Femoral stem failures in total hip arthroplasty: an unusual causal mechanism

Femoral stem failure in a 55-year-old man and a 33-year-old woman who had a Charnley and T28 stainless steel total hip arthroplasty, respectively, at the level of the transmedullar horizontal trochanteric wire, possibly resulted from intraoperative damage to the lateral aspect of the stem of the femoral component. The damage was inflicted by either the drill or the wire itself. After three and two years' follow-up there were no signs of cement loosening; yet, this component failure demonstrates that there was constant motion within the cement. The stem broke before there was any radiographic evidence of cement loosening, and the patients were basically asymptomatic. It is also clear from this experience that horizontal transmedullary transtrochanteric wiring should be viewed with concern for fear of initiating stress fracture in the femoral prosthetic stem if drilling is performed after the component is cemented.