Postoperative magnetic resonance imaging evaluation of Pipkin fractures fixated with titanium implants: a report of two cases.

Previous studies have documented the effectiveness of magnetic resonance imaging for evaluating and following up the development of avascular necrosis of the femoral head. One of the limitations of this technique, however, is the distortion that is encountered with ferromagnetic screws. A traumatic fracture to the femoral head is a risk factor for avascular necrosis. The addition of internal fixation, which is often required in Pipkin-type fractures of the femoral head, creates significant image distortion on magnetic resonance scans used for postoperative follow-up. The artifact and field distortion present in magnetic resonance imaging when ferromagnetic screw fixation is used has been avoided at our institution by the use of titanium hardware. The authors, therefore, recommend the use of titanium screws in the fixation of Pipkin-type fractures in the hip joint.