Intrapelvic migration of the trial femoral head during total hip arthroplasty: is retrieval necessary? A report of four cases.

When testing intra-operative range of motion during a total hip arthroplasty procedure with trial components, there is potential for the femoral head to dissociate from the trial neck. We report the dissociation of the trial femoral head with migration of the head into the pelvis while checking for anterior stability of the total hip arthroplasty construct. Options for retrieval of the head are outlined.