Internal Fixation Device for Patella Fracture

Abstract

The present invention discloses an internal fixation device for patellar fractures, which includes a knee-holding ring, patellar nails, adjustment straps and an adjustment mechanism. The edge of the knee-holding ring is connected to the adjustment straps and / or fixing straps, and the ends of the adjustment straps and / or fixing straps are sleeved on the two end parts of the corresponding patellar nails. Among them, the length of the two ends or the middle part of the adjustment straps can be adjusted to tighten each fixing strap and each adjustment strap. The straps in the present invention can be adjusted both radially and rotate moderately along the knee-holding ring, so as to adapt to the selection of nail insertion at different positions. When inserting the nails, there is no need to consider the constraints of the strap length and the hole positions at the strap ends, and the best position for nail insertion can be found without the aid of positioning instruments. After the nails are inserted, only the tension adjustment of the straps needs to be operated. The operation process during the surgery is simple and efficient.

Description

Technical Field

[0001] The present invention belongs to the technical field of internal fixation devices for patellar fractures. Background Art

[0002] The patella is the largest sesamoid bone in the human body, located in front of the lower end of the femur, within the quadriceps tendon. It is wide at the top and pointed at the bottom, with a rough front and an articular surface at the back, and is an important anatomical structure for straightening the knee joint. Patellar fractures account for 1% - 2% of all fractures and are often caused by primary rupture of the quadriceps tendon or direct impact on the femur. The patella has the function of protecting the knee joint and preventing friction between the quadriceps tendon and the femoral condyle cartilage surface. Patellar fractures are relatively common injuries. If not properly treated, patellar fractures may cause complications such as nonunion, joint adhesion, traumatic arthritis, and bone infection. Generally, there are various methods for internal fixation of patellar fractures. Clinically, the treatment methods for patellar fractures can be divided into two major categories: conservative and surgical treatments. Some existing technologies use an outer fixing strap for the patella retainer. In fact, it is an external fixing component that ties the strap to the knee back lining board. For example, the "centripetal expansion type patellar reduction air ring" with the publication number: CN23075272Y, the "patellar fracture fixator" with the publication number: CN2840957Y, the utility model "fixing device for patellar fractures" of CN 201968880 U, the "patellar fracture fixing device" with the publication number: CN 104644305 A, etc. These external fixing components are not directly fixed to the patella, cannot substantially fix the fractured patella, and their fixing tension is concentrated on the front of the patella, while there is no traction on the back of the patella, which easily causes the back crease to open, resulting in distortion during the recovery of the patella and slower recovery.

[0003] In the fixation after incising the patellar fracture site, such as the two surgical methods of Kirschner wire and wire tension fixation, memory alloy poly - patellar fixation with patella claws and tension band, the common problem is that a larger incision is required during the operation to insert the fixation device, and a second operation is also needed to remove the fixation device. The disadvantages of patella claw fixation are: high cost, increasing the burden on patients; the size of the patella claw needs to be accurately grasped, otherwise it is easy to be too large or too small, resulting in the patella claw not fitting well with the patella; due to the large area occupied by the patella claw, it causes isolation between the patellar skin and the patella, increasing the volume and the tension of the patellar skin, which is not conducive to suture and is easy to cause necrosis of the patellar skin and exposure of the patella claw; it has a good effect on transverse fractures, but the fixation effect on complex comminuted fractures and fractures of the lower pole of the patella is unreliable. Often, it relies on Kirschner wire fixation, reducing the scope of use. Instead of using Kirschner wire plus patella claws, it is better to simply apply Kirschner wire tension band fixation, making the operation redundant; due to concerns about the firmness of fixation, early functional exercise is restricted; it is not a generally applicable fixation method.

[0004] The large pressure per unit area at the contact part between the wire linear fixation band and the patella causes soft tissues to necrose, liquefy, absorb, and fibrose, resulting in the loosening of the tension band wire. Moreover, the irritation at the knotting part causes discomfort to the patient. For example, the "Patella fracture packing fixation device" with the publication number CN110960306 A includes a fixation band, a locking buckle, and a guiding device. The fixation band is a flexible structure. The fixation band needs to be wound around the patella driven by the guiding device and at least one fixation band crosses the fracture crease. The two ends of the fixation band are connected and tensioned and fixed through the locking buckle. This technology requires the use of a fixation band to wrap around the patella for packing and winding fixation. There are large knots at the knotting parts, which affect blood circulation, delay the recovery time, and even cause local tissue necrosis, and often cause discomfort to the patient due to irritation. Another example is the "Internal fixation device for patella fracture surgery" with the publication number CN 209186903 U, which includes a top column and a fixing block. A patella needle is installed inside the through hole of the bone. The top column is installed at the top of the patella needle, and the top column is located inside the installation groove, and the installation groove is opened on the upper surface of the bone. A wire is arranged at the outer surface top of the top column, and the fixing block is installed at the bottom of the patella needle. For this internal fixation device for patella fracture surgery, the top of the fixing device is a top column and is wound with a wire. After the wires are overlapped and pressed tightly and then wound to form large knots, the knots and the top column end protrude significantly to stimulate the skin, affecting blood circulation, delaying the recovery time, and even causing local tissue necrosis, and often causing discomfort to the patient due to irritation. The internal fixation object is easy to protrude from the skin, pierce the skin, cause pain and infection; there is more knee joint pain after surgery; it is not conducive to early exercise; the Kirschner wire is easy to loosen and displace, and the wire is easy to fall off, shortening the effective fixation time. Summary of the Invention

[0005] Aiming at the common defects and problems of various existing instruments for patella fractures, the present invention provides an internal fixation device for patella fractures that can adjust each cord and tighten it without much consideration of the nail-driving position, so as to simplify the operation difficulty, shorten the operation time, eliminate the nodes, and significantly reduce the protrusion degree.

[0006] The solution adopted by the present invention to solve its technical problems is as follows: A patella fracture internal fixation device includes a knee-holding ring and patella nails, and further includes an adjusting strap and an adjusting mechanism. The knee-holding ring is a circular rigid ring, and at least two adjusting straps and the remaining fixing straps are connected to its circular periphery, or all are connected to adjusting straps. One end of the fixing strap is fixed to the edge of the knee-holding ring, and the other end is connected with a loop. For the adjusting strap, when one end thereof is fixedly connected to the knee-holding ring, an end adjusting mechanism is provided between the other end and the patella nail or a length adjusting mechanism is provided in the middle of the strap. When one end thereof is provided with a radial adjusting mechanism with the knee-holding ring, the other end is connected with a loop. At least two patella nails penetrate through both sides of the patella fracture site approximately in parallel. The ends of each fixing strap and each adjusting strap are respectively sleeved on the corresponding ends of the patella nails, and when the radial adjusting mechanism or the end adjusting mechanism or the length adjusting mechanism is adjusted, each fixing strap and each adjusting strap are tensioned.

[0007] A patella fracture internal fixation device includes a knee-holding ring, fixing straps and patella nails, and further includes an adjusting strap and an adjusting mechanism. The knee-holding ring is a circular elastic ring, and at least one adjusting strap and the remaining fixing straps are connected to its circular periphery, or all are connected to adjusting straps. One end of the fixing strap is fixed to the edge of the knee-holding ring, and the other end is connected with a loop. For the adjusting strap, when one end thereof is fixedly connected to the knee-holding ring, an end adjusting mechanism is provided between the other end and the patella nail or a length adjusting mechanism is provided in the middle of the strap. When one end thereof is provided with a radial adjusting mechanism with the knee-holding ring, the other end is connected with a loop. At least two patella nails penetrate through both sides of the patella fracture site approximately in parallel. The ends of each fixing strap and each adjusting strap are respectively sleeved on the corresponding ends of the patella nails, and when the radial adjusting mechanism or the length adjusting mechanism is adjusted, each fixing strap and each adjusting strap are tensioned.

[0008] A patella fracture internal fixation device includes a knee-holding ring and patella nails. The knee-holding ring is a circular rigid ring or an elastic ring, and a plurality of socket holes are evenly distributed on its circumferential periphery. One end of a plurality of straps is fixed with a loop and the other end is fixedly connected with a movable loop, and the movable loop is sleeved in each socket hole, or one end of at least one strap is fixed with a loop and the other end is fixedly connected with a movable loop, and the movable loop is sleeved in each socket hole, and the rest are fixing straps. One end of the fixing strap is fixed to the edge of the knee-holding ring, and the other end is connected with a loop.

[0009] The described radial adjustment mechanism one: A plurality of radial perforations are provided along the circumferential edge of the rigid knee - hugging ring a in the radial direction, and elastic chucks are respectively arranged in each radial perforation. A strap - type adjustment cord c is used, one end of which is fixed with a collar, and the other end is provided with anti - slip reverse teeth. Each anti - slip reverse tooth is inserted into the corresponding radial perforation, and it is ensured that each chuck can automatically insert into the groove of the anti - slip reverse tooth; alternatively, a fixed cord is connected to the connecting part of the circumferential edge of the rigid knee - hugging ring a, and a strap - type adjustment cord c is connected through a plurality of radial perforations at the connecting part, and the fixed cord and the adjustment cord are used in cooperation.

[0010] The described radial adjustment mechanism two: A plurality of shallow grooves are provided along the circumferential edge of the rigid knee - hugging ring a in the radial direction, and screw holes are provided in the middle of the shallow grooves. There are inner groove teeth at the bottom of each shallow groove. A flat - ring - type adjustment cord d is used, one end of which is fixed with a collar, and the other end is connected to an adjustment plate. There is an adjustment hole in the middle of the adjustment plate, and there are anti - slip teeth on one side of the adjustment plate. After adjusting each anti - slip tooth radially, it is clamped in the corresponding shallow groove. A locking wire is inserted into the adjustment hole and thread - connected to the corresponding screw hole, and the surface of the adjustment plate is pressed by the cap part of the locking wire to fix it in the shallow groove; alternatively, a fixed cord is connected to the connecting part of the circumferential edge of the rigid knee - hugging ring a, and a flat - ring - type adjustment cord d is connected through a plurality of radial shallow grooves at the connecting part, and the fixed cord and the adjustment cord are used in cooperation.

[0011] The described radial adjustment mechanism three: A plurality of dovetail grooves are provided along the circumferential edge of the rigid knee - hugging ring a in the radial direction, and screw holes are provided in the middle of the shallow grooves. A dovetail - shaped adjustment cord e is used, one end of which is fixed with a collar, and the other end is connected to a dovetail plug. There is an adjustment hole in the middle of the dovetail plug, and there are anti - slip teeth on the outer side of the adjustment plate. Each dovetail plug is inserted into the corresponding dovetail groove in the radial direction and can be adjusted by sliding in the radial direction. A flat gasket a is also covered outside each dovetail plug. The anti - slip teeth on one side of the flat gasket a are matched and buckled into the anti - slip teeth outside the corresponding dovetail plug. The locking wire passes through the perforation of the flat gasket a and is further inserted into the adjustment hole of the dovetail plug. The locking wire is thread - connected to the corresponding screw hole, and the surface of the flat gasket a is pressed by the cap part of the locking wire to further press the dovetail plug to fix it in the shallow groove, or a fixed cord is connected to the connecting part of the circumferential edge of the rigid knee - hugging ring a, and a dovetail - shaped adjustment cord e is connected through a plurality of radial shallow grooves at the connecting part, and the fixed cord and the adjustment cord are used in cooperation.

[0012] The described length adjustment mechanism: One end of the adjustment cord is fixedly connected to the rigid knee - hugging ring a, and the other end is fixedly connected to a collar, and a length adjustment mechanism is provided in the middle.

[0013] The described end - part adjustment mechanism: A strip - shaped adjustment plate is fixed at the end of the cord. There is a flat - long adjustment hole in the middle of the adjustment plate. After the adjustment plate is sleeved outside the corresponding patella nail, the corresponding adjustment plate is pressed by the end caps and nuts at both ends of the patella nail. There is a perforation in the center of the gasket and it is sleeved outside the patella nail. There are anti - slip teeth on the surface of the adjustment plate and there are anti - slip teeth on the surface of each gasket.

[0014] The fixed cord or adjustable cord: One end thereof is provided with a movable buckle connected to the knee-hugging ring so as to facilitate replacing cords of different models for different patients.

[0015] The described knee-hugging ring is a composite ring of a rigid ring and a flexible ring.

[0016] Advantages of the present invention: The cord can be adjusted steplessly in the radial direction and can also rotate moderately along the knee-hugging ring, so as to adapt to nail driving at different positions. When driving a nail, there is no need to consider the constraints of the cord length and the hole position at the end of the cord, and the best position for nail driving can be found without the aid of positioning instruments. After nail driving, only the cord tension needs to be adjusted. The surgical procedure is simple and efficient.

[0017] Compared with the prior art in which a fixed band needs to be wound around the patella for packing and fixing, the present invention will not cause the problem of cord overlapping and piling up, will not have the problem of cord end knotting, and there is no need for the trouble of on-site winding. The treatment of each cord end is in a flattened state during the manufacturing process, so there will be no large protrusion problem after surgery. Through the above device of the present invention, the fragmented patella after fracture can be firmly closed together. The stepless adjustment function adopted enables the force on each fracture surface to be balanced, avoiding fracture dislocation and crevice opening. Moreover, the thickness of each cord and the buckle is small, which will not cause tissue protrusion and discomfort, and is conducive to shortening the fracture healing time.

[0018] The cord involved in the present invention can also be made of absorbable material, solving the problem of the need for a second operation to remove the implant, significantly reducing the surgical difficulty and saving at least half of the surgical time compared with the traditional method. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the internal fixation device with an end adjustment mechanism for the adjustable cord.

[0020] Figure 2 It is a schematic diagram of applying the internal fixation device of the present invention to the patella.

[0021] Figure 3 It is Figure 1 The enlarged schematic diagram of part A in

[0022] Figure 4 It is one of the schematic diagrams of the double-adjustable cord structure of the rigid knee-hugging ring.

[0023] Figure 5 It is the second schematic diagram of the double-adjustable cord structure of the rigid knee-hugging ring.

[0024] Figure 6 It is the schematic diagram of the single-adjustable cord structure of the elastic knee-hugging ring.

[0025] Figure 7Schematic diagram of an internal fixation device with a middle adjustment mechanism for an adjustment cord

[0026] Figure 8 Schematic diagram of an internal fixation device with a tie - type adjustment cord

[0027] Figure 9 Is Figure 8 Schematic diagram of the mating relationship between the tie and the perforation

[0028] Figure 10 One of the schematic diagrams of an internal fixation device with a radial adjustment mechanism for an adjustment cord

[0029] Figure 11 Is Figure 10 Stereoscopic structure diagram of the adjustment cord

[0030] Figure 12 Another schematic diagram of an internal fixation device with a radial adjustment mechanism for an adjustment cord

[0031] Figure 13 Is Figure 12 Partial enlarged view of the radial adjustment mechanism

[0032] Figure 14 Is Figure 12 Stereoscopic structure diagram of the adjustment cord

[0033] Figure 15 The third schematic diagram of an internal fixation device with a radial adjustment mechanism for an adjustment cord

[0034] Figure 16 The fourth schematic diagram of an internal fixation device with a radial adjustment mechanism for an adjustment cord

[0035] Figure 17 The fifth schematic diagram of an internal fixation device with a radial adjustment mechanism for an adjustment cord

[0036] Reference numerals in the figure: Rigid knee - holding ring 1a, Flexible knee - holding ring 1b, Fixed cord 2, End adjustment cord 3a, Middle - section adjustment cord 3b, Tie - type adjustment cord 3c, Flat - ring - type adjustment cord 3d, Dovetail - shaped adjustment cord 3e, Adjustment plate 301, Adjustment hole 302, Anti - slip teeth 303, Fixed band 304, Adjustment band 305, One - way bevel gear 306, Movable joint collar 307, Fixed joint collar 308, Fixed sleeve 309, Anti - slip reverse teeth 310, Chuck 311, In - groove teeth 312, Dovetail plug 313, Patella nail 4, Top cap 41, Flat gasket 42a, Wedge gasket 42b, Elastic wedge gasket 42c, Tooth piece 421, Base plate 422, V - shaped spring piece 423, Relief groove 424, Perforation 43, Anti - slip teeth 44, Nut 45, Self - tapping thread section 46, Screw sleeve 47, Screw rod 48, Collar 5, Socket hole 6, Radial perforation 7, Shallow groove 8, Screw hole 9, Lock wire 10, Dovetail groove 11 Specific implementation mode

[0037] To better understand the technical solution of the present invention, the technical solution and its application can be understood from different aspects through the following several relatively typical examples.

[0038] Example 1:

[0039] Figure 1 It is a rigid knee - hugging ring double - adjustable rope - type internal fixation device for patellar fractures. As can be seen from the figure, four ropes are respectively fixedly connected around the rigid knee - hugging ring 1a, namely two fixed ropes 2 and two adjustable ropes 3. On this basis, the number of fixed ropes and adjustable ropes can also be increased, usually in pairs, and it is advisable to keep the total number of ropes even, but the possibility of increasing to an odd number of ropes is not excluded. Or prepare multiple spare ropes and make deletion processing according to needs during the operation.

[0040] Figure 2 Shows that when Figure 1 the internal fixation device is in the state of the patella, it can be seen that, usually, two patellar nails penetrate both sides of the patellar fracture site approximately in parallel, and the ends of each fixed rope and each adjustable rope are respectively sleeved on the ends of the corresponding patellar nails. In special cases when the number of patellar nails or ropes needs to be increased, it is also required to add a fixed rope and an adjustable rope at the peripheral edge of the rigid knee - hugging ring 1a. When the number of ropes is increased to an odd number as described above, one patellar nail needs to be a blind - driven nail, and only the top - cap part is exposed, which is suitable for comminuted fractures. Thus, when designing the rigid knee - hugging ring and the number of each rope, different models can be set. In addition to the size models, different numbers of ropes fixedly connected to the periphery of the knee - hugging ring should also be considered. A better way is to fixedly connect multiple various ropes around the rigid knee - hugging ring at the same time, use the corresponding number of ropes according to needs, and the redundant ropes can be directly cut off after the operation.

[0041] For this embodiment, from Figure 1 it can be seen that the knee - hugging ring is a circular rigid ring. For the two fixed ropes 2 connected to the periphery of the rigid knee - hugging ring 1a, one end is fixed to the edge of the knee - hugging ring, and the other end is connected with a loop. When driving a nail (inserting the nail after drilling a hole), the loop is pulled to the position where the nail needs to be driven, and the nail tip is aligned with the inside of the loop to drive the nail. For the two end - adjustable ropes 3a connected to the periphery of the rigid knee - hugging ring 1a, from Figure 1 it can be seen that in this embodiment, one end of the adjustable rope is fixedly connected to the knee - hugging ring, and an end - adjusting mechanism is arranged between the other end and the patellar nail. Figure 1 The end - adjusting mechanism is shown in, and a strip - shaped adjusting plate 301 is fixed at the end of the rope. There is a flat - long adjusting hole 302 in the middle of the adjusting plate 301. After the adjusting plate 301 is sleeved on the outside of the corresponding patellar nail 4, the corresponding adjusting plate 301 is pressed by the end caps 41 and nuts 45 at both ends of the patellar nail. FromFigure 1 As can be seen, the flat gasket 42a, the wedge gasket 42b or the elastic wedge gasket 42c has a perforation 43 in the center and is sleeved outside the patella nail 4. There are anti-slip teeth 303 on the surface of the adjusting plate 301, and anti-slip teeth 44 on the surface of each gasket. After adjusting the positions of the adjusting plates, after screwing the screw nut 45, the upper and lower gaskets contract inward and squeeze the adjusting plates against the patella surface, so that each gasket and the corresponding adjusting plate are engaged through the anti-slip teeth to form an anti-slip fixing relationship.

[0042] The wedge gasket 42b and the elastic wedge gasket 42c can be set with different models respectively, mainly used to cooperate with the possible inclination angle (non-vertical) when the patella nail enters the patella. The wedge gasket 42b can be set with different models to achieve approximate matching with different inclination angles, but the elastic wedge gasket 42c has stronger adaptability and can adapt to almost any inclination angle. From Figure 3 As can be seen, the elastic wedge gasket 42c includes a tooth piece 421 and a bottom piece 422, both of which have a perforation 43 in the middle. A V-shaped spring piece 423 has a relief groove 424. The two pages of the V-shaped spring piece 423 are respectively fixed to the tooth piece 421 and the bottom piece 422, and the relief groove corresponds to each perforation.

[0043] From Figure 1 As can be seen, the upper end of the rod body of the patella nail 4 has a top cap 41, the lower end has a thread and is sleeved with a screw nut 45. The screw-type patella nail 4 can be inserted after drilling, or the patella nail 4 can be designed as a self-tapping screw with a self-tapping thread at the tip to facilitate direct screwing into and penetrating the bone. Another type of patella nail such as Figure 8 In the lower left part, there is a self-tapping thread section 46 at the upper end of the nail body, which is used to screw into the bone drill hole. When each cord is fixed and tightened, the end of the nail can be exposed outside the skin or the overly protruding part can be cut off.

[0044] When in use, as Figure 2 shown, first support the knee holding ring of the device in the middle area in front of the patella, then pull the fixing cord 2 to a suitable position, implant at least two patella nails 4 along a direction approximately perpendicular to the fracture gap. Each patella nail enters the loop of the fixing cord or the adjustment hole of the adjustment cord. As can be seen in the figure, the cords form an X shape, and the end loops or adjustment holes are successively located at the four ends of the two patella nails. See Figure 4 and Figure 5 , Figure 4 shows the situation where the two adjustment cords are respectively located at both ends of the same patella nail, Figure 5 shows the situation where the two adjustment cords are respectively located at the lower ends of the two patella nails. Both situations can achieve the adjustment and tensioning function. In addition, on this basis, it is also possible to design a situation with three adjustment cords and one fixing cord, and it is also possible to further design a situation with four adjustment cords.

[0045] After screwing the screw nut 45, the upper and lower gaskets contract inward and press each adjusting plate against the surface of the patella, but they are not completely crushed. When using a self-tapping screw body as shown in Figure 8 , there is no need to use the screw nut 45 anymore. Only need to screw the screw body so that the self-tapping section 46 enters the bone for fixation. At this time, move each adjusting plate to the appropriate position, maintain an appropriate tension, and then further screw each screw nut so that each screw nut presses each gasket, and then each gasket and the corresponding adjusting plate are engaged through the anti-slip teeth to form an anti-slip fixing relationship. It can be seen that through the above solution of this embodiment, the position of the lower screw is not limited by the length of the rope or the position of the loop, so as to facilitate finding the best position for the lower screw. When inserting the screw, there is no need to rely on positioning instruments, and only need to operate the rope tension adjustment after inserting the screw, so that the surgical process is simple and efficient. Moreover, each rope can be adjusted radially and can also rotate moderately along the knee-holding ring, so as to adapt to the selection of different positions for inserting the screw. It can also be seen that since the fixing relationship between the knee-holding ring and each rope is reinforced as a whole before leaving the factory, the connection between the two can be kept flat. The loops or adjusting plates at the ends of each patella screw can also be edge-shaped structures, so as to minimize the number of nodes, avoid the overlapping and thickening of each rope, prevent the appearance of rope knots, and prevent the internal fixation from protruding from the skin, piercing the skin, causing pain and infection. Compared with the current method of manually winding ropes or steel wires during the operation, the loop and adjusting plate adopted in this embodiment can realize the surgical operation conveniently and quickly, and the loop and adjusting plate are not as easy to fall off as the bundled ropes or steel wires, ensuring an effective fixation time.

[0046] Embodiment 2:

[0047] On the basis of Embodiment 1, an elastic knee-holding ring double-adjusting rope type patella fracture internal fixation device is adopted, as shown in Figure 6 . The device includes a knee-holding ring, a fixing rope, a patella screw, an adjusting rope and an adjusting mechanism.

[0048] The knee-holding ring is a circular elastic ring, and one adjusting rope and the other three fixing ropes are connected to its circular periphery. Among them, one end of the fixing rope is fixed to the edge of the knee-holding ring, and the other end is connected with a loop. When one end of the adjusting rope is fixedly connected to the knee-holding ring, an end adjusting mechanism is arranged between the other end and the patella screw or a length adjusting mechanism is arranged in the middle of the rope. When a radial adjusting mechanism is arranged at one end of it and the knee-holding ring, the other end is connected with a loop. At least two patella screws penetrate through both sides of the patella fracture site approximately parallelly. The ends of each fixing rope and each adjusting rope are respectively sleeved on the ends of the corresponding patella screws, and when adjusting the radial adjusting mechanism or the length adjusting mechanism, each fixing rope and each adjusting rope are tightened.

[0049] In this embodiment, since the elastic knee - holding ring 1b is adopted, the elastic knee - holding ring can be deformed moderately. After the three fixing straps are respectively fixed by the corresponding patella nails, by adjusting the last strap, i.e., the adjusting strap, during the process of tensioning the adjusting strap, the elastic knee - holding ring 1b can be pulled to deform moderately, so as to overcome the possible insufficient tension of the other three fixing straps (the two diagonal fixing straps can be tightened in advance when nailing).

[0050] Embodiment 3:

[0051] Based on Embodiment 1, the adjusting strap is replaced with another kind of adjusting strap as shown in Figure 7 to realize a new internal fixation device for patella fractures. This embodiment still takes the rigid knee - holding ring double - adjusting - strap type as an example. The fixing straps will not be described in detail. The adjusting strap is as shown in Figure 7 One end of it is fixedly connected to the rigid knee - holding ring 1a, and the other end is fixedly connected to the sleeve ring 5, and a length - adjusting mechanism is arranged in the middle part.

[0052] As shown in Figure 7 the middle - section adjusting strap 3b includes a fixed strap 304 and an adjusting strap 305. One end of the fixed strap 304 is fixedly connected to the sleeve ring 5, and the other end is connected to the fixed sleeve 309. One end of the adjusting strap 305 is connected to the movable sleeve ring 307 or the fixed sleeve ring 308, and the other end side wall is provided with a one - way inclined tooth 306 and passes through the fixed sleeve 309. The inner wall of the fixed sleeve 309 is provided with a convex block that can engage with the one - way inclined tooth 306, so that the one - way inclined tooth 306 can only enter the fixed sleeve 309 in one direction, realizing the relative tensioning of the fixed strap 304 and the adjusting strap 305 of the middle - section adjusting strap 3b. This middle - section adjusting strap 3b can also realize the expansion and contraction adjustment function like the end - section adjusting strap 3a in Embodiment 1. For the adjustment method of the adjusting strap, relative adjustment can also be realized by fixing the sleeve ring 5 at one end and the movable sleeve ring 307 at the other end and replacing different models. Figure 7 A plurality of socket holes 6 are evenly distributed around the periphery of the rigid knee - holding ring 1a in

[0053] Embodiment 4:

[0054] Based on Embodiment 1, the adjusting strap is replaced with another kind of adjusting strap as shown in Figure 8 to realize a new internal fixation device for patella fractures. This embodiment still takes the rigid knee - holding ring double - adjusting - strap type as an example (the possibility of adopting an elastic knee - holding ring is not excluded). A radial - adjusting mechanism is arranged between one end of the adjusting strap and the knee - holding ring, and the other end is connected with a sleeve ring 5. When adjusting the radial - adjusting mechanism, each fixing strap and each adjusting strap are tensioned.

[0055] Specifically, as shown in Figure 8As shown, a plurality of radial perforations 7 are provided radially along the peripheral edge of the rigid knee-holding ring 1a, and elastic chucks 311 are respectively provided in each radial perforation 7, as Figure 9 shown.

[0056] In this embodiment, a zip-tie type adjusting cord 3c is adopted. From Figure 8 it can be seen that a collar 5 is fixed at one end of the zip-tie type adjusting cord 3c, and anti-slip reverse teeth 310 are provided at the other end. Each anti-slip reverse tooth 310 is inserted into the corresponding radial perforation 7, and it is ensured that each chuck 311 can automatically insert into the groove of the anti-slip reverse tooth 310.

[0057] In this embodiment, a zip-tie type adjusting cord 3c is adopted, which can bend by itself. When this embodiment is applied, after fixing the corresponding collars with each patella nail, the nuts 5 are screwed to press each collar against the patella surface, and then the anti-slip reverse teeth 310 of some or all of the zip-tie type adjusting cords 3c are inserted into the corresponding radial perforations 7 and tightened.

[0058] Based on the above structure of this embodiment, it is also possible to design a fixed cord connected to the peripheral edge connection part of the rigid knee-holding ring 1a, and a zip-tie type adjusting cord 3c connected through a plurality of radial perforations 7. To realize the possible situation of using the fixed cord and the adjusting cord in cooperation.

[0059] Embodiment 5:

[0060] As Figure 10 shown, a plurality of shallow grooves 8 are provided radially along the peripheral edge of the rigid knee-holding ring 1a, and screw holes 9 are provided in the middle of the shallow grooves. At the same time, there are in-groove teeth 312 at the bottom of each shallow groove 8.

[0061] A flat-ring type adjusting cord 3d as Figure 11 shown is adopted, with a collar 5 fixed at one end and an adjusting plate 301 connected at the other end. From Figure 11 it can be seen that there is an adjusting hole 302 in the middle of the adjusting plate 301, and there are anti-slip teeth 303 on one side of the adjusting plate 301.

[0062] From Figure 10 it can be seen that after adjusting each anti-slip tooth 303 radially and clamping it in the corresponding shallow groove 8, the locking wire 10 is inserted into the adjusting hole 302 and threadedly connected to the corresponding screw hole 9, and the locking wire cap part is used to press against the surface of the adjusting plate to fix it in the shallow groove.

[0063] In this embodiment, a flat-ring type adjusting cord 3d is adopted, which can bend by itself. When this embodiment is applied, after fixing the corresponding collars with each patella nail, the nuts 5 are screwed to press each collar against the patella surface, and then the adjusting plate 301 of some or all of the flat-ring type adjusting cords 3d is stretched radially and clamped on the anti-slip teeth 303 of the corresponding shallow groove, and then the corresponding locking wire is screwed to fix the adjusting plate.

[0064] Based on the above structure of this embodiment, it is also possible to design to fix a rope belt at the connecting part of the peripheral edge of the rigid knee - holding ring 1a, and to connect a flat - ring - type adjustable rope belt 3d through a plurality of radial shallow grooves 8. This realizes the possible situation of using the fixed rope belt and the adjustable rope belt in combination.

[0065] Embodiment 6:

[0066] As Figure 12 shown, a plurality of dovetail grooves 11 are arranged radially along the peripheral edge of the rigid knee - holding ring 1a, and screw holes 9 are provided in the middle of the shallow grooves. An adjustable rope belt in the shape of a dovetail as Figure 14 shown is adopted. One end of the adjustable rope belt is fixed with a collar 5, and the other end is connected to a dovetail plug 313. Specifically, there is an adjustment hole 302 in the middle of the dovetail plug 313, and anti - slip teeth 303 are provided on the outer side of the adjustment plate 301.

[0067] As Figure 13 shown, each dovetail plug 313 is inserted radially into the corresponding dovetail groove 11 and can slide and adjust radially. A flat gasket 42a is also covered on the outer side of each dovetail plug 313. The anti - slip teeth 44 on one side of the flat gasket 42a are matched and buckled into the anti - slip teeth 303 on the outer side of the corresponding dovetail plug 313. The lock wire 10 passes through the through - hole 43 of the flat gasket 42a and is further inserted into the adjustment hole 302 of the dovetail plug 313. The lock wire 10 is threadedly connected to the corresponding screw hole 9, and the cap part of the lock wire presses the surface of the flat gasket 42a, thereby pressing the dovetail plug 313 to fix it in the shallow groove.

[0068] In this embodiment, the dovetail - shaped adjustable rope belt 3e is adopted, which can bend by itself. When this embodiment is applied, after fixing the corresponding collars with each patellar nail and screwing the nut 5 to press each collar against the patellar surface, then stretch and slide the dovetail plugs 313 of each part or all of the dovetail - shaped adjustable rope belts 3e radially into the corresponding dovetail plugs 313, and then screw the corresponding lock wires to fix the adjustment plates.

[0069] Based on the above structure of this embodiment, it is also possible to design to fix a rope belt at the connecting part of the peripheral edge of the rigid knee - holding ring 1a, and to connect a dovetail - shaped adjustable rope belt 3e through a plurality of radial shallow grooves 8. This realizes the possible situation of using the fixed rope belt and the adjustable rope belt in combination.

[0070] Based on the above embodiments, the knee - holding ring can also be designed as a composite ring of a rigid ring and a flexible ring. For example, a rigid or elastic ring is embedded on the upper surface or inside of the flexible ring. Based on the above concept, there can be some other embodiments of the present invention. For example, when a radial perforation is provided at the peripheral edge of the knee - holding ring in Embodiment 4, it can be changed to a dovetail - shaped radial groove. For example, for the shallow groove in Embodiment 5, the shallow groove can be not provided and the teeth in the groove can be directly changed to the engaging teeth on the surface of the knee - holding ring. All knee - holding rings can also be set as a composite two - layer structure. When applied to Embodiments 4 - 6, the upper and lower two - layer rings are combined together to form a radial perforation, or a closed shallow groove or a closed dovetail groove and other structures at the combined surface position. As Figure 16 When the upper and lower two - layer composite fixation is adopted, anti - slip patterns can be provided on the inner surfaces of the upper and lower rings (the upper and lower patterns are parallel or perpendicular. When parallel, they can be embedded in each other. When perpendicular, it is preferably to select a steel ring and a flexible belt that can be embedded in each other after pressing), and corresponding patterns that can fit with the anti - slip patterns are provided at the ends of the adjusting cord. They can be tightened radially respectively. When the upper and lower rings are pressed and fixed, each adjusting cord is fixed.

[0071] For example, as a deformation based on the implementation, when the knee - holding ring is designed as a single - layer structure, there can be a plurality of annular card slots on its upper surface, as Figure 15 shown. The lower surface of the adjusting plate at the end of the adjusting cord is matched and buckled with the annular card slot at this place. Each adjusting plate is adjusted in place radially. When fixed by a locking wire, the adjusting plate at the end of the adjusting cord can be pressed and fixed on the knee - holding ring. Or as Figure 17 shown. When the knee - holding ring is designed as a single - layer structure, screw holes are evenly distributed on its circumference, and its surface is smooth or provided with patterns. The inner end of the adjusting cord is flat and has a surplus. After tightening the adjusting cord and corresponding its flat position with the corresponding screw hole, a hole is drilled and a screw is installed into the screw hole.

[0072] At the same time, the patella needle on the upper surface of the protruding top post can be truncated, so as to effectively reduce the skin irritation at the top during fixation. Or, one end of the adopted patella nail has a threaded sleeve 47 with a nail cap, and the other end is a lead screw 48 with a top cap, as Figure 17 shown, and the length of the lead screw 48 screwed into the threaded sleeve 47 is controllable. And, the adjusting cords of the above - mentioned embodiments are used in combination, etc.

Claims

1. An internal fixation device for patellar fractures, characterized in that, It includes a knee-hugging ring and a patella nail, and also includes an adjusting strap and an adjusting mechanism. The knee-hugging ring is an annular rigid ring, and four straps are connected to its circular peripheral edge, including two adjusting straps and the rest of the fixing straps, or all are connected to the adjusting straps. One end of the fixing strap is fixed to the edge of the knee-hugging ring, and the other end is connected with a collar. For the adjusting strap, when one end is fixedly connected to the knee-hugging ring, an end adjusting mechanism is arranged between the other end and the patella nail or a length adjusting mechanism is arranged in the middle of the strap. When one end is provided with a radial adjusting mechanism with the knee-hugging ring, the other end is connected with a collar. At least two patella nails penetrate approximately parallel through both sides of the patella fracture site. The ends of each fixing strap and each adjusting strap are respectively sleeved on the corresponding ends of the patella nails, and when adjusting the radial adjusting mechanism or the end adjusting mechanism or the length adjusting mechanism, the fixing straps and the adjusting straps are tightened. The end adjusting mechanism: a strip-shaped adjusting plate (301) is fixed at the end of the strap. There is a flat and long adjusting hole (302) in the middle of the adjusting plate (301). After the adjusting plate (301) is sleeved on the outside of the corresponding patella nail (4), the corresponding adjusting plate (301) is pressed by the end caps (41) and nuts (45) at both ends of the patella nail. There is a perforation (43) in the center of the gasket and it is sleeved on the outside of the patella nail (4). There are anti-slip teeth (303) on the surface of the adjusting plate (301), and anti-slip teeth (44) on the surface of each gasket. The strap can be adjusted steplessly in the radial direction and can also rotate moderately along the knee-hugging ring. After the nail is inserted, only the tension adjustment of the strap needs to be operated. For the fixing strap or the adjusting strap: an activity buckle for connecting with the knee-hugging ring is arranged at one end to facilitate replacing straps of different models for different patients.

2. An internal fixation device for patella fractures, characterized in that, It includes a knee-hugging ring and a patella nail, and also includes an adjusting strap and an adjusting mechanism. The knee-hugging ring is a circular elastic ring, and four straps are connected to its circular periphery, including one adjusting strap and the remaining fixed straps, or all are connected to adjusting straps. One end of the fixed strap is fixed to the edge of the knee-hugging ring, and the other end is connected with a loop. When one end of the adjusting strap is fixedly connected to the knee-hugging ring, an end adjusting mechanism is arranged between the other end and the patella nail, or a length adjusting mechanism is arranged in the middle of the strap. When one end of the adjusting strap is provided with a radial adjusting mechanism with the knee-hugging ring, the other end is connected with a loop. At least two patella nails penetrate through both sides of the patella fracture site approximately parallelly. The ends of each fixed strap and each adjusting strap are respectively sleeved on the corresponding ends of the patella nails, and when adjusting the radial adjusting mechanism or the length adjusting mechanism, the fixed straps and the adjusting straps are tightened. The end adjusting mechanism: A strip-shaped adjusting plate (301) is fixed at the end of the strap. There is a flat and long adjusting hole (302) in the middle of the adjusting plate (301). After the adjusting plate (301) is sleeved on the outside of the corresponding patella nail (4), the corresponding adjusting plate (301) is pressed by the end caps (41) and nuts (45) at both ends of the patella nail. There is a perforation (43) in the center of the gasket and it is sleeved on the outside of the patella nail (4). There are anti-slip teeth (303) on the surface of the adjusting plate (301), and anti-slip teeth (44) on the surface of each gasket. The strap can be adjusted steplessly in the radial direction and can rotate moderately along the knee-hugging ring. After the nails are inserted, only the tension adjustment of the strap needs to be operated. The fixed strap or the adjusting strap: An activity buckle for connecting with the knee-hugging ring is arranged at one end thereof to facilitate replacing straps of different models for different patients.

3. The internal fixation device for patellar fracture according to claim 1, characterized in that, The first radial adjusting mechanism: A plurality of radial perforations (7) are arranged radially on the circular periphery of the rigid knee-hugging ring (1a), and elastic chucks (311) are respectively arranged in each radial perforation (7). An adjusting strap in the form of a cable tie (3c) is used. One end is fixed with a loop (5), and the other end is provided with anti-slip reverse teeth (310). Each anti-slip reverse tooth (310) is inserted into the corresponding radial perforation (7), and it is ensured that each chuck (311) can automatically insert into the groove of the anti-slip reverse tooth (310); or, a part of the fixed strap is connected to the circular periphery of the rigid knee-hugging ring (1a), and a part of the adjusting strap in the form of a cable tie (3c) is connected through a plurality of radial perforations (7), and the fixed strap and the adjusting strap are used in cooperation.

4. The internal fixation device for patella fractures according to claim 1, wherein, The second radial adjustment mechanism: A plurality of shallow grooves (8) are arranged radially along the peripheral edge of the rigid knee-holding ring (1a), and screw holes (9) are provided in the middle of the shallow grooves. Each shallow groove (8) has internal teeth in the groove bottom (312). A flat ring-shaped adjustment cord (3d) is used. One end of it is fixed with a collar (5), and the other end is connected to an adjustment plate (301). There is an adjustment hole (302) in the middle of the adjustment plate (301). One side of the adjustment plate (301) has anti-slip teeth (303). After adjusting each anti-slip tooth (303) radially, it is clamped in the corresponding shallow groove (8). A locking wire (10) is inserted into the adjustment hole (302) and is threadedly connected to the corresponding screw hole (9). The surface of the adjustment plate is pressed by the cap part of the locking wire to fix it in the shallow groove; or a fixed cord is connected to the connecting part of the peripheral edge of the rigid knee-holding ring (1a), and a flat ring-shaped adjustment cord (3d) is connected through a plurality of radial shallow grooves (8). The fixed cord and the adjustment cord are used in combination.

5. The internal fixation device for patella fractures according to claim 1, characterized in that, The third radial adjustment mechanism: A plurality of dovetail grooves (11) are arranged radially along the peripheral edge of the rigid knee-holding ring (1a), and screw holes (9) are provided in the middle of the dovetail grooves (11). A dovetail-shaped adjustment cord (3e) is used. One end of it is fixed with a collar (5), and the other end is connected to a dovetail plug (313). There is an adjustment hole (302) in the middle of the dovetail plug (313). The outer side of the adjustment plate (301) has anti-slip teeth (303). Each dovetail plug (313) is inserted into the corresponding dovetail groove (11) radially and can be adjusted radially. A flat gasket (42a) is also covered outside each dovetail plug (313). The anti-slip teeth (44) on one side of the flat gasket (42a) are matched and buckled into the anti-slip teeth (303) outside the corresponding dovetail plug (313). The locking wire (10) passes through the through hole (43) of the flat gasket (42a) and is further inserted into the adjustment hole (302) of the dovetail plug (313). The locking wire (10) is threadedly connected to the corresponding screw hole (9). The surface of the flat gasket (42a) is pressed by the cap part of the locking wire to further press the dovetail plug (313) to fix it in the dovetail groove (11), or a fixed cord is connected to the connecting part of the peripheral edge of the rigid knee-holding ring (1a), and a dovetail-shaped adjustment cord (3e) is connected through a plurality of radial shallow grooves (8). The fixed cord and the adjustment cord are used in combination.

6. The internal fixation device for patella fractures according to claim 1, characterized in that, The length adjustment mechanism: One end of the adjustment cord is fixedly connected to the rigid knee-holding ring (1a), and the other end is fixedly connected to the collar (5). A length adjustment mechanism is arranged in the middle.

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