Opening type intramedullary nail

Abstract

The invention discloses an opening type intramedullary nail which comprises a nail member and a center-pole, wherein the nail member is in hollow pipe shape and includes a far-end and a near-end, the nail member is provided with a pinning aperture equipped with a pin, the center-pole includes a far end and a near end, the center-pole is arranged in the hollow pipe of the nail member in a movable manner, the pipe wall of the nail member far-end is provided with expansion slots longitudinally, the far end of the center-pole is provided with an expansion head, the maximum outside diameter of the expansion head is larger than the internal diameter of the pipeline section where the expansion slot is located, the near end of the center-pole is located at the near-end of the nail member, and the expansion head is connected with the center-pole to form a union body for synchronous rotation and moving, the near head section of the center-pole is equipped with a screw-threaded axial draught device.

Description

【Technical field】 [0001] The present invention relates to orthopedic instruments, more specifically, the present invention relates to an intramedullary nail for treating fractures. 【Background technique】 [0002] In the treatment of limb fractures, especially in the treatment of leg fractures, improper treatment is prone to sequelae such as delayed union, nonunion, or malunion of the fracture, which affects the therapeutic effect. In recent years, more advanced intramedullary nailing technology and equipment have been used in the treatment of femur and other limb fractures. Intramedullary nailing belongs to the internal fixation technology of fractures. Forming a whole, it can control the rotation and shear force of the fracture end to a certain extent, and prevent the rotation and displacement of the fracture site, thus expanding the indications of the intramedullary nail to comminuted, long oblique, and fractures at both ends of the femur. The stability of fixation improv...

AI Technical Summary

Problems solved by technology

However, in practice, it is found that there are still the following defects: 1) because the locking nail is located at both ends of the long bone, the surgical incision must be increased, the operation of installing the locking nail is cumbersome, and the side damage is large; The distance between the left and right swing of the inner nail and the main positioning rod changes, so that the height gauge cannot be positioned accurately, resulting in the locking hole of the intramedullary nail and the positioning hole on the main positioning rod are not on the same plane, which often leads to drilling failure, requiring CT or CT again. Drilling holes under X-ray not only prolongs the operation time, increases the difficulty of the operation, but also affects the effect of the operation; 3) The intramedullary nail and the corresponding locking nail have no pressurizing effect on the fracture line, and the fracture may still loosen or even stagger after fixation, thus Increase the fracture gap, which is not conducive to fracture healing; 4) After the intramedullary nail and the corresponding locking nail are fixed, a static fixation is formed, resulting in stress concentration on the intramedullary nail and the corresponding locking nail, resulting in the intramedullary nail and / or the corresponding locking nail. The locking nail is broken; 5) and the static fixation, due to the relationship between the elastic modulus, produces stress shielding on the fracture site, resulting in fracture nonunion

However, this device has similar disadvantages as above: there is also the large-headed conical nut and the central stud control head at two ends, because the tortuous medullary cavity causes difficulty in turning and advancing and retreating, which is not conducive to surgical implantation, nor is it conducive to taking out the lock after recovery. Nails, even lead to failure of the implantation operation or the large-headed conical nut completely detached from the control center stud and fell into the medullary cavity, increasing the difficulty of the removal operation and the pain of the patient

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