5. The dynamic pedicle screw of claim 1 , wherein: said housing is associated with a limit surface positioned to contact the deflectable post after a predetermined amount of deflection of the deflectable post away from alignment with the longitudinal axis of the bone screw; and wherein the compliant member has a cylindrical polymer bushing having an external diameter that mates to the bore of the housing and an internal lumen having a diameter that receives the elongated body of the deflectable post wherein the compliant member has a plurality of voids to prevent the cylindrical polymer bushing from being pinched between the deflectable post and the limit surface.
1. A spine stabilization device comprising: a bone screw having a distal end adapted to engage a bone and a longitudinal axis; a housing at a proximal end of said bone anchor; a longitudinal bore in said housing; a deflectable post having a proximal end, an elongated body and a distal end received in said bore, the proximal end of said deflectable post extending from the open end of said longitudinal bore and coaxially aligned with the longitudinal axis of the screw; and a compliant member positioned within the bore between the deflectable post and the housing such the compliant member flexibly resists pivoting of the deflectable post towards the housing, wherein the compliant member is shaped to control deflection of the deflectable post from alignment with the longitudinal axis of the bone screw.