Pedicle screw assembly having a retractable screw tip for facilitating the securement of the pedicle screw assembly to a spinal vertebra

摘要

A pedicle screw assembly has a retractable screw tip that facilitates the securement of the pedicle screw assembly to a spinal vertebra in a minimally invasive fashion during an orthopedic surgical procedure. The pedicle screw assembly includes a body portion including a head and a shank. The shank includes an outer surface with a thread provided thereon, an end having a cutting tip provided thereon, and a bore extending inwardly from the end and having an internally threaded region provided therein. The pedicle screw assembly also includes a tip portion including a body having a cutting edge and a shank extending from the body. The shank has an externally threaded region provided thereon that cooperates with the internally threaded region of the bore to permit movement of the tip portion relative to the body portion between extended and retracted positions.