Experience in the management of a complication of ipsilateral hip and knee arthroplasty is described. The cases of four female patients who sustained a femoral shaft fracture after ipsilateral hip and knee arthroplasty are reported. All fractures were treated operatively, and in all cases internal fixation devices failed. This complication of multiple joint arthroplasty presents a difficult management problem. Rigid fixation has a high failure rate for this type of fracture. Surface knee arthroplasty provides a better opportunity for internal fixation than a knee arthroplasty with a stemmed femoral component.