PEDICLE SCREW, NUT AND LOCKING THREAD AT THE TAIL PART OF SCREW

摘要

A pedicle screw, a nut and a locking thread at the tail part of the screw, in which the thread profile of the locking thread for use at the tail part of said pedicle screw has an L-shaped section. The inner thread at said tail part of pedicle screw is said locking thread. Nut(3) has a out thread(4), the out thread(4) mates said inner thread, after the out thread(4) of the nut(3) screws in the inner thread of the tail part of pedicle screw, the inner thread(2) at said tail part of pedicle screw(1) engages with the out thread(4) of the nut(3). When locking, the thread of tail part of the screw and the thread of the nut can reduce the tension of the head of the screw, it is convenient to lock and take out the nut by an inner core of the nut, and it can avoid nut loosing and nut cracking.