An adjustable compression screw

Abstract

The utility model discloses an adjustable pressurizing screw, including adjusting lever, blocking head, burying screw rod and screw cap, the both ends of blocking head are connected adjusting lever and burying screw rod respectively, and adjusting lever, blocking head and burying screw rod are integral type structure, the shape of blocking head is shuttle shape. The lower part of burying screw rod is provided with pressurizing screw thread, and the upper end of adjusting lever is provided with screw cap, and the screw cap is provided with internal hexagonal hole. The lower threaded section of burying screw rod is buried in femoral head, and the lower end of burying screw rod is located in the subchondral bone area of femoral head, the upper part of burying screw rod passes through the fracture of femoral neck, and the blocking head is embedded in greater trochanter. The utility model can pressurize femoral neck fracture end in time, not only stabilizes the fracture end, and further promotes the fracture healing. Greater trochanter is not pressed by screw cap for a long time, and the screw cap - bone gap enlargement and loosening caused by ischemic necrosis are avoided.

Description

Technical Field

[0001] This utility model relates to the field of femoral neck fracture fixation screw technology, and in particular to an adjustable compression screw. Background Technology

[0002] In clinical practice, femoral neck fractures require fixation with compression screws, but fixation failure often occurs due to decreased interlocking force between the compression screw and the bone. The reason for this is that when using conventional compression screws, the greater trochanter of the femur is subjected to prolonged pressure from the screw cap, leading to ischemic necrosis, which causes the cap-bone gap to widen and loosen. Utility Model Content

[0003] To address the aforementioned problems, this invention aims to provide an adjustable pressure screw to solve the problem of fixation failure caused by a decrease in the interlocking force between the screw and the femur.

[0004] The technical problem solved by this utility model can be achieved by the following technical solution: an adjustable pressure screw, including an adjusting rod, a blocking head, an embedded screw rod and a screw cap, wherein the two ends of the blocking head are respectively connected to the adjusting rod and the embedded screw rod, the lower part of the embedded screw rod is provided with a pressure thread, the upper end of the adjusting rod is provided with a screw cap, and the screw cap is provided with an internal hexagonal hole.

[0005] The lower threaded section of the embedded screw is embedded in the femoral head, with the lower end of the embedded screw located in the subchondral bone region of the femoral head. The upper part of the embedded screw passes through the fracture site of the femoral neck, and the blocking head is embedded in the greater trochanter of the femur.

[0006] The blocking head is spindle-shaped, and its transverse diameter is larger than the diameter of the embedded screw.

[0007] The adjusting rod, the blocking head, and the embedded screw are an integral structure.

[0008] The tail end of the embedded screw is provided with a pointed tip.

[0009] Compared with the prior art, this invention has the following advantages: It can apply pressure to the fractured ends of the femoral neck at appropriate times, stabilizing the fracture ends and promoting fracture healing. The greater trochanter of the femur is not subjected to prolonged pressure from the screw cap, avoiding the widening of the screw cap-bone gap and loosening caused by ischemic necrosis. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram illustrating the fixation of a femoral neck fracture using this utility model; Figure 3 This is a schematic diagram illustrating further pressurization and fixation of the present invention; In the diagram: 1-screw cap, 2-adjusting rod, 3-stopping head, 4-embedded screw, 5-pointed tip, 6-femur, 11-internal hexagonal hole, 41-pressure thread, 61-femoral head, 62-femoral neck, 63-greater trochanter of the femur, 64-lesser trochanter of the femur, 65-fracture site. Detailed Implementation

[0011] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the following description, in conjunction with specific illustrations, further elaborates on this utility model.

[0012] In the description of this utility model, it should be understood that the terms "one end", "the other end", "outer side", "upper", "inner side", "horizontal", "coaxial", "center", "end", "length", "outer end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0013] Combined with appendix Figures 1 to 3 As shown, this embodiment discloses an adjustable pressure screw, including an adjusting rod 2, a blocking head 3, an embedded screw 4, and a screw cap 1. The two ends of the blocking head 3 are respectively connected to the adjusting rod 2 and the embedded screw 4. The adjusting rod 2, the blocking head 3, and the embedded screw 4 are an integral structure. The lower part of the embedded screw 4 is provided with a pressure thread 41, the upper end of the adjusting rod 2 is provided with a screw cap 1, the screw cap 1 is provided with an internal hexagonal hole 11, and the tail end of the embedded screw 4 is provided with a pointed tip 5.

[0014] The lower threaded section of the embedded screw 4 is embedded in the femoral head 61, and the lower end of the embedded screw 4 is located in the subchondral bone region of the femoral head. The upper part of the embedded screw 4 passes through the fracture site 65 of the femoral neck 62. The blocking head 3 is embedded in the greater trochanter of the femur 63, and the screw cap 1 is located outside the skin on the outer side of the femur.

[0015] When fixation of the fractured ends of the femoral neck is required, the fracture is first reduced. After confirming ideal alignment of the fracture ends using C-arm fluoroscopy, it is then fixed with adjustable compression screws. The length and thickness of the embedded screw 4 are selected as needed.

[0016] like Figure 2 As shown, the adjustable compression screw is screwed into the greater trochanter of the femur 63 using conventional methods, continuing along the central axis of the medullary canal of the femoral neck 62, passing through the fracture end to reach the subchondral bone region of the femoral head 61. The fusiform stop head 3 is positioned precisely against the lateral edge of the greater trochanter of the femur 63. The compression screw is inserted by inserting a hexagonal screwdriver into the internal hexagonal hole 11 and rotating it.

[0017] The blocking head 3 is spindle-shaped, and its transverse diameter is larger than the diameter of the embedded screw 4. The blocking head 3 has a smooth surface, which serves both to apply pressure during screw insertion and to prevent scratching of the tissue during screw removal. Figure 3 As shown, the screw cap 1 of the adjusting rod remains outside the skin on the outer side of the thigh. When the pressure at the fracture end of the femoral neck decreases and pressure needs to be increased, the adjustable pressure screw can be rotated as needed to achieve the pressure effect. Moreover, the greater trochanter of the femur 63 is not pressed by the screw cap for a long time, avoiding the increase in the screw cap-bone gap and loosening caused by ischemic necrosis.

[0018] When the pressure at the fracture site of the femoral neck decreases, pressure is generated at the fracture site through the antagonism between the pressure thread 41 and the spindle-shaped blocking head 3. For example... Figure 3 As shown, when more adjustable compression screws are screwed in, the three-part fusiform stop head embeds into the greater trochanter of the femur, increasing the pressure on the fracture ends of the femoral neck, stabilizing the fracture ends, and thus promoting fracture healing. The adjustable compression screws can be used intermittently without causing new trauma.

[0019] This device is not limited to use in femoral neck fractures, but can also be used for fractures in other locations that require compression.

[0020] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the utility model. Any simple modifications, equivalent changes, or alterations made to the above embodiments based on the technical principles of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. An adjustable pressure screw, comprising an adjusting rod (2), a blocking head (3), an embedded screw (4), and a screw cap (1), characterized in that: The two ends of the blocking head (3) are connected to the adjusting rod (2) and the embedded screw (4) respectively. The lower part of the embedded screw (4) is provided with a pressure thread (41), and the upper end of the adjusting rod (2) is provided with a screw cap (1). The screw cap (1) is provided with an internal hexagonal hole (11).

2. The adjustable pressure screw according to claim 1, characterized in that: The lower threaded section of the embedded screw (4) is embedded in the femoral head (61), the lower end of the embedded screw (4) is located in the subchondral bone region of the femoral head, the upper part of the embedded screw (4) passes through the fracture site (65) of the femoral neck (62), and the blocking head (3) is embedded in the greater trochanter of the femur (63).

3. An adjustable pressure screw according to claim 1, characterized in that: The blocking head (3) is spindle-shaped, and the transverse diameter of the blocking head (3) is larger than the diameter of the embedded screw (4).

4. An adjustable pressure screw according to claim 1, characterized in that: The adjusting rod (2), the blocking head (3), and the embedded screw (4) are an integrated structure.

5. An adjustable pressure screw according to claim 1, characterized in that: The tail end of the embedded screw (4) is provided with a pointed tip (5).

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