More on Atypical Fractures of the Femoral Diaphysis

Abstract

Our experience has been very similar to that described by Lenart et al. (March 20 issue)¹ in their report on atypical fractures of the femoral diaphysis. These fractures have a distinctive pattern and most likely represent completion of a stress fracture ( Figure 1 ). In our series,² 64.3% of the patients had involvement of the contralateral femur. In addition, 76% of the patients had documented prodromal symptoms of thigh pain, vague discomfort, or subjective weakness; these symptoms were often dismissed or treated as symptoms of spinal stenosis. “Giving way” of the involved limb immediately preceded the fall in 23.1% of the patients.³ We suggest that any patient receiving bisphosphonates who has thigh pain should undergo radiographic examination of the femur, and patients with a documented fracture should undergo radiographic examination of the contralateral femur. Prefracture diagnosis is challenging, as is defining the need for prophylactic fixation of a lateral cortical stress reaction that has been characterized by means of computed tomographic and magnetic resonance imaging (MRI) studies as a callus forming over an incomplete stress fracture.