Patent ID: 8308773

Claim:
A pedicle screw including: a screw body having: threads for engaging a spinal bone, a head on an upper end of the screw body, the head for supporting a rod relative to the spinal bone, a seat groove formed in the head, and an upper portion and both sides of the seat groove being open for receiving the rod, and a female threaded portion formed on an inner surface of the seat groove; and a locking bolt having: a male threaded portion formed on an outer periphery thereof which is threadedly engageable with the female threaded portion of the seat groove to engage and lock the rod to the head of the screw body, and a locking bolt groove formed within the locking bolt to have a predetermined depth on the outer periphery of the locking bolt in a spiral direction and extending radially inwardly from the male threaded portion into a root of the locking bolt.