d="sp1005">A cohort of 1289 posterior approach primary THA cases was prospectively followed and component position measured radiographically.
d="sp2005">Cup malposition, with respect to the Lewinnek safe zone, was an independent risk factor for dislocation (OR1.88). Modifying the anteversion safe zone limits to 10-25° strongly predicted increased dislocation risk (OR2.69). No dislocations occurred within a zone defined by a circle centered at 41.4° abduction and 17.1° anteversion, radius 4.3°.
d="sp3005">Utilizing a posterior approach specific safe zone of 10-25° anteversion and 30-50° abduction may minimize THA dislocations.
d="sp4005">Level III