Patent ID: 8002807

Claim:
A dynamic screw assembly comprising: a fixation component that connects to a vertebral body, said fixation component comprising at least one inlet to allow a lubricant to pass inside said fixation component; a ring member coupled to said fixation component, wherein said ring member prevents said lubricant from leaking out of said fixation component; a stopper sealing said at least one inlet; a coupling member comprising an inwardly curved bottom portion and a bulbous end extending from said inwardly curved bottom portion, wherein said bulbous end comprises: at least one groove that houses said lubricant; and at least one slot to allow said bulbous end to fit into said fixation component and to limit a range of angulation of said coupling member with respect to said fixation component; a bumper mechanism coupled to said fixation component and said coupling member, wherein said bumper is shaped to coincide with said range of angulation; a longitudinal member coupled to said coupling member; and a blocker that retains said longitudinal member in said coupling member.