Gross trunnion failure after primary total hip arthroplasty.

Unfavorable outcomes from trunnion fretting and corrosion damage have been reported in the literature, gross failures of tapers in primary total hip arthroplasties have been less frequently reported. We report on 5 patients, who presented with gross trunnion failures of modular metal-on-polyethylene or ceramic-on-polyethylene bearings from 5 implant manufacturers, all necessitating revision surgery. None of these patients had an antecedent history of trauma, and the majority presented with pain or instability. No common factor was identified that may be predictive of these type of failures. Since there were 5 different stem designs, this suggests that it may be a rare generic phenomenon occurring with multiple designs. Currently, further investigations are necessary, including retrieval analysis, to identify risk factors that may predispose to such failures.