Modular megaprostheses in the treatment of periprosthetic fractures of the femur

BACKGROUND: Periprosthetic fractures (PPF) of the femur remain challenging, especially in patients with previous multiple revisions. Modular megaprostheses (mMPs) are rarely used in this indication; however, in some cases mMPs seem to be the last chance for limb salvage. We aimed to evaluate the clinical outcome of PPFs of the femur treated by modular mMPs at our institution. PATIENTS AND METHODS: In this study 33 patients (27 female; mean age 79 years) with a PPF after total hip or total knee arthroplasty (no tumor indications) were treated using modular proximal (mPFR; n = 12), distal (mDFR; n = 14) or total (mTFR; n = 7) femur replacement. A retrospective evaluation regarding mortality and revision rates was performed. Failures with need for revision were classified. RESULTS: At a mean follow up of 60 months (range 0–178 months), the total mortality rate as well as total revision rate were both found to be 39%. At 1 year follow-up the mortality rate was highest within the mDFR group, and less revisions were necessary in the mPFR group, however both findings were not significantly. Those patients, who had revision surgery before PPF, were found to have higher revision rate after implantation of mMP. In the mPFR group, dislocation was the most frequent failure, within the mDFR and the mTFR group infection. In one case amputation of the lower limb was necessary. CONCLUSION: mMPs represent a valuable option in PPFs of the femur. Infection and dislocation remain the most frequent complications. Prospective clinical studies are required to further define the outcome of mMPs in PPFs of the femur.