Collapsible bone screw apparatus

摘要

A collapsible bone screw for healing bone fragments across a bone fracture includes an externally threaded inner screw member and an externally threaded outer screw member. The inner screw member is initially screwed into an inner bone portion. An unthreaded portion of the outer screw member is movably joined to the inner screw member. The outer screw member is screwed until it gains purchase in an outer bone portion. As impaction occurs over time, the collapsible bone screw apparatus may shorten in length as the two screw members slide, telescope or otherwise axially move toward each other to shorten the overall length, thereby preventing any portion of the screw apparatus from protruding out of the bone. A bone screw kit of multiple inner and outer screw members are provided as well as a method of surgically fastening bone fragments.