Squeaking in metal-on-metal hip resurfacing arthroplasties.

While most reports of audible squeaking in total hip arthroplasty (THA) have focused on ceramic bearings, squeaking can occur in metal-on-metal bearings and may be an important clinical complication to consider during patient followup.We retrospectively identified 10 patients with squeaking metal-on-metal hip resurfacings.This study reports acetabular inclination angles and patient satisfaction, and describes two patients with squeaking resurfacings: one was revised and the other is pending revision. The minimum followup time in all 10 patients was 6 months (mean, 52 months; range, 6 to 79 months).The average time to onset was 11 months (range, 3-22 months). Hips started squeaking after bending, heavy activity, or prolonged periods of walking and the squeaking resolved within a week in all episodes. All hips except one were in the range of 45 degrees +/- 10 degrees inclination (median, 48 degrees ). One patient who reported squeaking at 6 weeks was revised 6 years postoperatively for a cystic mass. A second patient, now 76 months postoperative, who reports squeaking weekly after walking long distances, is scheduled for revision due to high serum metal ion levels and osteolysis in DeLee and Charnley Zone 1 of the acetabulum.We cannot conclude whether these complications are related to squeaking. Most patients with squeaking hip resurfacings do not appear to have an adverse response or clinical complication after 6 years. Squeaking in hip resurfacings is a short-term episode that could not be related to acetabular component inclination or decreased patient satisfaction.Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.