Three hundred and twenty-one periprosthetic femoral fractures.

Background: The purpose of this study was to determine the demographics, incidence, and results of treatment of periprosthetic fractures in a nationwide observational study.

Methods: In the years 1999 and 2000, 321 periprosthetic fractures were reported to the Swedish National Hip Arthroplasty Register. All of the associated hospital records were collected. At the time of follow-up, the Harris hip score, a health-related quality-of-life measure (the EuroQol-5D [EQ-5D] index), and patient satisfaction were used as outcome measurements. A radiologist performed the radiographic evaluation.

Results: Ninety-one patients, with a mean age of 73.8 years, sustained a fracture after one or several revision procedures, and 230 patients, with a mean age of 77.9 years, sustained a fracture after a primary total hip replacement. Minor trauma, including a fall to the floor, and a spontaneous fracture were the main etiologies for the injuries. A high number of patients had a loose stem at the time of the fracture (66% in the primary replacement group and 51% in the revision group). Eighty-eight percent of the fractures were classified as Vancouver type B; however, there was difficulty with preoperative categorization of the fractures radiographically. There was a high failure rate resulting in a low short to mid-term prosthetic survival rate. The sixty-six-month survival rate for the entire fracture group, with reoperation as the end point, was 74.8% +/- 5.0%. One factor associated with fracture risk was implant design.

Conclusions: On the basis of these findings, we believe that high-risk patients should have routine radiographic follow-up. Such a routine could identify a loose implant and make intervention possible before a fracture occurred. Furthermore, we recommend an exploration of the joint to test the stability of the implant in patients with a Vancouver type-B fracture in which the stability of the stem is uncertain.