A device capable of accelerating the establishment of a rabbit patellar subluxation malformation model

Abstract

The present invention relates to the technical field of orthopedic research models, specifically a device that can accelerate the establishment of a rabbit patellar subluxation malnutrition model, including a base and a leg rest board vertically arranged at the rear end of the top surface thereof, a support block hingedly connected to the middle of the front side of the leg rest board, a pair of lifting screws installed between the support block and the base, an accelerating softening mechanism arranged just above the support block, and a reciprocating pushing mechanism fixed to the rear half of the accelerating softening mechanism and located on the rear side of the leg rest board. After the present invention fixes a rabbit in supine position on the support block and the leg rest board, a servo motor drives the accelerating softening mechanism to reciprocately press the rabbit's patella to cause it to wear, and a motor drives the circular wheel to rotate and drive the accelerating softening mechanism to reciprocate up and down, so that the rabbit's patella wears faster, thereby simulating the movement trajectory of the patella, saving the labor cost of driving the animal, and further shortening the research cycle, and providing an animal model for related research on patellar malnutrition disease.

Description

Technical Field

[0001] The invention relates to the technical field of orthopedic research models, in particular to a device capable of accelerating the establishment of a rabbit patellar subluxation malformation model. Background Art

[0002] Chondromalacia Patellae (CMP), full name chondromalacia patellae, is a degenerative change of the patellar cartilage articular surface caused by long-term chronic wear of the patellofemoral joint cartilage. The articular cartilage will soften, crack, and delaminate. Damage to the subpatellar cartilage can be caused by knee trauma or strain. It is a degenerative disease that can cause chronic pain in the knee joint. In my country, the incidence rate is as high as 36.2%, and it is more common in women. The pathogenesis of CMP is currently unclear. Patellar subluxation is considered to be one of the causes of CMP.

[0003] Patellar softening can affect the knee joint, seriously affecting the movement function, and can cause complications such as traumatic arthritis and meniscus injury, causing great inconvenience to life and work. The cause of patellar softening is that there is a problem with the movement track of the patella, the patellar cartilage is worn, the friction between bones increases, and the disorder of biomechanics leads to cartilage damage. Pain, limited movement, etc. occur.

[0004] Currently, there are few studies on the establishment of CMP animal models, and the modeling time is long. This patent designs a pressing wear device that can accelerate the wear and softening of the patella after surgery through patellar subluxation surgery on rabbits. This device is fixed on the rabbit patella and set a programmed mode to adjust the time and force of pressing the patella. The force form is pressing, sliding up and down, and pressing and sliding alternately, which accelerates the damage of the patellar cartilage, shortens the modeling time and accelerates the degree of damage.

[0005] With regard to the establishment of a rabbit patellar softening model, the present invention uses patellar subluxation as a cause or starting point to create an animal model of patellar softening, which can provide an animal model basis for studying patellar softening-related diseases that are relatively difficult to treat in current medicine. Currently, there is no design for a device to accelerate patellar wear.

[0006] The existing rabbit patellar subluxation softening model is established by driving the animal to force the knee joint to move for 60 minutes three times a day after surgical operation to patellar subluxation, and the modeling time is 8 weeks. The device of this patent can be fixed on the patella, programmed to press and wear the patella, and can simulate the movement trajectory of the patella in forced movement, so that the patella slides up and down in the joint cavity, and then applies pressing force, which can speed up the modeling time and save the manpower cost of driving the animal. You only need to set the daily exercise time and number on the device, then select the force mode, and enter the pressure module. The modeling cycle can be shortened to accelerate patellar wear. Summary of the invention

[0007] The purpose of the present invention is to provide a device that can accelerate the establishment of a rabbit patellar subluxation malformation model to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A device capable of accelerating the establishment of a rabbit patellar subluxation malnutrition model comprises a base (1) and a leg rest plate (10) vertically arranged at the rear end of its top surface and an accelerated softening mechanism (2); the leg rest plate (10) is used to fix the rabbit's legs, and the accelerated softening mechanism (2) is used to accelerate the softening of the rabbit's patella.

[0010] The top side of the legrest board (10) is symmetrically provided with a slide groove (11), the middle part of the front side of the legrest board (10) is laterally provided with a fixing sleeve (13), one side of the fixing sleeve (13) is hinged with a support block (12) through a pin, a pair of lifting screws (15) are installed between the support block (12) and the base (1), an acceleration softening mechanism (2) is arranged directly above the support block (12), and a reciprocating pushing mechanism (4) is fixed to the rear half of the acceleration softening mechanism (2) and located on the rear side of the legrest board (10).

[0011] Preferably, double rings are symmetrically provided on the bottom surface of the bottom end of the support block and the top surface at the front end of the base, a through hole is opened at one end of the lifting screw, the through hole is connected to the double rings by a pin, a rotating frame is connected between the two lifting screws, the rotating frame is a square frame structure and a ring is connected to the middle of the upper and lower ends, and the ring is threadedly connected to the lifting screw.

[0012] Preferably, fixing blocks are bonded to both sides of the middle of the support block, and a square notch is opened on the top side of the fixing block and is fastened with a strap.

[0013] Preferably, the front side of the pressure plate is symmetrically provided with circular holes with internal threads, the outer side of the adjustable distance handle is provided with threads and is threadedly connected to the circular holes of the pressure plate, and the rear end of the adjustable distance handle is bonded with a pushing head made of silicone.

[0014] Preferably, a T-shaped through groove is provided at the top of the track, and the size of the rear end of the slide is adapted to the size of the through groove of the track.

[0015] Preferably, a motor is coaxially connected to the central axis of the circular wheel, and the motor is fixedly connected to the legrest board.

[0016] A method for accelerating the establishment of a rabbit patellar subluxation malformation model comprises the following steps:

[0017] Step 1. Animal selection:

[0018] Select New Zealand rabbits, weighing about 2.5kg ± 0.3kg, of either sex;

[0019] Step 2: The New Zealand rabbits were generally anesthetized by injecting 3% pentobarbital solution into the ear vein at a dose of 1.0 mL / kg, and the rabbits were fixed on the operating table in a supine position;

[0020] Step 3: First, clean the area around the knees with 75% ethanol, remove the hair around the knee joints, then clean with 75% alcohol, disinfect with iodine 3 times, and lay a sterile sheet;

[0021] Step 4: Use a scalpel to make a 3-5 cm incision in the middle of the knee joint, cut the skin tissue layer by layer, and fully expose the patellofemoral joint;

[0022] Step 5: Make a 1-2.5 cm long incision on the inner and outer edges of the patella, cut the inner and outer joint capsules, push the patella outward, and make it in a state of patellar subluxation. Use sutures to overlap the outer joint capsule to ensure that the patella will not return to its original position spontaneously after the patellar subluxation surgery.

[0023] Step 6: Manually move the knee joint to observe the movement trajectory of the patella, and ensure that the patella is in a state of outward displacement, lateral tilt, and subluxation. Rinse the wound with iodine and suture the skin.

[0024] Step 7: Perform a CT scan of the knee joint after surgery to determine the position of the patella and the angle of patella tilt;

[0025] Step 8: One day before and on the day of surgery, 300,000 units of penicillin are injected intramuscularly to prevent infection. After surgery, 300,000 units of penicillin are injected intramuscularly for 3 consecutive days to prevent postoperative infection.

[0026] Step 9: 3 days after intramuscular injection of penicillin, the rabbits were equipped with a patellar pressing device and a pressing program was set to accelerate the massage of the cartilage on the contact surface;

[0027] Step 10. Put the two rings of the device on the upper and lower joints of the patella of the rabbit's hind legs 3 days after surgery, adjust the tightness and fix it. There are hanging rings on both sides of the rings. Hang the upper and lower hooks of the pressing module on the hanging rings. Fix the pressing module on the patella in a horizontal circle. Adjust the position of the module to fit closely to the semi-luxated patella. Adjust the control interface on the module to set the pressing time and interval.

[0028] The pressing time and interval set in step 10 are: 6 hours interval, 1 hour pressing. There are three optional force modes: vertical pressing, up and down sliding, and mixed force application.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The invention can replace the normal patellar wear of rabbits and accelerate the establishment of patellar softening model.

[0031] The device for accelerating the establishment of a patellar softening model of the present invention applies a certain force: pressing force, up and down sliding force or mixed force to promote cartilage damage on the patella. The time setting can be adjusted, and programmed forced exercise causes the patella to wear, replacing the daily human driving of animals, saving labor costs. The experimental animals involved in the present invention can also be other experimental animals, and the device can be adjusted according to the size of the animal. The present invention accelerates the modeling time and saves the labor time cost of driving animals for forced exercise.

[0032] The present invention designs a pressing wear device that can accelerate the postoperative wear and softening of the patella by performing patellar subluxation surgery on rabbits. The device is fixed on the patella of the rabbit, and a programmed mode is set to adjust the time and force of pressing the patella. The force forms are pressing, sliding up and down, and pressing and sliding alternately, which accelerates the damage of the patellar cartilage and shortens the modeling time and the degree of damage.

[0033] The device of the present invention can accelerate the establishment of a rabbit patellar subluxation malnutrition model. After the rabbit is fixed on the support block and the leg rest board in a supine position, the servo motor drives the accelerated softening mechanism to reciprocately press the rabbit's patella to cause it to wear. The motor drives the circular wheel to rotate and drives the accelerated softening mechanism to reciprocate up and down, so that the rabbit's patella wears faster, thereby simulating the movement trajectory of the patella in forced motion, and making the patella slide up and down in the joint cavity, which can save the manpower cost and time of driving the animal, improve efficiency, and further shorten the research cycle, providing an animal model for related research on patellar malnutrition disease and providing an animal model basis for treating diseases related to patellar malnutrition. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 It is an overall side view of the present invention;

[0036] Figure 3 This is a perspective view of the overall rear side of the present invention;

[0037] Figure 4 This is a schematic diagram of the base assembly structure of the present invention;

[0038] Figure 5 It is a schematic diagram of the assembly structure of the accelerated softening mechanism and the reciprocating pushing mechanism of the present invention;

[0039] Figure 6 This is a schematic diagram of the assembly structure of the lifting screw and the rotating frame of the present invention;

[0040] Figure 7 It is a schematic diagram of another overall structural form of the present invention.

[0041] Figure 8It is a schematic diagram of the connection structure between the slide and the connecting rod of the present invention.

[0042] The meanings of the symbols in the figure are:

[0043] 1. Base; 10. Leg support plate; 11. Slide; 12. Support block; 13. Fixed sleeve; 14. Double ring; 15. Lifting screw; 150. Through hole; 16. Rotating frame; 160. Ring; 17. Fixed block; 18. Band; 2. Acceleration softening mechanism; 20. Pressing plate; 21. Fixed column; 22. Fixed frame; 23. Support plate; 24. Bearing seat; 3. Adjustable distance handle; 30. Pushing head; 4. Reciprocating pushing mechanism; 40. Slide; 41. Track; 42. Connecting rod; 43. Round wheel; 5. Servo motor; 50. Screw; 51. Sliding block; 52. Connecting column; 6. Motor; 7. Leg support plate. DETAILED DESCRIPTION

[0044] 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.

[0045] In the description of the present invention, it should be understood that the terms "length", "width", "thickness", "depth", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, in the description of the present invention, "several" means two or more, unless otherwise clearly and specifically defined.

[0046] Example 1

[0047] See also Figure 1-Figure 8 , the present invention provides a technical solution:

[0048] A device for accelerating the establishment of a rabbit patellar subluxation malnutrition model comprises a base 1 and a leg rest plate 10 vertically arranged at the rear end of its top surface, and a slide groove 11 is symmetrically provided on the top side of the leg rest plate 10. A fixing sleeve 13 is horizontally arranged in the middle of the front side of the leg rest plate 10, which is a circular ring structure, and a support block 12 is hinged on one side of the fixing sleeve 13 through a pin, and a through hole is provided at the top of the support block 12 for inserting the pin, so that the support block 12 can rotate outside the fixing sleeve 13. A pair of lifting screws 15 are installed between the support block 12 and the base 1, which are used to adjust the lifting and lowering of the bottom end position of the support block 12. An accelerated softening mechanism 2 is arranged directly above the support block 12, which is used to press the subluxed patella of the rabbit leg. A reciprocating pushing mechanism 4 is fixed to the rear half of the accelerated softening mechanism 2 and located on the rear side of the leg rest plate 10, which can drive the accelerated softening mechanism 2 to press back and forth. The accelerated softening mechanism 2 includes a square pressure plate 20, and the inside of the pressure plate 20 is symmetrically connected with a distance adjustment handle 3. Fixed columns 21 are fixed at the corners of the pressure plate 20, and each upper and lower fixed columns 21 pass through a slide slot 11. A fixed frame 22 is fixed to the rear end of the fixed column 21, and a support plate 23 is slidably connected to the inner side surface of the bottom of the fixed frame 22. A bearing seat 24 is fixed to the top surface of the rear end of the support plate 23, and the two are fixedly connected. A bearing is embedded in the center hole of the bearing seat 24. The reciprocating pushing mechanism 4 includes a track 41 fixed to the rear side of the leg support plate 10, and a slide 40 is slidably connected to the inside of the track 41. The slide 40 is connected to the front end of the support plate 23 near the bottom, that is, the slide 40 slides up and down and moves synchronously with the support plate 23. A concave hole 44 is opened at the outer corner of the bottom end of the slide 40, and a connecting rod 42 is hinged in the concave hole 44 through a pin 45, and a round hole is opened on one side of the top of the connecting rod 42. The bottom end of the connecting rod 42 is connected with a rotatable round wheel 43, and a boss is provided on the end face of the round wheel 43 near the edge, and the boss is sleeved with a round hole provided on the side of the bottom end of the connecting rod 42. Since the boss deviates from the center of the round wheel 43, when the round wheel 43 rotates, the boss brings the connecting rod 42 to push the slide 40 to make up and down reciprocating motion on the track 41. The front end top surface of the support plate 23 is fixed with a servo motor 5, which is an existing conventional technology and will not be repeated in the present invention. The servo motor 5 sends a forward and reverse pulse command to the servo motor 5 to switch between forward and reverse rotation through a servo controller used in conjunction. One end of the output shaft of the servo motor 5 is coaxially connected with a screw rod 50, and the outer end of the screw rod 50 is plugged and matched with the bearing in the bearing seat 24. The outer side of the screw rod 50 is threadedly connected with a slider 51, and the inner side of the slider 51 is provided with a thread, so that when the screw rod 50 rotates, the slider 51 performs linear motion due to the limit of the support plate 23. The top of the slider 51 is connected to a connecting column 52, and the top of the connecting column 52 is fixedly connected to the fixed frame 22. The linear motion of the slider 51 drives the fixed frame 22 to reciprocate linearly, so that the distance adjustment handle 3 on the pressure plate 2 can squeeze the rabbit leg knee on the leg support plate 10 for pressing.

[0049] In this embodiment, the base 1 and the legrest board 10 are made of PP material to form an integral structure, and the support block 12 is made of PP material to form an integral structure, which is light in weight, good in toughness and strong in strength, and can make it durable.

[0050] Furthermore, the bottom surface of the bottom end of the support block 12 and the top surface of the front end of the base 1 are symmetrically provided with double rings 14, and a through hole 150 is opened at one end of the lifting screw 15. The through hole 150 and the double ring 14 are connected by a pin so that the two can rotate. A rotating frame 16 is connected between the two lifting screws 15. The rotating frame 16 is a square frame structure and a collar 160 is connected to the middle of the upper and lower ends. The collar 160 is provided with a thread. The external threads of the two lifting screws 15 are reverse threads. The collar 160 is threadedly connected to the lifting screws 15. When the rotating frame 16 is rotated forward and backward, the two lifting screws 15 can be moved away or closer, so that the tilt angle of the support block 12 can be adjusted to adjust the angle between the rabbit's body and its legs.

[0051] Specifically, a fixing block 17 is bonded to both sides of the middle of the support block 12. A square notch is provided on the top side of the fixing block 17 and a strap 18 is fastened to the rabbit body. The two straps 18 are fastened to each other to tighten the rabbit body. A pair of fixing blocks 17 are bonded to the front side of the leg plate 10 and located above and below the accelerated softening mechanism 2, so that the straps 18 are fastened to tighten the rabbit's thigh and calf, so that the rabbit is fixed as a whole, which is conducive to the wear and softening of the patella of its knee, so as to study

[0052] Specifically, the front side of the pressure plate 20 is symmetrically provided with a circular hole with an internal thread, the outer side of the distance adjustment handle 3 is provided with a thread and is threadedly connected to the circular hole of the pressure plate 20, and the rear end of the distance adjustment handle 3 is bonded with a push head 30 made of silicone material, which is in an arc Y shape and is conducive to pressing against the patella. By rotating the distance adjustment handle 3, the push head 30 presses the patella of the rabbit's knee to wear and soften it.

[0053] In addition, a T-shaped through slot is formed at the top of the track 41 , and the rear end size of the slide 40 matches the size of the through slot of the track 41 , so that the slide 40 can slide on the track 41 without slipping off.

[0054] It should be added that a motor 6 is coaxially connected to the central axis of the round wheel 43, and the round wheel 43 is driven to rotate by the motor 6 to drive the slide 40 to reciprocate up and down. The motor 6 is fixedly connected to the leg rest plate 10.

[0055] Before using the device for accelerating the establishment of a rabbit patellar subluxation malnutrition model, the rabbit's patella is surgically placed in a subluxation state and allowed to recover for 3 days. The experimental rabbit is then placed supinely on a support block 12 after general anesthesia, with its legs resting on a leg support board 10. All straps 18 are then tightened to stabilize the rabbit. The adjustable distance handle 3 is rotated to press the push head against the patella of the rabbit's knee. The servo motor 5 and the servo controller are powered on to work. The servo controller sends forward and reverse pulses to control the servo motor 5 to rotate forward and reverse, thereby By rotating the screw rod 50 forward and reverse, the slider 51 and the accelerated softening mechanism 2 can be driven to reciprocate horizontally as a whole, so that the push head 30 continuously and repeatedly presses the patella, and then the power of the motor 6 is turned on to make it work, driving the round wheel 43 to rotate, and driving the slide 40 to reciprocate up and down in the track 41 with the connecting rod 42, and driving the accelerated softening mechanism 2 to move up and down as a whole, so that the push head 30 continuously and softly presses the patella up and down. This device can replace the normal movement of the rabbit's patella wear and accelerate the establishment of a patellar softening model for research.

[0056] Example 2

[0057] As the second technical solution of the present invention, please refer to Figure 7 :

[0058] A device for accelerating the establishment of a rabbit patellar subluxation malnutrition model comprises a base 1 and a leg support plate 7 vertically arranged at the rear end of its top surface, the upper half of the leg support plate 7 is separated from the middle to form two strip plates, so that the rabbit's legs can be placed separately. The front side surfaces of the two strip plates are symmetrically provided with slide grooves 11. A fixing sleeve 13 is horizontally arranged at the lower middle part of the front side surface of the leg support plate 7, which is a circular ring structure, and a support block 12 is hinged on one side of the fixing sleeve 13 through a pin, which is used to support the rabbit lying on its back. A lifting screw 15 of the same structure is also installed between the support block 12 and the base 1. A pressing structure 2, a distance adjustment handle 3 and a reciprocating pushing mechanism 4 of the same structure as that of the embodiment 1 and reduced in size are installed on the top of the leg support plate 7, and a reduced version of the servo motor 5 and the motor 6 installed on the reciprocating pushing mechanism 4, whose movement mode and principle are the same as the working principle of the embodiment 1, and the device is convenient for separating the rabbit's legs separately to perform patellar malnutrition operation.

[0059] Example 3

[0060] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A device for accelerating the establishment of a rabbit patellar subluxation malformation model, characterized in that: It comprises a base (1) and a leg rest plate (10) and an accelerated softening mechanism (2) vertically arranged at the rear end of its top surface, wherein the leg rest plate (10) is used to fix the legs of the rabbit, and the accelerated softening mechanism (2) is used to accelerate the softening of the patella of the rabbit; The top side of the legrest board (10) is symmetrically provided with a slide groove (11), the middle part of the front side of the legrest board (10) is laterally provided with a fixing sleeve (13), one side of the fixing sleeve (13) is hinged with a support block (12) through a pin, a pair of lifting screws (15) are installed between the support block (12) and the base (1), an acceleration softening mechanism (2) is arranged directly above the support block (12), and a reciprocating pushing mechanism (4) is fixed to the rear half of the acceleration softening mechanism (2) and located on the rear side of the legrest board (10); The accelerated softening mechanism (2) comprises a square pressure plate (20), the interior of the pressure plate (20) is symmetrically connected to a distance adjusting handle (3), the corners of the pressure plate (20) are fixed with fixed columns (21), each of the upper and lower fixed columns (21) passes through a slide groove (11), the rear end of the fixed column (21) is fixed with a fixed frame (22), the inner side surface of the bottom of the fixed frame (22) is slidably connected with a support plate (23), and the top surface of the rear end of the support plate (23) is fixed with a bearing seat (24), The reciprocating pushing mechanism (4) comprises a track (41) fixed on the rear side of the legrest board (10), a slide table (40) is slidably connected inside the track (41), the slide table (40) is connected to the front end of the support plate (23) near the bottom, a concave hole (44) is opened at the outer corner of the bottom end of the slide table (40), and a connecting rod (42) is hinged in the concave hole (44), the bottom end of the connecting rod (42) is connected to a rotatable round wheel (43), the end surface of the round wheel (43) and near the edge are provided with a convex column, and the convex column is sleeved with a round hole opened on the side of the bottom end of the connecting rod (42), a servo motor (5) is fixed to the top surface of the front end of the support plate (23), and one end of the output shaft of the servo motor (5) is coaxially connected to a screw rod (50), The outer end of the screw rod (50) is plugged into the bearing in the bearing seat (24); the outer side of the screw rod (50) is threadedly connected to a slider (51); the top of the slider (51) is connected to a connecting column (52); the top of the connecting column (52) is fixedly connected to the fixing frame (22); The bottom surface of the bottom end of the support block (12) and the top surface of the front end of the base (1) are symmetrically provided with double circular rings (14); one end of the lifting screw (15) is provided with a through hole (150); the through hole (150) and the double circular ring (14) are connected by a pin; a rotating frame (16) is connected between the two lifting screws (15); the rotating frame (16) is in a square frame structure and is connected with a sleeve (160) in the middle of the upper and lower ends; the sleeve (160) is threadedly connected to the lifting screw (15); fixed blocks (17) are bonded to both sides of the middle of the support block (12); a square notch is provided on the top side of the fixed block (17) and is fastened with a strap (18); The front side surface of the pressure plate (20) is symmetrically provided with circular holes with internal threads, the outer side surface of the distance adjustment handle (3) is provided with threads and is threadedly connected to the circular hole of the pressure plate (20), and the rear end of the distance adjustment handle (3) is bonded with a push head (30) made of silicone material, the push head (30) is in an arc Y shape, which is conducive to pressing against the patella, and the distance adjustment handle (3) is rotated so that the push head (30) presses the patella of the rabbit's knee to wear and soften it.

2. The device for accelerating the establishment of a rabbit patellar subluxation malformation model according to claim 1, characterized in that: A T-shaped through slot is provided at the top of the track (41), and the size of the rear end of the slide (40) is adapted to the size of the through slot of the track (41).

3. The device for accelerating the establishment of a rabbit patellar subluxation malformation model according to claim 2, characterized in that: A motor (6) is coaxially connected to the central axis of the circular wheel (43), and the motor (6) is fixedly connected to the leg rest plate (10).

Images