after TKA may lead to postoperative pain, limited range of motion, and instability; further, it may cause abnormal wear and aseptic loosening of the prosthesis, affecting long-term prognosis. If knee arthroplasty relies primarily on the surgeon's subjective judgment of soft tissue balance, the accuracy is particularly low, and the amount of experience has little impact on the accuracy of the judgment.

[0003] To facilitate real-time observation of the opening distance and opening force by surgeons, Chinese patent application No. 201810241696.5 discloses a knee joint space opener. The opener has a scale plate on the middle clamp handle for intuitive measurement of the opening distance. The opener is also equipped with a tension gauge to accurately measure the tension of the opener, allowing for real-time monitoring of the patient's ligament tension and ensuring the safety of the treatment.

[0004] Although the above-mentioned spreader can monitor the spreading distance and spreading force in real time, it still has some drawbacks: 1. The tension gauge will shake during the operation, making it inconvenient to observe; 2. The ratchet locking mechanism at the tail is much wider than the handle, which is inconvenient to operate, easy to injure the user, and also inconvenient to store. Utility Model Content

[0005] In view of the above-mentioned deficiencies of the prior art, the present invention provides a retractor for total knee replacement surgery. The technical problem to be solved is to realize the ability to observe the retraction distance and retraction force in real time during the operation, and to shorten the length of the rack in the existing locking mechanism for easy operation and storage.

[0006] To solve the above problems, the technical solution adopted by this utility model is: a spreader for total knee replacement surgery, comprising a first gripping and spreading member, a second spreading member, and a second gripping member; wherein,

[0007] The first gripping and spreading member includes a first spreading part for spreading the knee joint, a first gripping part for gripping, and a first connecting part for connecting the first spreading part and the first gripping part;

[0008] The second spreading member includes a second spreading part for spreading the knee joint, a pushed part, and a second connecting part for connecting the second spreading part and the pushed part;

[0009] The second gripping member includes a second gripping part for gripping, a pushing component for pushing the pushed part to open the first opening part and the second opening part, and a third connecting part connected to the second gripping part;

[0010] The first connecting part, the second connecting part, and the third connecting part are hinged to each other;

[0011] The expander further includes a locking component for locking the first expander portion and the second expander portion in the expanded state, the locking component being fixedly installed on the first connecting portion.

[0012] Preferably, the surfaces of the first and second spreading portions are provided with protrusions to increase the frictional force of contact.

[0013] Preferably, the pushing component is located inside the second gripping portion.

[0014] Preferably, the pushing assembly includes a pushing spring and a pushing spring sleeve shaft; the pushing spring sleeve shaft is fixedly installed on the inner side of the second gripping part, the pushing spring is sleeved on the pushing spring sleeve shaft, one end of the pushing spring is used to abut against the second gripping part, and the other end is used to abut against the pushed part.

[0015] Preferably, the pushing component further includes a pressure spring dial for displaying the pressure exerted on the first and second opening portions.

[0016] Preferably, the spreader further includes a return spring located between the first gripping spreader and the second spreader, for providing a return force.

[0017] Preferably, the reset spring is a U-shaped spring sheet, with one end abutting against the inner side of the first connecting part and the other end abutting against the side of the second connecting part.

[0018] Preferably, the locking assembly includes a ratchet rack, a pawl, and a pawl retainer; the pawl retainer acts on the pawl with elastic force, causing the pawl to abut against the ratchet teeth on the ratchet rack, thereby achieving locking.

[0019] Preferably, the ratchet is fixedly installed on the inner side of the first connecting part and extends toward the second gripping member, passing through the through hole on the second connecting part and extending to the through hole on the third connecting part.

[0020] Preferably, the ratchet rack is further provided with a scale for displaying the opening distance between the first opening portion and the second opening portion.

[0021] The beneficial effects of this invention are as follows: By displaying the spreading distance and spreading force, the retractor helps surgeons accurately measure and assess the soft tissue tension of the knee joint in different flexion and extension states. Through the real-time feedback from the retractor, surgeons can determine whether the soft tissue has reached an ideal balance, i.e., whether the joint space is uniform in extension and flexion. The unidirectional locking design prevents accidental rebound, reducing the risk of soft tissue injury during surgery and ensuring patient safety. Furthermore, the locking mechanism's rack is located in the middle of the entire instrument, significantly shortening the rack's length and facilitating operation and storage. The retractor provided by this invention can also serve as a teaching tool, helping junior surgeons better understand the concept and importance of soft tissue balance and replicate the surgical experience of senior surgeons. By using the retractor to ensure soft tissue balance, the success rate of TKA surgery can be improved, postoperative pain reduced, joint function improved, and the risk of complications lowered.

[0022] The following will further explain the concept, specific structure and technical effects of this utility model in conjunction with the accompanying drawings, so as to fully understand the purpose, features and effects of this utility model. Attached Figure Description

[0023] Figure 1 This is a front structural schematic diagram of a preferred embodiment of the retractor for total knee replacement surgery provided by this utility model.

[0024] Figure 2 for Figure 1 The diagram shows the back structure of a spreader used in total knee replacement surgery.

[0025] Figure 3 for Figure 1 The diagram shows a cross-sectional view of the locking assembly of a spreader used in total knee replacement surgery.

[0026] Explanation of reference numerals in the attached figures:

[0027] 100—First gripping and spreading component; 110—First spreading part;

[0028] 120—First gripping part, 130—First connecting part,

[0029] 200—Second support member, 210—Second support portion,

[0030] 220—Propelled part, 230—Second connecting part,

[0031] 300—Second gripping component, 310—Pushing component,

[0032] 311—Push spring, 312—Push spring bushing shaft,

[0033] 313—Push spring dial; 320—Second grip;

[0034] 330—Third connecting part, 400—Return spring,

[0035] 500—Locking assembly, 510—Ratchet,

[0036] 520—Pawl; 530—Pawl retainer. Detailed Implementation

[0037] Figures 1-3 This invention illustrates a preferred embodiment of the retractor for total knee replacement surgery provided by this invention.

[0038] like Figures 1-2 As shown, the retractor for total knee replacement surgery in this specific embodiment includes a first gripping and retracting member 100 and a second retracting member 200. The first gripping and retracting member 100 includes a first retracting portion 110, and the second retracting member 200 includes a second retracting portion 210. The function of the first retracting portion 110 and the second retracting portion 210 is to directly contact the femur and tibia of the knee joint, thereby retracting the joint gap. To increase the frictional force of the contact, protrusions are also provided on the surfaces of the first retracting portion 110 and the second retracting portion 210.

[0039] The first gripping and opening member 100 includes a first opening portion 110, a first grip portion 120, and a first connecting portion 130. The first grip portion 120, together with the second grip portion (described below), is used by the user for gripping and to open the first opening portion 110 and the second opening portion 210. The first connecting portion 130 connects the first opening portion 110 and the first grip portion 130. Furthermore, the first connecting portion 130 is hinged to the second opening member 200, allowing the first connecting portion 130 and the second opening member 200 to rotate relative to each other, thereby enabling the opening of the first opening portion 110 and the second opening portion 210.

[0040] The second spreading member 200 includes a second spreading portion 210, a pushed portion 220, and a second connecting portion 230. The pushed portion 220 is pushed by the second gripping member (described below), causing relative rotation between the first gripping spreading member 100 and the second spreading member 200, thereby spreading the first spreading portion 110 and the second spreading portion 210. The second connecting portion 230 is hinged to the first connecting portion 130, thus achieving a hinge between the first connecting portion 130 and the second spreading member 200.

[0041] The retractor for total knee replacement surgery in this specific embodiment also includes a second gripping member 300. The function of the second gripping member 300, together with the first gripping part mentioned above, is for the user to grip and push the pushed part 220 of the second retractor 200, thereby realizing the retracting operation of the first retractor 110 and the second retractor 210. Specifically, the second gripping member 300 includes a pushing component 310, a second gripping part 320, and a third connecting part 330. The second gripping part 320 is used for the user to grip; the pushing component 310 is located inside the second gripping part 320 and is used to push the pushed part 220 of the second retractor 200; the third connecting part 330 is hinged to the first connecting part 130 and the second connecting part 230, thereby realizing the relative rotation of the second gripping member 300 with respect to the first gripping retractor 100 and the second retractor 200, so as to push the pushed part 220 of the second retractor 200. The pushing assembly 310 includes a pushing spring 311, a pushing spring sleeve shaft 312, and a pushing spring dial 313. One end of the pushing spring 311 is used to abut against the inner side of the second gripping part 320, and the other end is used to abut against the pushed part 220 of the second spreading member 200. When the user grips the first gripping part 120 and the second gripping part 320 and performs a squeezing operation, the distance between the second gripping part 320 and the pushed part 220 decreases. The pushing spring 311 then pushes the pushed part 220 to rotate towards the first gripping part 120, thereby increasing the distance between the first spreading part 110 and the second spreading part 210 to achieve the spreading operation. A push spring sleeve shaft 312 is fixedly installed inside the second grip portion 320, and a push spring 311 is sleeved on the push spring sleeve shaft 312. Additionally, the pushed portion 220 of the second spreading member 200 is provided with a push spring sleeve shaft through hole that matches the push spring sleeve shaft 312, and the distal end of the push spring sleeve shaft 312 extends into the push spring sleeve shaft through hole. A push spring dial 313 is fixedly installed on the second grip portion 320, with its distal end extending into the pushed portion 220 of the second spreading member 200, and is used to display the pressure received by the first spreading portion 110 and the second spreading portion 210 based on the distance between the second grip portion 320 and the pushed portion 220.

[0042] The retractor for total knee replacement surgery in this specific embodiment also includes a return spring 400. The return spring 400 is located between the first gripping retractor 100 and the second retractor 200, and its function is to provide a return force so that when the first gripping retractor 100 and the second retractor 200 are not subjected to external force, the first retractor 110 and the second retractor 210 are in a tightly fitted state. Figure 1 and Figure 2 As shown, in this specific embodiment, the reset spring 400 is a U-shaped spring sheet, with one end abutting against the inner side of the first connecting portion 130 of the first gripping and spreading member 100, and the other end abutting against the side of the second connecting portion 230 of the second spreading member 200.

[0043] like Figures 1-3As shown, the retractor for total knee replacement surgery in this specific embodiment also includes a locking component 500. The function of the locking component 500 is to lock the first retractor 110 and the second retractor 210 in the retracted state. When the user grips the first grip 120 and the second grip 320 and performs a squeezing operation, the first retractor 110 and the second retractor 210 are in the retracted state. When the user releases the first grip 120 and the second grip 320, due to the action of the locking component 500, the first retractor 110 and the second retractor 210 are locked in the corresponding retracted state. Specifically, the locking component 500 includes a ratchet rack 510, a pawl 520, and a pawl retainer 530. The ratchet rack 510 is fixedly installed on the inner side of the first connecting portion and extends toward the second grip member 300, passing through a through hole on the second connecting portion 230 and extending to a through hole on the third connecting portion 330. The pawl 520 is located in the through hole of the third connecting part 330 and is hinged to the third connecting part 330. The pawl retainer 530 is a spring plate that abuts against the pawl 520 through elastic force, causing the pawl 520 to stop at the ratchet tooth on the ratchet rack 510, thereby achieving locking. When the user holds the first grip part 120 and the second grip part 320 to perform a pressing operation, the third connecting part 330 drives the pawl 520 to slide towards the first grip opening member 100; when the user releases the first grip part 120 and the second grip part 320, due to the elastic force of the pawl retainer 530, the pawl 520 abuts against the corresponding ratchet tooth on the ratchet rack 510, thereby achieving locking. To release the lock and return the first gripping and opening member 100 and the second gripping member 300 to their initial state (i.e., the first opening part 110 and the second opening part 210 are tightly engaged), the tail of the pawl 520 can be pressed. This causes the pawl 520 to rotate relative to the second gripping member 300 and disengage from the ratchet rack 510. Then, under the elastic force of the return spring 400, the first gripping and opening member 100 and the second gripping member 300 can return to their initial state. The locking design prevents accidental rebound, reduces the risk of soft tissue injury during surgery, and ensures patient safety. The rack of the locking mechanism is located in the middle of the entire instrument, greatly shortening the rack's length and facilitating operation and storage.

[0044] In addition, the ratchet rack 510 is equipped with a scale to display the distance between the first spreading section 110 and the second spreading section 210. By displaying the spreading distance and spreading force, surgeons can accurately measure and assess the soft tissue tension of the knee joint in different flexion and extension states. Through the real-time feedback from the spreader, doctors can determine whether the soft tissue has reached an ideal balance, that is, whether the joint space is uniform in extension and flexion.

[0045] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A retractor for total knee replacement surgery, characterized in that, It includes a first gripping and spreading member, a second spreading member, and a second gripping member; wherein, The first gripping and spreading member includes a first spreading part for spreading the knee joint, a first gripping part for gripping, and a first connecting part for connecting the first spreading part and the first gripping part; The second spreading member includes a second spreading part for spreading the knee joint, a pushed part, and a second connecting part for connecting the second spreading part and the pushed part; The second gripping member includes a second gripping part for gripping, a pushing component for pushing the pushed part to open the first opening part and the second opening part, and a third connecting part connected to the second gripping part; The first connecting part, the second connecting part, and the third connecting part are hinged to each other; The expander further includes a locking component for locking the first expander portion and the second expander portion in the expanded state, the locking component being fixedly installed on the first connecting portion.

2. The retractor for total knee replacement surgery as described in claim 1, characterized in that, The surfaces of the first and second spreading portions are provided with protrusions to increase the frictional force of contact.

3. The retractor for total knee replacement surgery as described in claim 1, characterized in that, The pushing component is located inside the second gripping part.

4. The retractor for total knee replacement surgery as described in claim 1, characterized in that, The pushing assembly includes a pushing spring and a pushing spring sleeve shaft; the pushing spring sleeve shaft is fixedly installed on the inner side of the second gripping part, the pushing spring is sleeved on the pushing spring sleeve shaft, one end of the pushing spring is used to abut against the second gripping part, and the other end is used to abut against the pushed part.

5. The retractor for total knee replacement surgery as described in claim 4, characterized in that, The pushing component also includes a pressure spring dial for displaying the pressure applied to the first and second opening portions.

6. The retractor for total knee replacement surgery as described in claim 1, characterized in that, The spreader also includes a return spring located between the first gripping spreader and the second spreader, for providing a return force.

7. The retractor for total knee replacement surgery as described in claim 6, characterized in that, The reset spring is a U-shaped spring sheet, with one end abutting against the inner side of the first connecting part and the other end abutting against the side of the second connecting part.

8. The retractor for total knee replacement surgery as described in claim 1, characterized in that, The locking assembly includes a ratchet rack, a pawl, and a pawl retainer; the pawl retainer acts on the pawl with elastic force, causing the pawl to abut against the ratchet teeth on the ratchet rack, thereby achieving locking.

9. The retractor for total knee replacement surgery as described in claim 8, characterized in that, The ratchet is fixedly installed on the inner side of the first connecting part and extends toward the second gripping member, passing through the through hole on the second connecting part and extending to the through hole on the third connecting part.

10. The retractor for total knee arthroplasty as described in claim 8, characterized in that, The ratchet rack is also provided with a scale for displaying the opening distance between the first opening part and the second opening part.

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