Sliding compression locking bone screw

Abstract

The present invention discloses a sliding pressure locking bone screw, comprising a bone screw and a limiting sleeve. The front end of the bone screw is provided with a thread A, the rear end of the thread A is provided with a polished rod, the rear end of the polished rod is provided with a sliding shaft, a step A is provided between the polished rod and the sliding shaft, the outer edge of the sliding shaft is smaller than the polished rod, a screw head is provided at the rear end of the sliding shaft, a step B is provided between the screw head and the sliding shaft, the outer edge of the screw head is larger than the sliding shaft, the screw head is provided with a thread B, and the rotation direction of the thread B is opposite to that of the thread A. The limiting sleeve is provided with a threaded hole, the threaded hole is matched with the thread B, the rear end of the threaded hole is provided with a step hole, the screw head is screwed backward through the threaded hole and placed in the step hole, the sliding shaft is provided in the threaded hole and slidably matched with the threaded hole, the step A slides backward until the limiting sleeve stops, and the sliding distance is set to 5 to 10 mm, and the rear end of the limiting sleeve is provided with a tapered thread, which is matched with the tapered thread hole of the bone plate.

Description

Technical Field

[0001] The invention provides a medical device, in particular to a sliding compression locking bone screw. Background Art

[0002] At present, goose head nails or PFAN intramedullary nails are commonly used in clinical treatment of femoral neck fractures. Both medical devices have different defects. The defect of goose head nails is that the threads of the bone screws used are set at both ends of the fracture line, and there is no postoperative pressurization function, so it cannot effectively promote the healing of the fracture surface. Although PFAN intramedullary nails have postoperative pressurization function, they require manual pressurization after surgery. Summary of the invention

[0003] The present invention provides a sliding compression locking bone screw, which overcomes the above-mentioned defects and mainly comprises a bone screw and a limiting sleeve.

[0004] The front end of the bone screw is provided with a thread A, which is used to screw into the femoral head at one end of the fracture line. The rear end of the thread A is provided with a smooth rod placed at the fracture line. The rear end of the smooth rod is provided with a sliding shaft. A step A is provided between the smooth rod and the sliding shaft. The outer edge of the sliding shaft is smaller than the smooth rod. A screw head is provided at the rear end of the sliding shaft. A step B is provided between the screw head and the sliding shaft. The outer edge of the screw head is larger than the sliding shaft. The screw head is provided with a thread B. The rotation direction of the thread B is opposite to that of the thread A. The thread B is set as a rectangular thread. The limiting sleeve is provided with a threaded hole, which is arranged in cooperation with the thread B, and a step hole is provided at the rear end of the threaded hole, and a tool hole is provided at the rear end of the step hole. The screw head is screwed backward through the threaded hole and placed in the step hole. The sliding shaft is arranged in the threaded hole and slides with the threaded hole. The step A slides backward to the front end of the limiting sleeve and stops. The sliding distance is set to 5 to 10 mm. The rear end of the limiting sleeve is provided with a tapered thread, which is screwed into the tapered thread hole of the bone plate or the tapered thread hole of the open nut of the CN201595922U universal locking bone plate. During the operation, the bone screw is rotated forward according to the rotation direction of the thread A, and the screw head stops at the bottom of the step hole. Continuing to screw in the bone screw will bring the two ends of the femoral neck closer and pressurize them.

[0005] Furthermore, the present invention provides a sliding compression locking bone screw, which mainly includes a bone screw A and a limiting sleeve A.

[0006] The front end of the bone screw A is provided with a thread C, which is used to screw into the femoral head at one end of the fracture line. The rear section of the thread C is cut off the crest to form a screw with an outer diameter smaller than the thread C, which is placed at the fracture line. The rear end of the screw is provided with a sliding shaft, a step A is provided between the screw and the sliding shaft, the outer edge of the sliding shaft is smaller than the screw, and the rear end of the sliding shaft is provided with a screw head A, a step B is provided between the screw head A and the sliding shaft, and the outer edge of the screw head A is larger than the sliding shaft. The limit sleeve A is provided with a threaded hole A, and the rear end of the threaded hole A is provided with a step hole. The thread C is screwed forward through the threaded hole A, and the sliding shaft slides through the threaded hole A. When the screw head A moves forward, it stops at the bottom of the step hole. The rear end of the step hole is provided with a tool hole. The step A slides backward to the front end of the limit sleeve A and stops. The sliding distance is set to 5 to 10 mm. The rear end of the limit sleeve A is provided with a tapered thread, which is screwed into the locking threaded hole of the bone plate or the tapered threaded hole of the open nut of the CN201595922U universal locking bone plate. During surgery, the bone screw A is rotated forward according to the rotation direction of the thread C, and the screw head A stops at the bottom end of the step hole. Continuing to screw in will bring the two ends of the femoral neck closer and apply pressure.

[0007] During the operation, two or three or more sliding compression locking bone screws of the present invention are generally used to perform bone setting treatment on the fractured femoral neck in cooperation with the bone setting plate.

[0008] Beneficial effects: A sliding pressure-locking bone screw is used, which not only maintains the function of the locking screw, but also adds the functions of manual pressure application during surgery and sliding pressure application after surgery. It is in line with the theory that the fracture ends are accelerated to heal after being stimulated by pressure, and realizes the purpose of manual pressure application of the femoral head and femoral neck during surgery and automatic pressure application of the femoral head and femoral neck after surgery. It is beneficial to both firm fixation and accelerated healing. Moreover, by limiting the design of pressure application distance, it reduces the excessive absorption of bone cells at the fracture line, which increases the gap, and further causes defects such as delayed femoral healing and bone nonunion, so that patients can avoid the pain of secondary surgery. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural schematic diagram of a first embodiment of a sliding compression locking bone screw of the present invention.

[0010] Figure 2 It is a structural schematic diagram of a second embodiment of a sliding compression locking bone screw of the present invention. DETAILED DESCRIPTION

[0011] The present invention is further described below with reference to the embodiments given in the accompanying drawings.

[0012] Figure 1This is a schematic structural diagram of a first embodiment of a sliding compression locking bone screw of the present invention, which mainly comprises a bone screw 1 and a limiting sleeve 2.

[0013] The front end of the bone screw 1 is provided with a thread A, which is used to screw into the femoral head at one end of the fracture line. The rear end of the thread A is provided with a smooth rod placed at the fracture line. The rear end of the smooth rod is provided with a sliding shaft 11. A step A is provided between the smooth rod and the sliding shaft 11. The outer edge of the sliding shaft 11 is smaller than the smooth rod. The rear end of the sliding shaft 11 is provided with a screw head 12. A step B is provided between the screw head 12 and the sliding shaft 11. The outer edge of the screw head 11 is larger than the sliding shaft 11. The screw head 11 is provided with a thread B. The rotation direction of the thread B is opposite to that of the thread A. The thread B is set as a rectangular thread. The limiting sleeve 2 is provided with a threaded hole 21, and the threaded hole 21 is matched with the thread B. The rear end of the threaded hole 21 is provided with a step hole, and the rear end of the step hole is provided with a tool hole. The screw head 12 is screwed backward through the threaded hole 21 and placed in the step hole. The sliding shaft 11 is arranged in the threaded hole 21 and slidably matches the threaded hole 21. The step A slides backward to the front end of the limiting sleeve 2 and stops. The sliding distance is set to 5 to 10 mm. The rear end of the limiting sleeve 2 is provided with a tapered thread, which cooperates with the tapered threaded hole of the open nut 3 of the CN201595922U universal locking bone plate.

[0014] Figure 2 It is a structural schematic diagram of a second embodiment of a sliding compression locking bone screw of the present invention, which mainly includes a bone screw A4 and a limiting sleeve A5.

[0015] The front end of the bone screw A4 is provided with a thread C, which is used to screw into the femoral head at one end of the fracture line. The rear section of the thread C is cut off the top to form a screw with an outer diameter smaller than the thread C, which is placed at the fracture line. The rear end of the screw is provided with a sliding shaft 41, and a step A is provided between the screw and the sliding shaft 41. The outer edge of the sliding shaft 41 is smaller than the screw. The rear end of the sliding shaft 41 is provided with a screw head A42, and a step B is provided between the screw head A42 and the sliding shaft 41. The outer edge of the screw head A42 is larger than the sliding shaft 41. The limiting sleeve A5 is provided with a threaded hole A51, and the rear end of the threaded hole A51 is provided with a stepped hole. The thread C is screwed forward through the threaded hole A51, and the sliding shaft 41 slides and fits through the threaded hole A51. When the screw head A42 moves forward, it stops at the bottom of the stepped hole. The rear end of the stepped hole is provided with a tool hole. The step A slides backward to the front end of the limiting sleeve A5 and stops. The sliding distance is set to 5 to 10 mm. The rear end of the limiting sleeve A5 is provided with a tapered thread, which is screwed into the locking threaded hole of the bone plate or the tapered threaded hole of the open nut 3 of the CN201595922U universal locking bone plate. During the operation, the bone screw A is screwed forward according to the rotation direction of the thread C, and the screw head A stops at the bottom of the stepped hole. Continuing to screw in will bring the two ends of the femoral neck closer and pressurize them.

Claims

1. A sliding compression locking bone screw, mainly comprising a bone screw (1) and a limiting sleeve (2), wherein the front end of the bone screw (1) is provided with a thread A and the rear end is provided with a screw head (12), and the rear end of the thread A is provided with a polished rod, characterized in that: A sliding shaft (11) is provided between the rear end of the polished rod and the screw head (12); the outer edge of the sliding shaft (11) is smaller than the polished rod and the screw head (12); the limiting sleeve (2) is provided with a threaded hole (21); the sliding shaft (11) is arranged in the threaded hole (21); the sliding shaft (11) and the threaded hole (21) are slidably matched; a step A is provided between the polished rod and the sliding shaft (11); a step B is provided between the screw head (12) and the sliding shaft (11); the step A slides backwards to the limiting sleeve (2) and stops.

2. A sliding compression locking bone screw according to claim 1, characterized in that: The screw head (12) is provided with a thread B, the direction of rotation of the thread B is opposite to that of the thread A, the threaded hole (21) is arranged in cooperation with the thread B, a step hole is provided at the rear end of the threaded hole (21), and a tapered thread is provided at the rear end of the limiting sleeve (2).

3. A sliding compression locking bone screw according to claim 2, characterized in that: The thread B is configured as a rectangular thread.

4. A sliding compression locking bone screw according to claim 2, characterized in that The screw head (12) is screwed backward through the threaded hole (21) and placed in the stepped hole.

5. The sliding compression locking bone screw according to claim 1, characterized in that: The backward sliding distance of the step A is set to 5-10 mm.

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