Ceramic-on-ceramic total hip arthroplasty: is squeaking related to an inaccurate three-dimensional hip anatomy...

Many factors were incriminated in the squeaking generation in ceramic-on-ceramic total hip arthroplasty (THA), including the cup positioning and design. However, the influence of the stem orientation has not been investigated and the true three-dimensional hip anatomy has never been compared to the contralateral healthy hip. Three patients, who underwent unilateral ceramic-on-ceramic THA, complained of squeaking. CT-scans were performed to compare the true three-dimensional hip anatomy to the contralateral healthy hip. All patients presented evidence of posterior neck-rim impingement with a two-fold increase in the global anteversion (above 75°) comparatively to the healthy hip. The excess of anteversion was on the cup side in 2 cases and on the stem side in 1 case. We conclude that squeaking in ceramic-on-ceramic THA could be related to a poor accuracy of 3D hip anatomy reconstruction which generated a posterior impingement and subsequent anterior edge loading because of excessive global anteversion.