Because hip stability greatly depends on hip range of motion it is crucial for a hip's postoperative range of motion to fall within a certain range in order to ensure maximum stability.

The zona orbicularis and proximal hip joint capsule are poorly understood, but recent studies seem to confirm that the proximal to middle part of the articular capsule, including the zona orbicularis, acts biomechanically as a locking ring wrapped around the femoral neck and thus is a key structure for hip stability in distraction.