Resettable anti-rotation implant for femoral neck and intertrochanteric fractures

Abstract

The resettable anti-rotation implant is characterized in that the resettable anti-rotation implant comprises an outer sleeve and a pressurizing rotating shaft, a front screw hole and a rear screw hole are formed in the head and the tail of the outer sleeve respectively, and the thread directions of the front screw hole and the rear screw hole are opposite; the pressurizing rotating shaft is inserted into an inner hole of the outer sleeve and is in threaded connection with a front screw hole and a rear screw hole of the outer sleeve at the same time, a plurality of axial long grooves are formed in the front end of the outer sleeve in the circumferential direction of the outer sleeve and divide the outer sleeve into a plurality of expansion elastic pieces, and the expansion elastic pieces are expanded by rotating the pressurizing rotating shaft. The head and the tail of the outer sleeve horizontally move in the opposite directions at the same time, so that the expansion elastic pieces on the outer sleeve expand outwards at the same time, and the holding force of the outer sleeve on the femoral neck is increased. The femoral head cancellous bone repositor has high holding force in femoral head cancellous bone sclerotin, and the fracture separation part can be repositioned in a rotating and push-pull mode.

Description

Technical Field

[0001] The invention relates to an implant, in particular to a repositionable anti-rotation implant for femoral neck and intertrochanteric fractures, belonging to the technical field of orthopedic implant manufacturing. Background Art

[0002] In orthopedic clinical practice, femoral neck fractures and intertrochanteric fractures are relatively common diseases. Due to muscle traction after the fracture, the femoral neck will be displaced. If an incision is performed during surgery, the wound surface is too large, affecting blood circulation and making the patient's recovery period longer.

[0003] At present, minimally invasive methods are often used in clinical practice for reduction, and multiple bone needles are used for traction and rotation to achieve the reduction effect. The specific operation steps are: make an incision on the skin, insert multiple 3.2mm guide needles, and confirm the correct position of the guide needles through fluoroscopy; reduce the fracture by traction of the guide needles under C-arm fluoroscopy, and temporarily fix it with bone needles after the reduction is completed; the bone drill enters along the central main guide needle to expand the diameter of the nail channel; select a spiral blade or tension screw of appropriate length and screw it into the cancellous bone of the femoral neck along the main guide needle; according to the classification and stability of the fracture, choose whether to insert other screws to control the displacement and rotation of the fracture, and finally rinse the wound and suture it. Because the bone needle usually uses a threaded bone needle with a diameter of 3.2 mm, the diameter is relatively thin, and the thread on the bone needle has limited holding force in the cancellous bone of the femoral head, the reduction time is longer and the effect is poor. Summary of the invention

[0004] The purpose of the present invention is to provide a repositionable anti-rotation implant for femoral neck and intertrochanteric fractures, which has a high holding force in the cancellous bone of the femoral head and can reposition the fracture separation site by rotation, push and pull.

[0005] In order to achieve the above object, the technical solution of the present invention is: a repositionable anti-rotation implant for femoral neck and intertrochanteric fractures, the innovation of which is: comprising an outer sleeve and a pressurized rotating shaft,

[0006] The head and tail of the outer sleeve are respectively provided with a front screw hole and a rear screw hole, the thread directions of the front screw hole and the rear screw hole are opposite, the pressurizing rotating shaft is inserted into the inner hole of the outer sleeve, and the pressurizing rotating shaft is simultaneously threadedly connected with the front screw hole and the rear screw hole of the outer sleeve,

[0007] The front end of the outer sleeve is provided with a plurality of axial elongated grooves along its circumferential direction, and the plurality of axial elongated grooves divide the front end of the outer sleeve into a plurality of expansion spring pieces. When the pressurizing rotating shaft is rotated, the head and the tail of the outer sleeve move horizontally in opposite directions at the same time, so that the plurality of expansion spring pieces on the outer sleeve expand outward at the same time, so as to increase the holding force of the outer sleeve on the femoral neck.

[0008] In the above technical solution, three elastic grooves are provided on both sides of each expansion spring piece and along its length direction for reducing the local structural strength and increasing the elastic capacity. Two of the elastic grooves are located at the two ends of the expansion spring piece and are arc-shaped grooves, and the remaining elastic groove is located in the middle part of the expansion spring piece and is a long waist-shaped groove.

[0009] In the above technical solution, after the expansion spring piece expands outward, the middle part is bent and pushed outward, and at the same time the expansion spring piece is deformed into two equilateral segment structures. The length of the elastic grooves at both ends of the expansion spring piece is 1mm~5mm, and the length of the elastic groove in the middle part is 1mm~6mm.

[0010] In the above technical solution, the outer side surface of each expansion spring piece is provided with a plurality of anti-slip grooves for increasing the friction between the expansion spring piece and the bone interface.

[0011] In the above technical solution, the anti-slip groove is a V-shaped groove, the angle of the V-shaped groove is 40° to 90°, and the groove spacing is 0.5 mm to 5 mm.

[0012] In the above technical solution, the outer sleeve includes a connecting tube and an expansion tube which are connected as one and arranged coaxially, the tail of the connecting tube is provided with a rear screw hole, the head of the expansion tube has a rotating shaft connector, and the rotating shaft connector has a front screw hole.

[0013] In the above technical solution, an annular groove is provided at one end of the expansion tube and at the connection portion with the connecting tube, and an annular groove is also provided at the other end and located on the inner side of the rotating shaft connector. The notch direction of the annular groove is opposite to the notch direction of the elastic groove provided on the expansion spring sheet.

[0014] In the above technical solution, four arc-shaped expansion springs are provided on the outer sleeve.

[0015] In the above technical solution, four arc-shaped expansion springs are provided on the expansion tube, and the outer diameter of the connecting tube is larger than the outer diameter of the expansion tube.

[0016] In the above technical solution, the pressurized rotating shaft includes a shaft body, and the head and tail of the shaft body respectively have threaded sections that form threaded connections with the front screw hole and the rear screw hole, and the outer diameter of the threaded section at the head of the shaft body is larger than the outer diameter of the threaded section at the tail. At the same time, the tail threaded section of the shaft body also has an inner six holes for facilitating the insertion of a screwdriver and driving it to rotate.

[0017] The positive effect of the present invention is that after adopting the repositionable anti-rotation implant for femoral neck and intertrochanteric fractures of the present invention, since the present invention includes an outer sleeve and a pressurized rotating shaft,

[0018] The head and tail of the outer sleeve are respectively provided with a front screw hole and a rear screw hole, the thread directions of the front screw hole and the rear screw hole are opposite, the pressurizing rotating shaft is inserted into the inner hole of the outer sleeve, and the pressurizing rotating shaft is simultaneously threadedly connected with the front screw hole and the rear screw hole of the outer sleeve,

[0019] The front end of the outer sleeve is provided with a plurality of axial long grooves along its circumferential direction, and the plurality of axial long grooves divide the front end of the outer sleeve into a plurality of expansion spring pieces. When the pressurizing rotating shaft is rotated, the head and the tail of the outer sleeve move horizontally in opposite directions at the same time, so that the plurality of expansion spring pieces on the outer sleeve expand outward at the same time, so as to increase the holding force of the outer sleeve on the femoral neck.

[0020] A 3.2 mm guide needle was inserted into the center of the femoral neck in advance, and the correct position of the guide needle was confirmed by fluoroscopy.

[0021] The bone drill is inserted along the guide pin to establish and expand the channel path of the implant of the present invention.

[0022] The outer sleeve and compression shaft are advanced along the guide wire in the channel path and pushed into the femoral neck bone.

[0023] The pressurized rotating shaft is rotated, and the head and tail of the outer sleeve move horizontally in opposite directions at the same time, that is, the head and tail move relatively, so that the multiple expansion springs at the front end of the outer sleeve expand outward, expand the front end structure of the outer sleeve, and increase the contact area and friction between the outer sleeve and the bone interface. At this time, the fracture can be reduced under the C-arm fluoroscopic image through rotation, traction and other actions to ensure that the expansion springs of the outer sleeve have a high holding force on the bone interface. When the reduction is completed, the wound is rinsed and sutured;

[0024] Compared with the prior art, which uses multiple threaded bone needles with a diameter of 3.2 mm and requires pulling and rotating to perform very complicated resetting operations, the present invention can be relocated independently, and the operation is also simpler and faster; the prior art requires the insertion of the lag screw or spiral blade into the human body by screwing or knocking, while the present invention directly inserts the reaming channel of the drill bit, and through the expansion of the product head, the implant can be stably fixed, and resetting operations such as rotation and pulling can be completed. Therefore, the present invention is not only easy to operate, but also has a higher holding force in the cancellous bone of the femoral head, and can resetting the fracture separation part by rotating, pushing and pulling. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a specific implementation mode of the present invention;

[0026] Figure 2 It is a structural schematic diagram of the outer sleeve of the present invention;

[0027] Figure 3 yes Figure 2 Schematic diagram of the full cross-section structure;

[0028] Figure 4 It is a schematic diagram of the state after expansion of the present invention;

[0029] Figure 5 It is a three-dimensional structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described below with reference to the accompanying drawings and given embodiments, but is not limited thereto.

[0031] like Figure 1 , 2 As shown in , 3, 4, and 5, a repositionable anti-rotation implant for femoral neck and intertrochanteric fractures comprises an outer sleeve 1 and a pressurized rotating shaft 2, wherein the outer sleeve 1 is a hollow circular column structure, specifically,

[0032] The head and tail of the outer sleeve 1 are respectively provided with a front screw hole 11 and a rear screw hole 12, the thread directions of the front screw hole 11 and the rear screw hole 12 are opposite, the pressurizing rotating shaft 2 is inserted into the inner hole of the outer sleeve 1, and the pressurizing rotating shaft 2 is simultaneously threadedly connected with the front screw hole 11 and the rear screw hole 12 of the outer sleeve 1.

[0033] The front end of the outer sleeve 1 is provided with a plurality of axial elongated grooves along its circumferential direction, and the plurality of axial elongated grooves divide the front end of the outer sleeve 1 into a plurality of expansion spring pieces 13. When the pressurizing rotating shaft 2 is rotated, the head and tail of the outer sleeve 1 move horizontally in opposite directions at the same time, so that the plurality of expansion spring pieces 13 on the outer sleeve 1 expand outward at the same time, so as to increase the holding force of the outer sleeve 1 on the femoral neck.

[0034] Further, such as Figure 2 As shown, in order to reduce the structural strength at both ends and in the middle of the expansion spring piece and facilitate the expansion of the expansion spring piece, three elastic grooves 14 are provided on both sides and along its length direction of each expansion spring piece 13 for reducing the local structural strength and increasing the elastic capacity, two of which are located at both ends of the expansion spring piece 13 and are arc-shaped grooves, and the remaining elastic groove 14 is located in the middle of the expansion spring piece 13 and is a long waist-shaped groove.

[0035] Further, such as Figure 4 As shown, in order to make the expansion spring piece obtain a stable structure after expansion, it can be made into a triangular shape (roof shape), and a triangle can obtain a relatively stable structure. After the expansion spring piece 13 expands outward, the middle part is bent and pushed outward, and at the same time, the expansion spring piece 13 is deformed into two equilateral structures. The length of the elastic grooves at both ends of the expansion spring piece 13 is 1mm to 5mm, and the length of the elastic groove in the middle part is 1mm to 6mm.

[0036] Further, such as Figure 1 , 2 As shown in Figures 3, 4, and 5, in order to strengthen the friction between the expansion spring and the bone interface, improve the holding force of the implant in the bone, and prevent the implant from slipping during rotation and lifting operations, the outer side surface of each expansion spring 13 is provided with a plurality of anti-slip grooves 15 for increasing the friction between the bone interface.

[0037] Furthermore, in order to further improve the rationality of the structure, the anti-slip groove 15 of the present invention is a V-shaped groove, the angle of the V-shaped groove is 40° to 90°, and the groove spacing is 0.5 mm to 5 mm.

[0038] Further, such as Figure 3 As shown, in order to further improve the rationality of the structure and realize the expansion spring sheet of the expansion tube 17 after driving the pressurized rotating shaft to open, the outer sleeve 1 includes a connecting tube 16 and an expansion tube 17 which are connected as a whole and arranged coaxially, and the tail of the connecting tube 16 is provided with a rear screw hole 12, and the head of the expansion tube 17 has a rotating shaft connector 18, and the rotating shaft connector 18 has a front screw hole 11.

[0039] Further, such as Figure 3 As shown, in order to further reduce the structural strength of the two ends of the expansion tube and facilitate the expansion and expansion of the front end structure, an annular groove is provided at one end of the expansion tube 17 and at the connection position with the connecting tube 16, and an annular groove is also provided at the other end and located on the inner side of the shaft connector 17. The notch direction of the annular groove is opposite to the notch direction of the elastic groove 14 provided on the expansion spring piece 13.

[0040] Furthermore, in order to make the structure more reasonable and improve the stability of the structure after expansion, the outer sleeve 1 is provided with four arc-shaped expansion springs 13. When the total length of the outer sleeve 1 is reduced by 2mm, the expansion spring 13 is expanded upward by 10mm. The overall expansion tube 17 is expanded to a height of 20mm to 30mm.

[0041] Furthermore, in order to strengthen the overall strength of the outer sleeve and achieve the reduction of the femoral neck fracture, the outer diameter of the connecting tube 16 is larger than the outer diameter of the expansion tube 17. The expansion tube 17 of the present invention is provided with four arc-shaped expansion springs 13, which can ensure that the expansion structure of the expansion tube after expansion is more stable and reliable, and has a higher holding force in the cancellous bone of the femoral head.

[0042] Further, such as Figure 1As shown, in order to drive the rotation of the pressurized rotating shaft, the pressurized rotating shaft 2 includes a shaft body, and the head and tail of the shaft body respectively have threaded sections that form a threaded connection with the front screw hole 11 and the rear screw hole 12, and the outer diameter of the threaded section at the head of the shaft body is larger than the outer diameter of the threaded section at the tail. At the same time, the tail threaded section of the shaft body also has an inner six holes 21 for facilitating the insertion of a screwdriver and driving it to rotate.

[0043] The specific operation steps of the present invention are:

[0044] A 3.2 mm guide needle was inserted into the center of the femoral neck in advance, and the correct position of the guide needle was confirmed through fluoroscopy.

[0045] The bone drill is inserted along the guide pin to establish and expand the channel path of the implant of the present invention.

[0046] The outer sleeve 1 and the pressurized rotating shaft 2 are advanced along the guide needle in the channel path and pushed into the femoral neck bone (such as Figure 1 shown),

[0047] Insert the screwdriver into the inner six holes 21 of the pressurized rotating shaft 2 and rotate it, and the head and tail of the outer sleeve 1 move horizontally in opposite directions at the same time, that is, the head and tail move relatively, so that the multiple expansion springs 13 on the expansion tube 17 at the front end of the outer sleeve 1 expand outward at the same time, and the front end structure of the outer sleeve 1 (such as Figure 5 As shown in the figure, the contact area and friction between the outer sleeve and the bone interface are increased. At this time, the fracture can be reduced under the C-arm fluoroscopic image through rotation, traction and other actions to ensure that the expansion shrapnel of the outer sleeve has a high holding force on the bone interface. When the reduction is completed, the wound is rinsed and sutured.

[0048] Compared with the prior art, which uses multiple threaded bone needles with a diameter of 3.2 mm and requires pulling and rotating to perform very complicated resetting operations, the present invention can be relocated independently, and the operation is also simpler and faster; the prior art requires the insertion of the lag screw or spiral blade into the human body by screwing or knocking, while the present invention directly inserts the reaming channel of the drill bit, and through the expansion of the product head, the implant can be stably fixed, and resetting operations such as rotation and pulling can be completed. Therefore, the present invention is not only easy to operate, but also has a higher holding force in the cancellous bone of the femoral head, and can resetting the fracture separation part by rotating, pushing and pulling.

[0049] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A repositionable anti-rotation implant for femoral neck and intertrochanteric fractures, characterized in that: It comprises an outer sleeve (1) and a pressurizing rotating shaft (2), The head and tail of the outer sleeve (1) are respectively provided with a front screw hole (11) and a rear screw hole (12), the screw threads of the front screw hole (11) and the rear screw hole (12) are in opposite directions, the pressurizing rotating shaft (2) is inserted into the inner hole of the outer sleeve (1), and the pressurizing rotating shaft (2) is simultaneously threadedly connected with the front screw hole (11) and the rear screw hole (12) of the outer sleeve (1). The front end of the outer sleeve (1) is provided with a plurality of axially long grooves along its circumferential direction, and the plurality of axially long grooves divide the front end of the outer sleeve (1) into a plurality of expansion spring pieces (13). When the pressurizing rotating shaft (2) is rotated, the head and tail of the outer sleeve (1) move horizontally in opposite directions at the same time, so that the plurality of expansion spring pieces (13) on the outer sleeve (1) expand outwards at the same time, so as to increase the holding force of the outer sleeve (1) on the femoral neck.

2. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 1, characterized in that: Three elastic grooves (14) are provided on both sides of each expansion spring piece (13) and along its length direction, which are used to reduce the local structural strength and increase the elastic capacity. Two of the elastic grooves (14) are located at the two ends of the expansion spring piece (13) and are arc-shaped grooves, and the remaining elastic groove (14) is located in the middle of the expansion spring piece (13) and is a long waist-shaped groove.

3. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 2, characterized in that: After the expansion spring piece (13) expands outward, the middle part is bent and lifted outward, and at the same time, the expansion spring piece (13) is deformed into two equilateral segment structures. The length of the elastic grooves at both ends of the expansion spring piece (13) is 1mm to 5mm, and the length of the elastic groove in the middle part is 1mm to 6mm.

4. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 1, characterized in that: The outer side surface of each expansion spring piece (13) is provided with a plurality of anti-slip grooves (15) for increasing the friction force between the expansion spring piece and the bone interface.

5. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 4, characterized in that: The anti-slip groove (15) is a V-shaped groove, the angle of the V-shaped groove is 40° to 90°, and the groove spacing is 0.5 mm to 5 mm.

6. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 1, characterized in that: The outer sleeve (1) comprises a connecting tube (16) and an expansion tube (17) which are connected as one and arranged coaxially. The tail of the connecting tube (16) is provided with a rear screw hole (12). The head of the expansion tube (17) is provided with a rotating shaft connector (18). The rotating shaft connector (18) has a front screw hole (11).

7. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 6, characterized in that: An annular groove is provided at one end of the expansion tube (17) and at the connection portion with the connecting tube (16), and an annular groove is also provided at the other end of the expansion tube and located on the inner side of the rotating shaft connector (17), and the notch direction of the annular groove is opposite to the notch direction of the elastic groove (14) provided on the expansion spring sheet (13).

8. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 1, characterized in that: The outer sleeve (1) is provided with four arc-shaped expansion springs (13).

9. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 6, characterized in that: The expansion tube (17) is provided with four arc-shaped expansion spring pieces (13), and the outer diameter of the connecting tube (16) is greater than the outer diameter of the expansion tube (17).

10. The repositionable anti-rotation implant for femoral neck and intertrochanteric fractures according to claim 1, characterized in that: The pressurized rotating shaft (2) comprises a shaft body, wherein the head and tail of the shaft body respectively have threaded sections that are threadedly connected to the front screw hole (11) and the rear screw hole (12), and the outer diameter of the threaded section at the head of the shaft body is larger than the outer diameter of the threaded section at the tail. At the same time, the threaded section at the tail of the shaft body also has an inner hexagonal hole (21) for facilitating the insertion of a screwdriver and driving it to rotate.

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