Trunnion Fracture of the Anatomic Medullary Locking A Plus Femoral Component

Fracture of the neck of the femoral component after total hip arthroplasty is an infrequent complication. We present a report of 2 cases of trunnion fractures of fully porous-coated femoral stems (AML A Plus, DePuy International, Leeds, England), which had been implanted for 6 and 7 years after the index procedures. In both cases, failure emanated from a region where the trunnion had been intentionally grooved; and in both cases, the diameter of the trunnion was small, and evidence of corrosion contributing to the initiation of the failure was noted. Although this is the first report of trunnion fractures in this particular implant design, a close monitoring of prostheses with this specific trunnion should be considered. In addition, further analysis of clinical results and complications with this implant is warranted.