Knee prosthesis snap-fit ​​device

Abstract

The present invention discloses a knee joint prosthesis clamping device, comprising: a shell, which has a first accommodating cavity inside, and a first hole is respectively provided at the front and rear ends; an extension portion extending distally from the shell, and the distal end of which forms a stopper downward; a push rod arranged behind the stopper and passing through the first hole, a pad block is provided at the distal end of the push rod, and a ratchet arranged along the axial direction of the push rod is provided on the push rod; a non-return pawl arranged in the first accommodating cavity and fixed in position, and a push block sleeved on the push rod and movable forward and backward, the push block has an active pawl, and the ratchet is respectively engaged with the active pawl and the non-return pawl; a grip and a trigger arranged below the shell, and the upper end of the trigger is engaged with the push block; and a locking component, which is configured to limit the rotation of the push rod and release the restriction on the rotation of the push rod. The pistol-type design is convenient for doctors to operate; the trigger lever-type structure allows surgeons to push the tibial pad into the tibial tray with little effort; an intermittent pushing mechanism is adopted, which is convenient for doctors to stop at any time to observe the clamping state.

Description

Technical Field

[0001] The invention relates to surgical instruments, in particular to a knee joint prosthesis snap-fitting device. Background Art

[0002] Arthroplasty is a well-known surgical procedure used to replace a patient's damaged natural joint with a prosthetic joint. A typical knee prosthesis includes a patellar prosthetic component, a tibial tray, a femoral component, and a polymer insert or support positioned between the tibial tray and the femoral component. The tibial side of the knee prosthesis includes a metal tibial tray and a plastic tibial pad, which are snap-fitted to each other. In order to firmly connect the tibial tray and the tibial pad, the snap-fitting part of the two is designed to be very tight, which causes the problem that the surgeon needs to use a lot of force to push the tibial pad into the tibial tray. Summary of the invention

[0003] In order to solve at least one technical problem in the prior art, the present invention provides a knee joint prosthesis engaging device.

[0004] A knee prosthesis engaging device, characterized in that it comprises: an outer shell having a first accommodating cavity inside, and first holes are respectively provided at the front and rear ends of the outer shell; an extension portion extending distally from the outer shell, and the distal end of the extension portion forms a stop member downward; a push rod arranged behind the stop member and passing through the first hole, a pad block opposite to the stop member is provided at the distal end of the push rod, and ratchets are arranged axially along the push rod; a check pawl and a push block arranged in the first accommodating cavity, the position of the check pawl is fixed, the push block is sleeved on the push rod and can move forward and backward, an active pawl is provided in the push block, and the ratchets are respectively engaged with the active pawl and the check pawl; a handle and a rotatable trigger are arranged under the outer shell, the upper end of the trigger extends into the first accommodating cavity and engages with the push block for actuating the push block; and a locking member, which is configured to limit the rotation of the push rod and release the restriction on the rotation of the push rod.

[0005] The beneficial effects of this embodiment are: holding the handle and the trigger, driving the push rod forward by pulling the trigger to push the tibial pad toward the tibial tray, which is convenient for the surgeon to operate; the trigger lever structure allows the surgeon to push the tibial pad into the tibial tray with less effort; the intermittent pushing mechanism using a check pawl, an active pawl and ratchets makes it easy for the surgeon to stop at any time to observe the assembly status of the tibial pad and the tibial tray.

[0006] In some embodiments, the check pawl is rotatably connected to the housing below the push rod, the pawl head of the check pawl is arranged forward relative to the pawl tail, the pawl tail of the check pawl is applied a forward force by the second spring, and in the locked state, the pawl head of the check pawl is engaged with the ratchet; the active pawl is rotatably connected to the push block below the push rod, the pawl head of the active pawl is arranged forward relative to the pawl tail, the pawl tail of the active pawl is applied a forward force by the first spring, and in the locked state, the pawl head of the active pawl is engaged with the ratchet.

[0007] In some embodiments, the push rod is a round rod and has a plane section extending axially along the push rod formed on its surface. The locking component includes a locking plate located inside the shell and a rotating rod located outside the shell. One end of the locking plate is connected to the rotating rod through a rotating pin, and the other end of the locking plate is close to the plane section. The rotating pin penetrates the wall of the shell in a direction perpendicular to the plane section and can rotate relative to the shell around the central axis of the rotating pin. The end of the locking plate close to the plane section is provided with an arc-shaped notch facing the plane section.

[0008] In some embodiments, a limiting portion is also included, at least a portion of which is located within a quarter-cylindrical area swept by the locking plate when it rotates 90° from a state where the generatrix of the arc-shaped notch is perpendicular to the push rod to a state where the generatrix of the arc-shaped notch is parallel to the push rod, and two side plane boundaries of the quarter-cylindrical area are respectively aligned with the surfaces of the corresponding limiting portion.

[0009] In some embodiments, the rotating rod has an elastically retractable positioning pin, and the outer shell surface has a first positioning groove and a second positioning groove that can be concavely matched with the retractable end of the positioning pin; in the locked state, the positioning pin cooperates with the first positioning groove; in the unlocked state, the positioning pin cooperates with the second positioning groove.

[0010] In some embodiments, the lower part of the trigger is provided with a torsion spring, which applies a forward force to the lower part of the trigger; the upper part of the trigger has a pair of trigger arms arranged at intervals, and the ends of the trigger arms are provided with notches, and the left and right sides of the push block are provided with pins, the push block is placed between the two trigger arms, and the pins are freely inserted into the notches of the corresponding trigger arms.

[0011] In some embodiments, the stop component includes a first component and a second component, the second component is arranged behind the first component, the upper end of the second component is rotatably connected to the extension part, a fixing pin is provided on the rear side of the first component, the fixing pin passes through the second component and a limiting protrusion is provided at the free end of the fixing pin to limit the second component from detaching from the fixing pin, and a reset spring is also provided between the first component and the second component and is sleeved on the fixing pin.

[0012] In some embodiments, the front surface of the pad is configured to be an arc shape that matches the rear edge of the tibial pad. The pad is made of plastic and is clamped on a metal base that is connected to the front end of the push rod through a pin.

[0013] In some embodiments, the rotating rod extends in a direction perpendicular to a generatrix of the arc-shaped notch. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional view of a knee joint prosthesis engaging device according to one embodiment of the present invention.

[0015] Figure 2 The figure is an exploded view of a knee joint prosthesis engaging device according to one embodiment of the present invention.

[0016] Figure 3 It is a cross-sectional view of a knee joint prosthesis engaging device according to one embodiment of the present invention.

[0017] Figure 4 It is a top view of a knee joint prosthesis engagement device in an unlocked state according to one embodiment of the present invention.

[0018] Figure 5 for Figure 4 Middle BB section view.

[0019] Figure 6 It is a top view of a knee joint prosthesis engagement device in a locked state according to an embodiment of the present invention.

[0020] Figure 7 for Figure 6 Middle CC section view.

[0021] Explanation of symbols:

[0022] Shell 1, extension part 2, push rod 3, grip 4, trigger 5, locking component 6, stop component 7, cushion block 8, first accommodating chamber 9, first hole 10, check pawl 11, push block 12, active pawl 13, ratchet 14, second accommodating chamber 15, second hole 16, first pin 17, first spring 18, second pin 19, second spring 20, third pin 21, trigger arm 22, torsion spring 23, notch 24, pin 25, locking plate 26, rotating rod 27, rotating pin 28, arc-shaped notch 29, flat cut surface 30, positioning pin 31, first positioning groove 32, second positioning groove 33, metal base 34, pin 35, first component 36, second component 37, fixing pin 38, limiting protrusion 39, reset spring 40, side circumference 41, side plate 42, limiting part 43 DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0024] The present invention provides a knee joint prosthesis engaging device, which is in the shape of a pistol that is easy to operate. The tibial pad is pushed into the tibial tray by pulling a trigger 5, which is easy to operate and labor-saving.

[0025] Figure 1 is a stereoscopic view of a knee prosthesis engagement device in some embodiments. Figure 1 It can be seen that the knee joint prosthesis engaging device comprises a housing 1, an extension portion 2 extending distally from the housing 1, a push rod 3 penetrating the housing 1 and extending in the front-to-back direction, a handle 4 and a trigger 5 arranged below the housing 1, and a locking component 6. The distal end of the extension portion 2 forms a stop component 7 downward, the push rod 3 is arranged behind the stop component 7, and the distal end of the push rod 3 has a pad 8 opposite to the stop component 7. A one-way transmission mechanism is provided in the housing 1, and the one-way transmission mechanism is engaged with the push rod 3 to push the push rod 3 intermittently to the distal side in one direction. The trigger 5 is engaged with the one-way transmission mechanism, and when the trigger 5 is pulled, the one-way transmission mechanism is triggered, so that the one-way transmission mechanism pushes the push rod 3 toward the stop component 7. Manual operation of the locking component 6 can make the locking component 6 enter a locked state and an unlocked state respectively. In the locked state, the locking component 6 constrains the push rod 3 to keep the push rod 3 in an engaged state with the one-way transmission mechanism, so that the one-way transmission mechanism can transmit the triggering of the trigger 5 to the push rod 3 to intermittently push the push rod 3 toward the distal side in one direction; in the unlocked state, the locking component 6 disengages from the push rod 3, so that the push rod 3 is disengaged from the one-way transmission mechanism.

[0026] When using the device to assemble the tibial tray and the tibial pad, the front edge of the tibial pad is placed in advance into the groove of the tibial tray, and then the tibial tray is placed against the stop component 7, and the pad 8 is placed against the rear edge of the tibial pad. Then, by repeatedly pulling the trigger 5, the push rod 3 is intermittently pushed distally, thereby gradually pushing the tibial pad into the tibial tray.

[0027] Figure 2 An exploded view of a knee prosthesis snap-fit ​​device in some embodiments is shown. Figure 3 A longitudinal cross-sectional view of a knee prosthesis engagement device in some embodiments is shown, namely Figure 4 Please refer to the AA section in Figure 2 The housing 1 includes a side enclosure 41 surrounding the front, top and rear sides and side panels 43 arranged on both sides of the side enclosure. The side enclosure 41 and the side panels 42 form a Figure 3 The first accommodating cavity 9 is shown. Please refer to Figure 2 and Figure 3 The front and rear ends of the housing 1 are respectively provided with first holes 10 aligned with each other, and the push rod 3 passes through the pair of first holes 10 and is loosely matched with the first holes 10. The pair of first holes 10 keeps the push rod 3 able to move axially along the first holes 10 relative to the housing 1, and also limits the translation of the push rod 3 in the radial direction of the first holes 10.

[0028] A one-way transmission mechanism is disposed in the first accommodating chamber 9 of the housing 1, and the one-way transmission mechanism is configured to receive the power input by the trigger 5 and intermittently push the push rod 3 to the distal side in one direction. For example, please refer to Figure 2 and Figure 3 The one-way transmission mechanism includes a fixed non-return pawl 11 and a push block 12 that can move forward and backward, wherein the push block 12 has an active pawl 13. Ratchet teeth 14 are arranged axially on the outer wall of the push rod 3, and the non-return pawl 11 and the active pawl 13 are respectively engaged with the ratchet teeth 14 to achieve the engagement of the push rod 3 with the one-way transmission mechanism.

[0029] Please refer to Figure 3 The push block 12 is sleeved on the push rod 3. Specifically, a hollow second accommodating chamber 15 is provided in the push block 12. Second holes 16 are respectively provided at the front and rear ends of the push block 12. The push rod 3 passes through the pair of second holes 16 and is gap-matched with the pair of second holes 16, so that the push block 12 can slide along the axial direction of the push rod 3.

[0030] Please refer to Figure 2 and Figure 3 A rotatable active pawl 13 is disposed in the second accommodation cavity 15. For example, the active pawl 13 is rotatably connected to the push block 12 through a first pin shaft 17 perpendicular to the axial direction of the push rod 3. The active pawl 13 is biased by a first spring 18. Specifically, a first pin shaft 17 is disposed between the pawl head and the pawl tail of the active pawl 13. The pawl head of the active pawl 13 is disposed forward relative to the pawl tail. The pawl head of the active pawl 13 is engaged with the ratchet 14 on the push rod 3. The pawl tail of the active pawl 13 is connected to the first spring 18. The other end of the first spring 18 is connected to the position of the push block 12 in front of the pawl tail, so that the first spring 18 applies a pulling force biased forward to the pawl tail of the active pawl 13, and the pawl head of the active pawl 13 has a tendency to bias backward.

[0031] Please refer to Figure 2 and Figure 3 The non-return pawl 11 is rotatably arranged in the first accommodating cavity 9 of the housing 1. For example, the non-return pawl 11 is rotatably connected to the housing 1 through a second pin shaft 19 perpendicular to the axial direction of the push rod 3. The non-return pawl 11 is biased by a second spring 20. Specifically, a second pin shaft 19 is arranged between the pawl head and the pawl tail of the non-return pawl 11. The pawl head of the non-return pawl 11 is arranged forward relative to the pawl tail. The pawl head of the non-return pawl 11 is engaged with the ratchet 14 on the push rod 3, and the pawl tail of the non-return pawl 11 is connected to the second spring 20. The other end of the second spring 20 is connected to the housing 1 at a position in front of the pawl tail, so that the second spring 20 applies a pulling force biased forward to the pawl tail of the non-return pawl 11, and the pawl head of the non-return pawl 11 has a tendency to be biased backward.

[0032] When the push block 12 is pushed forward by the trigger 5, the active pawl 13 is engaged with the ratchet 14 on the push rod 3, and the push rod 3 is pushed forward by the push block 12. The non-return pawl 11 is rotated by the ratchet 14 and disengaged from the ratchet 14, so the non-return pawl 11 does not prevent the movement of the push rod 3. When the push block 12 moves in the reverse direction, the non-return pawl 11 and the ratchet 14 are engaged with each other to prevent the push rod 3 from moving backward. At the same time, the active pawl 13 is rotated by the ratchet 14 and disengaged from the ratchet 14, so the push block 12 can move backward while the push rod 3 remains stationary.

[0033] The grip 4 is fixed on the housing 1 and extends downward from the housing 1. The trigger 5 is located in front of the grip 4 and is rotatably arranged on the housing 1. Specifically, the trigger 5 is rotatably connected to the housing 1 through a third pin 21 extending in the left-right direction, so that the trigger 5 is constructed as a lever that rotates around the third pin 21. The upper half of the trigger 5 extends from the bottom of the housing 1 into the first accommodating chamber 9. The upper half of the trigger 5 is a pair of trigger arms 22 arranged at intervals, and the third pin 21 passes through the pair of trigger arms 22. The lower half of the trigger 5 is provided with a torsion spring. Specifically, the torsion spring 23 is sleeved on the third pin 21. One end of the torsion spring 23 abuts against the rear side of the trigger 5, and the other end abuts against the front side of the grip 4, applying a forward force to the lower half of the trigger 5. After the trigger 5 is pulled, when the external force is removed, the torsion spring 23 resets the trigger 5.

[0034] Please refer to Figure 3 , the upper end of the trigger 5 is configured to engage with the push block 12, so that the trigger 5 can move the push block 12 when it rotates. Specifically, the end of the trigger arm 22 of the trigger 5 is provided with a notch 24, and the left and right sides of the push block 12 are provided with a pin 25. The push block 12 is placed between the two trigger arms 22, and the pin 25 is freely inserted into the notch 24 of the corresponding trigger arm 22. Since the push block 12 is sleeved on the push rod 3, and the push rod 3 is limited in its vertical direction, the push block 12 is also limited in the direction perpendicular to the push rod 3, so the trigger 5 and the push block 12 can always maintain this engagement mode. The engagement mode of the trigger 5 and the push block 12 allows the pin 25 to move in the notch 24, so that the rotation of the trigger 5 can be converted into the linear motion of the push rod 3. In some embodiments, the rotation angle range of the trigger 5 is configured so that each time the trigger 5 is pulled, the push rod 3 can advance one ratchet 14 tooth pitch. The movable stroke of the push block 12 is related to the rotation angle range of the trigger 5, and the extension length of the notch 24 along the length direction of the trigger arm 22 limits the rotation angle range of the trigger 5, so the forward step length of the push rod 3 can be achieved by selecting a suitable notch 24 length.

[0035] When the trigger 5 is not pulled, the torsion spring 23 biases the trigger 5 in the initial state, and the push block 12 is against the rear end of the housing 1. When the trigger 5 is pulled, the trigger 5 rotates counterclockwise around the third pin 21, and the trigger arm 22 pushes the push block 12 forward, pushing the push rod 3 forward.

[0036] The locking component 6 switches between the locked state and the unlocked state by rotating. The locking component 6 can be switched back and forth between the locked state and the unlocked state by rotating the locking component 6 90° clockwise or counterclockwise. In the locked state, the locking component 6 can limit the rotation of the push rod 3, while keeping the push rod 3 in a state of engagement with the active pawl 13 and the non-return pawl 11. By repeatedly pulling the trigger 5, the tibial pad is pushed into the tibial tray in a step-by-step manner. In the unlocked state, the locking component 6 can release the restriction on the push rod 3. At this time, the user can rotate the push rod 3 to disengage the push rod 3 from the active pawl 13 and the non-return pawl 11, and can manually push the push rod 3 backward to remove the tibial tray from the device.

[0037] Figure 4 A top view of the device in an unlocked state in some embodiments is illustrated. Figure 5 for Figure 4 Partial cross-sectional view of section BB. Figure 5 A top view of the device in a locked state in some embodiments is shown. Figure 6 for Figure 5 Partial cross-sectional view of CC section. Please refer to Figure 2 The push rod 3 is a round rod, and in addition to the axially arranged ratchet teeth 14, its surface also has a flat section 30 extending along the axial direction. Figure 2 The locking component 6 includes a locking piece 26 located in the housing 1 and a rotating rod 27 located on the surface of the housing 1. One end of the locking piece 26 is connected to one end of the rotating rod 27 through a rotating pin 28. The locking component 6 is rotatably arranged on the housing 1. Specifically, the rotating pin 28 penetrates the wall of the housing 1 in a direction perpendicular to the plane 30 and can rotate relative to the housing 1 around the central axis of the rotating pin 28, so that the rotating movement of the rotating rod 27 can drive the locking piece 26 to rotate around the central axis of the rotating pin 28. Please continue to refer to Figure 2 and Figure 3 The locking piece 26 extends toward the plane section 30 along the direction of its rotation center axis, and the end of the locking piece 26 is close to the plane section 30 and forms an arc-shaped notch 29 facing the plane section 30 at the end. When the rotating rod 27 is rotated, the locking piece 26 rotates around the center axis perpendicular to the plane section 30 at a position opposite to the plane section 30 to keep the end of the locking piece 26 close to the plane section 30 for rotation. The inner wall of the arc-shaped notch 29 is a cylindrical surface, so the arc-shaped notch 29 defines a generatrix. By rotating the locking piece 26, the generatrix of the arc-shaped notch 29 can be switched between the two states of being parallel to the push rod 3 and being perpendicular to the push rod 3. Please refer to Figure 7The locking component 6 is constructed so that when the push rod 3 is respectively engaged with the active pawl 13 and the non-return pawl 11 and the locking plate 26 is rotated until the generatrix of the arc-shaped notch 29 is perpendicular to the axial direction of the push rod 3, the end plane portion of the locking plate 26 is completely opposite to the plane cut surface 30 and close to each other, and the push rod 3 is restricted from rotating by abutting against the plane cut surface 30, thereby keeping the push rod 3 in an engaged state with the active pawl 13 and the non-return pawl 11. Please refer to Figure 6 The locking component 6 is also constructed so that when the locking piece 26 is rotated until the generatrix of the arc-shaped notch 29 is parallel to the axial direction of the push rod 3, the arc-shaped notch 29 of the locking piece 26 is adapted to the circular outer contour of the push rod 3, and the end plane portion of the locking piece 26 is no longer opposite to the plane section 30. A gap is formed between the end of the locking piece 26 and the push rod 3 at each position, and the locking piece 26 is separated from the push rod 3 to release the rotation restriction on the push rod 3, so that the push rod 3 can rotate freely.

[0038] The locking component 6 is configured to rotate within an angle range of 0-90°, and the two extreme positions of rotation correspond to the locked state and the unlocked state, respectively. When locking and unlocking, the user only needs to rotate the locking component 6 to the extreme position, without having to determine whether the locking component 6 has been rotated into place based on the rotation angle. The device also includes a limiting portion 43, which is used to limit the rotation angle range of the locking component 6 to 0-90°. In the locked state, the generatrix of the arc-shaped notch 29 is perpendicular to the axial direction of the push rod 3; in the unlocked state, the generatrix of the arc-shaped notch 29 is parallel to the axial direction of the push rod 3. In other words, the locking plate 26 can be rotated 90° forwards and backwards to switch the locking component 6 between the locked state and the unlocked state. During the process of the locking plate 26 rotating 90°, the area swept by the locking plate 26 in space forms two quarter-cylindrical areas. Part or all of the limiting portion 43 is located in one of the quarter-cylindrical areas, and the side plane boundaries of the quarter-cylindrical areas are respectively aligned with the corresponding limiting portion surfaces. For example, please combine Figure 3 , Figure 5 and Figure 7 The limiting portion 43 is a cylindrical pin, one end of which is connected to the side plate 42 on the right side of the housing 1, and the other end extends to the left to a quarter cylindrical area, and the end of the cylindrical pin extends to a side plane boundary of the quarter cylindrical area, and the side wall of the cylindrical pin is tangent to the other side plane boundary of the quarter cylindrical area, so that the cylindrical shape can limit the rotation of the locking plate 26 within the range of 0-90°.

[0039] The rotating rod 27 extends in a direction perpendicular to the generatrix of the arc-shaped notch 29. The locking member 6 can be configured to be in an unlocked state when the rotating rod 27 is rotated to extend laterally, such as Figure 4 When the lever 27 is rotated 90° to extend backward, the locking member 6 is in a locked state, as shown Figure 6As shown. The arrangement of the locking member 6 is more in line with the operating habits of the doctor. Of course, the angle and extension direction of the rotating rod 27 in the locked state can also have other configurations.

[0040] For further information, please refer to Figure 2 The locking component 6 also includes an elastically retractable positioning pin 31, and a first positioning groove 32 and a second positioning groove 33 that can be concave-convexly matched with the telescopic end of the positioning pin 31 are also provided on the surface of the housing 1. The first positioning groove 32 and the second positioning groove 33 can be set to be concave-convex, so that the positioning pin 31 can leave the positioning groove when the locking component 6 is slightly rotated. The first positioning groove 32 corresponds to the locked state, and the second positioning groove 33 corresponds to the unlocked state. The positioning pin 31 and the rotating pin 28 are arranged at one end of the rotating rod 27 in parallel with each other. When the rotating rod 27 is rotated, the positioning pin 31 can rotate around the rotating pin 28. When the locking component 6 is rotated to the locked state, the positioning pin 31 just rotates to the first positioning groove 32; when the locking component 6 is rotated to the unlocked state, the positioning pin 31 just rotates to the second positioning groove 33. The positioning pin 31 can indicate whether the locking component 6 is rotated to the right position, and can keep the locking component 6 in the locked or unlocked state after it is in the right position.

[0041] exist Figure 3 In the embodiment, the active pawl 13 and the non-return pawl 11 are arranged below the push rod 3, the ratchet 14 and the planar cut surface 30 are arranged on opposite sides of the push rod 3, and the locking component 6 is arranged on the upper part of the housing 1. In some embodiments, the locking component 6 can also be arranged on the side of the housing 1, and the planar cut surface 30 is arranged at 90° relative to the ratchet 14.

[0042] The front surface of the pad 8 is opposite to the stopper 7, and the front surface is configured to be an arc shape that matches the rear edge of the tibial pad. Figure 1 and Figure 2 The cushion block 8 can be made of plastic and is clamped on a metal base 34, which is connected to the front end of the push rod 3. The metal base 34 is not completely rigidly connected to the push rod 3. For example, the metal base 34 is connected to the push rod 3 through a pin 35, so that the metal base 34 can be loosened within a small range.

[0043] Please refer to Figure 1The stop component 7 includes a first component 36 and a second component 37, wherein the first component 36 is made of metal and is integrated with the extension part 2. The second component 37 can be made of plastic and is arranged behind the first component 36, and the upper end of the second component 37 is rotatably connected to the extension part 2. A fixing pin 38 is provided on the rear side of the first component 36, and the fixing pin 38 passes through the second component 37 and a limiting protrusion 39 is provided at the free end of the fixing pin 38 to limit the second component 37 from being separated from the fixing pin 38. A return spring 40 is also provided between the first component 36 and the second component 37 and is sleeved on the fixing pin 38. The stop component 7 is used to stop the gasket. When the gasket is pushed in, the doctor can observe whether the gasket has been pushed in and the effect of the gasket pushing in can be observed.

[0044] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A knee joint prosthesis engaging device, characterized in that: include: A shell having a first accommodating cavity therein, and a first hole is respectively provided at the front end and the rear end of the shell; An extension portion extending distally from the housing, wherein a distal end of the extension portion forms a stop member downwardly; A push rod is arranged behind the stop member and passes through the first hole, a pad block opposite to the stop member is arranged at the far end of the push rod, and ratchet teeth are arranged along the axial direction of the push rod; A non-return pawl and a push block are arranged in the first accommodating chamber, the non-return pawl is fixed in position, the push block is sleeved on the push rod and can move forward and backward, an active pawl is arranged in the push block, and the ratchet teeth are respectively engaged with the active pawl and the non-return pawl; A grip disposed below the housing and a rotatable trigger, wherein the upper end of the trigger extends into the first accommodating cavity and engages with the push block to actuate the push block; as well as a locking component configured to restrict the rotation of the push rod and release the restriction on the rotation of the push rod, The push rod is a round rod and has a plane section extending along the axial direction of the push rod formed on its surface; the locking component comprises a locking plate located inside the housing and a rotating rod located outside the housing, one end of the locking plate is connected to the rotating rod through a rotating pin, the other end of the locking plate is close to the plane section, the rotating pin penetrates the wall of the housing in a direction perpendicular to the plane section and can rotate relative to the housing around the central axis of the rotating pin, and the end of the locking plate close to the plane section is provided with an arc-shaped notch facing the plane section; The stop component includes a first component and a second component, the second component is arranged behind the first component, the upper end of the second component is rotatably connected to the extension part, a fixing pin is provided on the rear side of the first component, the fixing pin passes through the second component and a limiting protrusion is provided at the free end of the fixing pin to limit the second component from detaching from the fixing pin, and a reset spring is also provided between the first component and the second component and is sleeved on the fixing pin.

2. The knee joint prosthesis engaging device according to claim 1, characterized in that: The non-return pawl is rotatably connected to the housing below the push rod, the pawl head of the non-return pawl is arranged forward relative to the pawl tail, the pawl tail of the non-return pawl is exerted with a forward force by the second spring, and in the locked state, the pawl head of the non-return pawl is engaged with the ratchet teeth; The active pawl is rotatably connected to the push block below the push rod, the pawl head of the active pawl is arranged forward relative to the pawl tail, the pawl tail of the active pawl is applied with a forward force by the first spring, and in the locked state, the pawl head of the active pawl is engaged with the ratchet.

3. The knee joint prosthesis engaging device according to claim 1, characterized in that: It also includes a limiting portion, at least part of which is located in a quarter-cylindrical area swept by the locking plate when it rotates 90° from a state where the generatrix of the arc-shaped notch is perpendicular to the push rod to a state where the generatrix of the arc-shaped notch is parallel to the push rod, and two side plane boundaries of the quarter-cylindrical area are respectively aligned with the corresponding surfaces of the limiting portion.

4. The knee joint prosthesis engaging device according to claim 1, characterized in that: The rotating rod has an elastically retractable positioning pin, and the surface of the housing has a first positioning groove and a second positioning groove that can be concave-convexly matched with the retractable end of the positioning pin; in a locked state, the positioning pin is matched with the first positioning groove; In the unlocked state, the positioning pin cooperates with the second positioning groove.

5. The knee joint prosthesis engaging device according to claim 1, characterized in that: The lower part of the trigger is provided with a torsion spring, which applies a forward force to the lower part of the trigger; the upper part of the trigger has a pair of trigger arms arranged at intervals, and the ends of the trigger arms are provided with notches, and the left and right sides of the push block are provided with pins, the push block is placed between the two trigger arms, and the pins are freely inserted into the notches corresponding to the trigger arms.

6. The knee joint prosthesis engaging device according to claim 1, characterized in that: The front surface of the pad is configured to be an arc shape matched with the rear edge of the tibial pad. The pad is made of plastic and is clamped on a metal base, which is connected to the front end of the push rod through a pin.

7. The knee joint prosthesis engaging device according to claim 3, characterized in that: The rotating rod extends along a generatrix direction perpendicular to the arc-shaped notch.

Images