Aim: The postoperative periprosthetic femoral fracture is a severe Complication after total hip surgery. Although, uncommon, such a fracture presents a major challenge to the orthopaedic surgeon.

In many cases the surgeon has to solve the problems of aseptic loosening, bone loss and fracture in one surgical procedure.

It is necessary to study a large population. Methods: We have analyzed the postoperative periprosthetic femoral fractures reported to the Swedish National Hip Registry. The databases of the registry, including 205 000 primary procedures and 37 000 reoperations, give a unique opportunity to analyze the prosthesis related femoral fracture. In the present study we report the retrospective data between 1979 and 2000, 1254 cases were found. The aim of the study were to estimatethe incidence of the periprosthetic fracture, classify the fractures and to analyze correlation to different factors. All living patients have received a self-administrated clinical outcome questionnaire. Results: The main results were that we found high frequencies of complications and reoperations and that 80% of the patients had a loose femoral component at the time of the periprosthetic fracture. A questionnaire was sent to the patient still alive. We found a high frequency of complication. 31% of the 374 had been reoperated. Conclusions: A future recommendation is to follow all patients with a hip prosthesis with regularly radiographic monitoring and try to intervene surgically before they sustain their fracture.