Abstract
We report three cases of femoral fracture, which subsequently developed osteosarcoma within the course of illness. The first patient presented with a spiral fracture treated with an interlocking femoral nail. He presented five months later with a painful knee swelling and was diagnosed with osteosarcoma. He was asymptomatic despite initial radiographs showed osteolysis at the distal metaphysis. The fracture united well and no evidence of marrow or soft tissue contamination. The second patient had a distal femoral fracture and underwent plate stabilization. Osteosarcoma developed at the united fracture site three years later. Both survived six to seven years without evidence of disease following the standard treatment protocol. The third patient had a closed distal third fracture treated with dynamic compression plating. He presented with an osteoblastic lesion in the proximal femur three years later. There was no initial radiological evidence of osteosarcoma one year before the clinical manifestation of the disease.