Periprosthetic fractures of the femur after hip and knee replacement. Analysis of treatment results in Al Razi Hospital.

OBJECTIVE To present the clinical and radiological results of treatment of periprosthetic fractures of the femur after hip and knee replacements. SUBJECTS AND METHODS Thirty-four patients (8 males and 26 females) with 34 fractures of the femur complicating hip and knee replacements are the subjects of this report. In 21 cases, the fracture affected the femur after hip replacement, and in 13 cases after knee replacement. Fractures around the hip replacement were classified according to Vancouver classification, and those around the knee replacement were classified according to Rorabeck. Location of fracture was defined as metaphyseal or diaphyseal. Arbitrary classification of fracture union was used. Fractures were considered to be either united or to have delayed union, after radiology. Conservative treatment and different methods of fixation were used. Clinical correlations between location of fracture and outcome were analyzed. RESULTS All 21 metaphyseal fractures after hip and knee replacements united. Eight diaphyseal fractures (6 after hip replacement and 2 after knee replacement) united. Five diaphyseal fractures after hip replacement had delayed union, and 4 fractures united after bone graft. In 1 case, fracture did not unite, the treatment was discontinued and the patient was lost to follow-up. CONCLUSION Our data show that metaphyseal fractures, regardless of type of implant, had better healing potential and did not require additional surgery. Diaphyseal fractures of the femoral shaft around the stem of femoral component of the hip or knee prosthesis required a bone graft and had less favorable outcomes. Women were more frequently affected by periprosthetic femoral fractures.