Patella fixator used in knee arthroplasty

Abstract

The invention relates to the technical field of knee arthroplasty, and discloses a patella fixator used in knee arthroplasty, the patella fixator comprises a support rod, the surface of the support rod is provided with two fixing assemblies, each fixing assembly is composed of a lower fixing plate and an upper fixing plate chain, and the upper surface of each lower fixing plate is provided with a fixing bottom surface; a plurality of plate chain units are arranged in the upper fixing plate chain, the lower surface of each plate chain unit is a fixing face, and according to the patella fixator used in the knee joint replacement, the two fixing assemblies are arranged, and the upper fixing plate chain composed of the adapter, the connecting block, the plate chain assemblies and the tail plate is designed to be matched with the lower fixing plate, so that the knee joint replacement is facilitated, and the knee joint replacement efficiency is improved. By means of the design of the fixing guide seat, the rotating ring and the guide block, the fixing guide seat, the rotating ring and the guide block are matched with the tail plate and the plate chain assembly, the patella can be fixed, and meanwhile the plate chain unit making contact with the patella can conveniently apply acting force perpendicular to the fixing face of the patella to the patella.

Description

Technical Field

[0001] The invention relates to the technical field of knee replacement, in particular to a patella fixer used in knee replacement. Background Art

[0002] With the aging of the population, degenerative osteoarthritis of the knee is becoming more and more common. In addition, knee diseases such as rheumatoid arthritis and traumatic osteoarthritis often lead to serious knee lesions. Currently, knee replacement is the only means to treat advanced knee diseases. Knee replacement is to replace the damaged femoral and tibial cartilage with artificial prostheses.

[0003] In addition, after femoral tibia replacement, the patella often does not reach the degree of replacement, but the patella still needs to be trimmed to make it fit the replaced knee joint. Specifically, patella trimming requires the patella to be everted and then trimmed smooth with an electric saw to avoid collision between the patella and the knee prosthesis. In this process, there is no dedicated patella fixator. Two towel clamps are often used to fix the upper and lower sides of the patella during the patella trimming process. The surgeon holds the two crossed towel clamps with one hand and uses the other hand to hold the electric saw to trim the patella surface. In actual operation, it is difficult for the towel clamp to fit well with the patella, and it is difficult for the towel clamp to exert effective force according to the surface shape of the patella. Therefore, there will be some defects, including: the towel clamp will damage the normal soft tissue on both sides of the patella; for different types of patella, the fixing effect of the towel clamp is difficult to guarantee; the other hand and other tissues of the patient are easily injured during the trimming process with an electric saw; the scale of trimming is difficult to control, and the patellar surface is easily damaged by excessive sawing. Summary of the invention

[0004] In order to solve the problems that the towel clamps currently used may damage the normal soft tissues on both sides of the patella; the fixing effect of the towel clamps is difficult to ensure for different types of patella; the other hand and other tissues of the patient are easily injured during the trimming process with an electric saw; the trimming scale is difficult to control and the patella surface is easily damaged by excessive sawing, the present invention is achieved through the following technical solutions: a patella fixator used in knee replacement surgery, comprising a support rod, two groups of fixing components are arranged on the surface of the support rod, the fixing components are composed of a lower fixing plate and an upper fixing plate chain, and the upper surface of the lower fixing plate is provided with a fixing bottom surface;

[0005] The upper fixed plate chain is provided with a plurality of plate chain units, the lower surface of the plate chain unit is a fixed surface, and the fixed surface can be fitted with the surface of the patella by rotating the plate chain unit. The plurality of plate chain units in the two groups of fixed components cooperate with the corresponding fixed bottom surfaces to fix the patella.

[0006] Furthermore, the upper fixed plate chain is composed of an adapter, a connecting block, a plurality of plate chain units and a tail plate;

[0007] The lower fixing plate is axially slidably mounted on the surface of the support rod, and the adapter is rotatably mounted up and down at the connection between the lower fixing plate and the support rod;

[0008] The connecting block is connected to the adapter seat through a universal connector, one of the plate chain units is rotatably connected to a side end of the connecting block away from the adapter seat through a connecting rod, a plurality of plate chain units are rotatably connected in sequence through the connecting rod, and the tail plate is rotatably connected to the tail end plate chain unit of the plurality of plate chain units through the connecting rod;

[0009] The adapter seat, the connecting block, the plurality of plate chain units and the tail plate can all rotate up and down, and the connecting block can perform a circular rotation on the connecting end surface of the adapter seat through a universal connecting piece.

[0010] Furthermore, a fixed guide seat is slidably provided on the upper surface of the lower fixed plate, a swivel is rotatably installed inside the fixed guide seat, a guide block is radially slidably installed inside the swivel, the guide block is "mouth" shaped, and a spline is provided on the inner side of the guide block;

[0011] The side surfaces of the plate chain unit and the tail plate are both provided with connecting grooves, and the splines on the inner side surface of the guide block cooperate with the connecting grooves on the side surfaces of the tail plate and / or the plate chain unit;

[0012] A radial guide groove is provided on the surface of the rotating ring, the opening direction of the guide groove is the same as the sliding direction of the guide block, a cable is radially arranged inside the guide groove, and one end of the cable is fixedly connected to the guide block.

[0013] Furthermore, a connecting plate is slidably mounted on the inner surface of the lower fixed plate, the connecting plate is fixedly connected to the fixed guide seat, and a reel is rotatably mounted on the upper surface of the connecting plate;

[0014] A guide rod is fixedly arranged on the surface of the fixed guide seat. After the cable extends out of the guide groove, it goes around the guide rod and is wound on the surface of the drum.

[0015] Furthermore, an operating ring is fixedly installed on the surface of the swivel, and a plurality of limit slots are circumferentially distributed on the surface of the operating ring. Fixing holes are provided on the surfaces of the fixed guide seat corresponding to the operating ring, and a detachable pin is used to cooperate between the limit slots and the fixing holes to limit the rotation of the swivel.

[0016] Furthermore, the reel is rotatably mounted in a support on the upper surface of the connecting plate, an operating disk is fixedly mounted on one side of the reel, and a limiting pin is inserted on the surface of the operating disk;

[0017] A plurality of limiting holes are arranged on the circumference of the surface of the support corresponding to the operating panel, and the limiting pins are matched with the limiting holes.

[0018] Furthermore, the connection plates in the two groups of the fixing components are connected by an insertion rod, and the insertion rod is slidably inserted inside one of the connection plates.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The patella fixator used in knee replacement surgery can achieve close contact with the patella by setting two groups of fixing components and designing an upper fixing plate chain composed of an adapter, a connecting block, a plurality of plate chain components and a tail plate to cooperate with a lower fixing plate. The design of the fixing guide seat, the swivel and the guide block, and the cooperation with the tail plate and the plate chain component can achieve fixation of the patella and facilitate the plate chain unit in contact with the patella to apply a force perpendicular to its fixing surface to the patella. The patella fixing method can improve the fixation effect of the patella and avoid damage to normal soft tissues on both sides of the patella during fixation. In addition, effective fixation can be achieved for different types of patellas, thereby reducing the risk in the electric saw trimming process, reducing the difficulty of trimming, and improving the patella trimming effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a stereoscopic diagram of the overall structure of the patella fixator of the present invention;

[0022] Figure 2 It is a side view of the patella fixator structure of the present invention;

[0023] Figure 3 For the present invention Figure 2 A schematic diagram of the enlarged structure at A in the middle;

[0024] Figure 4 It is a stereoscopic diagram of the related structures of the lower fixing plate, the upper fixing plate chain and the fixing guide seat on one side of the patella fixator of the present invention;

[0025] Figure 5 This is a three-dimensional diagram of the fixed guide seat structure of the present invention;

[0026] Figure 6 This is a three-dimensional diagram of the structure of the universal connector of the present invention;

[0027] Figure 7 This is a three-dimensional diagram of the connecting rod structure of the present invention;

[0028] Figure 8 It is a schematic diagram of the force exerted on the patella by the lower fixing plate and the upper fixing plate chain of the present invention.

[0029] In the figure: 1. support rod; 2. lower fixed plate; 201. fixed bottom surface; 3. adapter seat; 301. connecting block; 302. plate chain unit; 303. tail plate; 304. connecting groove; 4. universal connector; 5. connecting rod; 6. fixed guide seat; 601. fixing hole; 7. swivel; 701. operating ring; 8. guide block; 9. guide rod; 10. cable; 11. spring member; 12. connecting plate; 13. reel; 14. operating panel; 141. limit pin; 15. plug rod. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The embodiment of the patella fixator used in the knee replacement surgery is as follows:

[0032] See also Figure 1-Figure 8 A patellar fixator used in knee replacement surgery includes a support rod 1, two sets of fixing components are arranged on the surface of the support rod 1, and the two sets of fixing components cooperate to fix the patella, and the fixing components are composed of a lower fixing plate 2 and an upper fixing plate chain, and the upper surface of the lower fixing plate 2 is provided with a fixing bottom surface 201;

[0033] Several plate chain units 302 are arranged in the upper fixed plate chain, and the lower surface of the plate chain unit 302 is the fixed surface. By rotating the plate chain unit 302, the fixed surface can be fitted with the surface of the patella. Several plate chain units 302 in the two groups of fixed components cooperate with the corresponding fixed bottom surface 201 to fix the patella. The design of several plate chain units 302 in the upper fixed plate chain can increase the effective contact surface between the upper fixed plate chain and the patella, and improve the fixing effect of the fixed component on the patella. The contact surfaces of the plate chain unit 302 and the fixed bottom surface 201 with the patella are both frosted surfaces, which are used to increase the friction resistance when the plate chain unit 302 and the fixed bottom surface 201 contact the patella, and at the same time will not damage the local tissue of the patella.

[0034] It should be noted that the upper fixed plate chain is composed of an adapter seat 3, a connecting block 301, several plate chain units 302 and a tail plate 303; the lower fixed plate 2 is axially slidably installed on the surface of the support rod 1, and the adapter seat 3 is installed at the connection between the lower fixed plate 2 and the support rod 1 for vertical rotation.

[0035] The connecting block 301 is connected to the adapter seat 3 through a universal connector 4, one of the plate chain units 302 is rotatably connected to one side end of the connecting block 301 away from the adapter seat 3 through a connecting rod 5, and several plate chain units 302 are rotatably connected in sequence through the connecting rod 5. The tail plate 303 is rotatably connected to the plate chain unit 302 at the tail end of the several plate chain units 302 through the connecting rod 5, and the plate body composed of the connecting block 301, several plate chain units 302 and the tail plate 303 corresponds to the fixed bottom surface 201.

[0036] The adapter 3, the connecting block 301, the plurality of plate chain units 302 and the tail plate 303 can all rotate up and down. The connecting block 301 can make a circular rotation on the connecting end surface of the adapter 3 through the universal connector 4. The connecting block 301 and the plurality of plate chain units 302 can rotate up and down between adjacent ones, which is convenient for the plate chain unit 302 to contact the surface of the patella. The connecting block 301 can make a circular rotation, which will drive the plurality of plate chain units 302 to rotate together, so as to facilitate the plate chain unit 302 to fit the surface of the patella, that is, the fixing surface of the plate chain unit 302 can be tangent to the curved surface of the patella surface, which is beneficial to improve the fixing effect of the fixing assembly on the patella.

[0037] On this basis, a fixed guide seat 6 is slidably provided on the upper surface of the lower fixed plate 2, a swivel 7 is rotatably installed inside the fixed guide seat 6, an operating ring 701 is fixedly installed on the surface of the swivel 7, a plurality of limit slots are circumferentially distributed on the surface of the operating ring 701, a fixing hole 601 is provided on the surface corresponding to the fixed guide seat 6 and the operating ring 701, a detachable pin is used to make the limit slot cooperate with the fixing hole 601 to limit the rotation of the swivel 7, the rotation of the swivel 7 can be controlled by the operating ring 701, and when the pin cooperates with the limit slot and the fixing hole 601, the rotation of the swivel 7 is limited.

[0038] A guide block 8 is radially slidably installed inside the swivel 7. A spring member 11 is provided between the guide block 8 and the swivel 7 for resetting the guide block 8. The guide block 8 is in a "mouth" shape, and a spline is provided on the inner side of the guide block 8. The side surfaces of the plate chain unit 302 and the tail plate 303 are both provided with connecting grooves 304. The splines on the inner side of the guide block 8 cooperate with the connecting grooves 304 on the side surfaces of the tail plate 303 and / or the plate chain unit 302. When the tail plate 303 and / or the plate chain unit 302 cooperate with the guide block 8, the swivel 7 can be driven to rotate. The tail plate 303, the plate chain unit 302 and the connecting block 301 rotate together until the fixing surface of the plate chain unit 302 can fit with the surface of the patella. At this position, the rotation of the swivel 7 is restricted, thereby restricting the rotation of the plate chain unit 302. By adjusting the position of the fixed guide seat 6, the plate chain unit 302 can be initially fitted and fixed on the surface of the patella. The fixing method of the fixed guide seat 6 on the surface of the lower fixed plate 2 adopts the existing fixing method, such as the combination of holes and pins or bolts, which will not be described in detail here.

[0039] A radial guide groove is provided on the surface of the swivel 7, and the opening direction of the guide groove is the same as the sliding direction of the guide block 8. A cable 10 is radially arranged inside the guide groove, and one end of the cable 10 is fixedly connected to the guide block 8. When the cable 10 is tightened, the cable 10 will generate a radial tension on the guide block 8, and the guide block 8 will simultaneously generate a radial tension on the tail plate 303 and / or the corresponding plate chain unit 302, so that the force exerted on the patella by the plate chain unit 302 that is in contact with the patella is perpendicular to the fixed surface of the plate chain unit 302, that is, Figure 8 In the figure, F0, the force applied by the fixed bottom surface 202 to the patella is F, thereby improving the effect of the plate chain unit 302 applying a fixing force to the patella, improving the fixation effect of the patella, and at the same time avoiding the sliding of the plate chain unit 302 on the surface of the patella, reducing damage to the surface tissue of the patella.

[0040] On this basis, a connecting plate 12 is slidably installed on the inner surface of the lower fixed plate 2, and the connecting plate 12 is fixedly connected to the fixed guide seat 6. A reel 13 is rotatably installed on the upper surface of the connecting plate 12, and the reel 13 is rotatably installed in a support on the upper surface of the connecting plate 12.

[0041] An operating disk 14 is fixedly installed on one side of the reel 13, and a limit pin 141 is inserted into the surface of the operating disk 14; a plurality of limit holes are distributed circumferentially on the surface of the support corresponding to the operating disk 14, and the limit pin 141 is adapted to the limit hole, and the limit pin 141 cooperates with the limit hole to limit the rotation of the operating disk 14, thereby limiting the rotation of the reel 13.

[0042] A guide rod 9 is fixedly provided on the surface of the fixed guide seat 6. After the cable 10 extends out of the guide groove, it bypasses the guide rod 9 and is wound on the surface of the drum 13. The drum 13 is rotated by the operating disk 14, so that the cable 10 can be wound on the surface of the drum 13, and then the cable 10 is used to apply tension to the guide block 8.

[0043] It should also be noted that the connecting plates 12 in the two sets of fixing components are connected by an insert rod 15, and the insert rod 15 is slidably inserted into the inside of one of the connecting plates 12. The fixing method between the insert rod 15 and the connecting plate 12 adopts the existing fixing method, for example, it can be fixed by the combination of holes and pins or bolts, which will not be described in detail here. The design of the insert rod 15 can be coordinated with the support rod 1 to adjust the distance between the two sets of fixing components, so as to facilitate the fixation of patellae of different sizes.

[0044] The working principle of the patellar fixator:

[0045] First, push the fixed guide seat 6 toward the adapter seat 3 so that the plate body composed of the connecting block 301 and a plurality of plate chain units 302 can arch upward to form an arch shape so that the turned-out patella can be placed therein, and then adjust the distance between the two sets of fixing components to a suitable position according to the size of the patella.

[0046] Adjust the position of the fixed guide seat 6, and adjust the tail plate 303 and the plate chain unit 302 to the appropriate position inside the guide block 8, and cooperate with the rotating ring 7 so that the plate chain unit 302 can fit on the surface of the patella, and at the same time, the plate body formed between several plate chain units 302 is not loose.

[0047] Then, the drum 13 is rotated by the operating disk 14, and the cable 10 is tightened by the drum 13, so that the cable 10 generates radial tension on the guide block 8, so that the guide block 8 generates radial force on the plate chain unit 302 inside it to further fix the patella. The two sets of fixing components cooperate to fix the patella.

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A patellar fixator for use in knee replacement surgery, comprising a support rod (1), wherein two sets of fixing components are arranged on the surface of the support rod (1), characterized in that: The fixing assembly is composed of a lower fixing plate (2) and an upper fixing plate chain, and the upper surface of the lower fixing plate (2) is provided with a fixing bottom surface (201); A plurality of plate chain units (302) are arranged in the upper fixed plate chain, and the lower surface of the plate chain unit (302) is a fixed surface. By rotating the plate chain unit (302), the fixed surface can be fitted with the surface of the patella. The plurality of plate chain units (302) in the two groups of fixed components cooperate with the corresponding fixed bottom surfaces (201) to fix the patella.

2. The patella fixator used in knee replacement surgery according to claim 1, characterized in that: The upper fixed plate chain is composed of an adapter seat (3), a connecting block (301), a plurality of plate chain units (302) and a tail plate (303); The lower fixing plate (2) is axially slidably mounted on the surface of the support rod (1), and the adapter seat (3) is rotatably mounted at the connection between the lower fixing plate (2) and the support rod (1); The connecting block (301) is connected to the adapter seat (3) via a universal connecting piece (4); one of the plate chain units (302) is rotatably connected to a side end of the connecting block (301) away from the adapter seat (3) via a connecting rod (5); a plurality of plate chain units (302) are rotatably connected in sequence via the connecting rod (5); and the tail plate (303) is rotatably connected to the tail end plate chain unit (302) of the plurality of plate chain units (302) via the connecting rod (5); The adapter seat (3), the connecting block (301), the plurality of plate chain units (302) and the tail plate (303) can all rotate up and down, and the connecting block (301) can rotate in a circle on the connecting end surface of the adapter seat (3) via a universal connecting piece (4).

3. The patella fixator used in knee replacement surgery according to claim 2, characterized in that: A fixed guide seat (6) is slidably provided on the upper surface of the lower fixed plate (2), a rotating ring (7) is rotatably installed inside the fixed guide seat (6), a guide block (8) is radially slidably installed inside the rotating ring (7), the guide block (8) is "mouth" shaped, and a spline is provided on the inner side surface of the guide block (8); The side surfaces of the plate chain unit (302) and the tail plate (303) are both provided with connection grooves (304), and the splines on the inner side surface of the guide block (8) cooperate with the connection grooves (304) on the side surfaces of the tail plate (303) and / or the plate chain unit (302); A radial guide groove is provided on the surface of the rotating ring (7), the opening direction of the guide groove being the same as the sliding direction of the guide block (8), a cable (10) is radially arranged inside the guide groove, and one end of the cable (10) is fixedly connected to the guide block (8).

4. The patella fixator used in knee replacement surgery according to claim 3, characterized in that: A connecting plate (12) is slidably mounted on the inner surface of the lower fixed plate (2), the connecting plate (12) is fixedly connected to the fixed guide seat (6), and a reel (13) is rotatably mounted on the upper surface of the connecting plate (12); A guide rod (9) is fixedly arranged on the surface of the fixed guide seat (6); after the pull cable (10) extends out of the guide groove, it bypasses the guide rod (9) and is wound on the surface of the reel (13).

5. The patella fixator used in knee replacement surgery according to claim 3 or 4, characterized in that: An operating ring (701) is fixedly mounted on the surface of the rotating ring (7); a plurality of limit slots are circumferentially arranged on the surface of the operating ring (701); a fixing hole (601) is provided on the surface of the fixed guide seat (6) corresponding to the operating ring (701); a detachable latch is used to make the limit slot cooperate with the fixing hole (601) to limit the rotation of the rotating ring (7).

6. The patella fixator used in knee replacement surgery according to claim 4, characterized in that: The reel (13) is rotatably mounted in a support on the upper surface of the connecting plate (12); an operating disk (14) is fixedly mounted on one side of the reel (13); a limiting pin (141) is inserted into the surface of the operating disk (14); A plurality of limiting holes are provided on the circumference of the surface corresponding to the support and the operating panel (14), and the limiting pins (141) are adapted to the limiting holes.

7. The patella fixator used in knee replacement surgery according to claim 4, characterized in that: The connecting plates (12) in the two groups of the fixing components are connected via an insertion rod (15), and the insertion rod (15) is slidably inserted into the interior of one of the connecting plates (12).

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