Fracture of the femoral head associated with posterior dislocation is rare. Although our experience is small, we present these cases because in them treatment carried out soon after the injury was more active than in most cases recorded in the literature.

In eight patients with capital fragments involving a third to a half of the femoral head, primary Vitallium-mold arthroplasty has yielded seven satisfactory results. Only four of these patients have been followed for prolonged periods, but, of the remaining, three appear to be repeating the progress of our earlier patients.

Our plan of treatment for these injuries is as follows:

1. Primary Vitallium-mold arthroplasty is indicated if fracture of the femoral head involves a third to a half of the head. If reduction has been impossible and injury to the weight-bearing surface is present, then excision of the detached fragment and primary arthroplasty seem the treatment of choice.

2. In the unusual case, when anatomical reduction is possible by closed manipulation, a good result may sometimes be expected. If practical, it might be well to confirm reduction by stereoscopic roentgenograms or posterior oblique views as described by Waller.

3. When prompt closed reduction is possible, or when the fragment of the femoral head is small and does not involve the weight-bearing portion of the hip, a good result may be achieved by removal of the fragment without redislocating the hip.

Finally, we favor Vitallium-mold arthroplasty to a prosthesis. If later reconstructive surgery should be necessary, as it was in Case 8, it can be more easily accomplished.