Patent ID: 8840649

Claim:
A method of fixing one or more vertebral bones in a desired relationship, comprising the steps of: a. providing a plate member, a bone fastener and a locking element, said plate member having an aperture, said bone fastener adapted for connecting said plate member to the vertebral bone and including a stem, a bone engaging portion and a longitudinal axis, said locking element including a compression member and a fixation member, said compression member having a hole extending therethrough and at least one deformable wall; b. engaging said bone fastener to the vertebral bone; c. sliding said plate member and said locking element over said stem of said bone fastener so that said stem is located within said aperture of said plate member and said hole of said compression member; and d. bringing said compression member into proximity of the vertebral bone along said longitudinal axis of said bone fastener, wherein as said compression member is brought into proximity of the vertebral bone an increasing force is exerted against said fixation member, wherein said fixation member exerts a force against said plate member which causes a resultant force to be translated back through said fixation member to said compression member causing said deformable portion to clamp said bone fastener relative to said plate member, wherein said compression member and said fixation member include threads that engage one another as said compression member is brought into proximity of the vertebral bone along said longitudinal axis of said bone fastener.