Patent ID: 8500782

Claim:
A fixation plate system comprising: an elongated plate having a first end, a second end and a longitudinal axis extending from the first end to the second end, the first end comprising a first elongated slot having a long axis and a short axis, the second end comprising a second elongated slot having a long axis and a short axis, the first and second elongated slots each having a seat portion, the short axis of the first elongated slot equal in length to the short axis of the second elongated slot; a semi-constrained fastener having a radially expandable head and a shank, the head of the semi-constrained fastener comprising a plurality of elastically deformable petals, the shank of the semi-constrained fastener having a diameter that is less than the lengths of the short axes of the first and second elongated slots so that the shank of the semi-constrained fastener is configured for insertion through the first and second elongated slots, the head of the semi-constrained fastener having a head profile with a diameter configured to engage the seat portions of the first and second elongated slots in an interference fit to inhibit translation of the head within the first and second elongated slots; and a dynamic fastener having a radially expandable head and a shank, the head of the dynamic fastener comprising a plurality of elastically deformable petals, the shank of the dynamic fastener having a diameter that is less than the lengths of the short axes of the first and second elongated slots so that the shank of the dynamic fastener is configured for insertion through the first and second elongated slots, the head of the dynamic fastener having a head profile with a diameter configured to engage the seat portions of the first and second elongated slots in sliding engagement to allow translation of the head within the first and second elongated slots, the diameter of the head of the semi-constrained fastener being greater than the diameter of the head of the dynamic fastener such that the semi-constrained fastener is selectively insertable into the first or second elongated slot in an interference fit to attach the plate to a first vertebra and restrict motion of the plate relative to the first vertebra, and the dynamic fastener is selectively insertable into the first or second elongated slot in a non-interference fit to attach the plate to a second vertebra and allow translation of the plate relative to the second vertebra.