Patent ID: 8882817

Claim:
A polyaxial pedicle screw, comprising: a housing having leading and trailing ends, and defining a longitudinal axis that extends through the leading and trailing ends; a bone screw member including a head and a threaded shaft extending from the head, the head being selectively securable within the housing; and an anvil positionable within the housing adjacent to the head of the bone screw member when the anvil and the head of the bone screw member are positioned within the housing, the anvil defining at least one groove in an outer surface of the anvil, the at least one groove extending transverse to the longitudinal axis and defining at least one flap that extends over the at least one groove, the at least one flap being flexibly attached to the anvil to enable the anvil to flex an amount sufficient to maintain the head of the bone screw member in constant contact with the anvil when the bone screw member is moved relative to the anvil.