POLYAXIAL PEDICLE SCREW HAVING A ROTATING LOCKING ELEMENT

摘要

A screw and coupling element assembly for use with an orthopedic rod implantation apparatus includes a screw that has a head and a shaft that extends from the head, a coupling element that has a seat within which the head can be seated such that the shaft protrudes from the coupling element, and a locking element that can be mated with the coupling element and that thereafter can be selectively moved through a plurality of positions including an unlocked position and a locked position. When the locking element is in the unlocked position, the locking element presents a rod-receiving channel and the head is movable in the seat such that the shaft can be directed in a plurality of angles relative to the coupling element. When the locking element is in the locked position, a rod disposed within the rod-receiving channel is fixed relative to the coupling element and the head is immovable in the seat such that the shaft is fixed at an angle relative to the coupling element.