An Interlocking Intramedullary Nail Applicable to Metaphyseal Fracture Bone Defects

Abstract

The invention particularly relates to an interlocking intramedullary nail that can be applied to metaphyseal fracture bone defects, belonging to the field of medical devices, and comprising a main nail and a locking screw, wherein the main nail includes a distal end, a proximal end and an expansion part, wherein The distal end and the expansion part are arranged at both ends of the proximal end; the two sides of the distal end and the proximal end are provided with a plurality of threaded grooves; the locking screw is a full-threaded screw, and the locking screw is screwed into the threaded groove. In the invention, the locking screw is extruded and locked to fix with the multiple thread grooves on the outer periphery of the main nail, and the number of locking screws used is more than twice that of ordinary intramedullary nails. The diameter of the locking screw is relatively thick, the strength is high, and Easy to break, the main nail is a solid structure, the mechanical strength is stronger than the ordinary hollow intramedullary nail, and it is not easy to break, which can provide reliable stability of the metaphyseal fracture and bone defect, eliminate the abnormal movement of the fracture end, and is conducive to fracture healing.

Description

technical field [0001] The invention belongs to the technical field of medical devices, in particular to an interlocking intramedullary nail that can be applied to metaphyseal fracture bone defects. Background technique [0002] Severe fractures of the long bones of the extremities are often accompanied by bone defects. Bone defects can also occur after the resection of bone tumors and bone deformities. Therefore, clinical fractures and bone defects are common, for which intramedullary nails and plates and screws are the most effective methods of internal fixation. However, the plate is located on one side of the bone, which belongs to eccentric fixation and is prone to bending and fracture after longitudinal stress, while the intramedullary nail is located in the center of the bone and belongs to central fixation, and bending fracture is not easy to occur after longitudinal stress. Therefore, the mechanical effect of intramedullary nails is better than that of steel plates...

AI Technical Summary

Problems solved by technology

[0003] Most of the intramedullary nails currently used are hollow intramedullary nails. The advantage is that the guide wire with a smaller diameter can be used to guide the intramedullary nail into the medullary cavity, but the disadvantage is that the compressive and bending strength of the hollow intramedullary nail is lower than that of the solid marrow. Inner Nail

The locking screw holes of the currently used intramedullary nails are almost (99%) unthreaded, only application publication number: CN108433798A, application number: 2018103354383 The locking screw holes of the intramedullary nails are threaded, but the locking screw holes are located at the center of the main nail On the nail body, the strength of the intramedullary nail at the locking screw hole is weakened, and it is prone to breakage. The number of locking screws used in bone defects of metaphyseal fractures is limited

The length of the intramedullary nails currently used is fixed, and the intramedullary nails of different lengths are usually separated by 1cm. Sometimes there is no intramedullary nail of the right length during the operation. If the insertion is too long, the main nail is too short, and the proximal end of the main nail is buried in the In the medullary cavity, when the intramedullary nail is removed after the fracture heals, the proximal end of the main nail is embedded by callus. The tail of the main nail cannot be found or the callus growing into the tail affects the insertion and connection of the connector. If the main nail is too long, the main nail The tail protrudes under the skin at the opening of the bone, affecting the movement of the affected limb or causing pain, limitation of movement or other discomfort

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