Case report 686. Stress fracture at distal end of femur simulating "periosteal desmoid".

A 13-year-old female presented after repeated trauma with pain of the distal end of the thigh. The findings on plain films, bone scan, and CT were indeterminate. MRI accurately demonstrated a fracture line with bone marrow edema, suggesting the diagnosis of stress fracture. MRI patterns of stress fracture were considered and the importance of establishing the correct diagnosis was emphasized.