A 16-year-old boy with dystonia musculorum deformans underwent an operation for removal of femoral implants and excision of the prominence at the greater trochanter of the left hip. He was found to have fat embolism syndrome at postoperative day 1 as evidenced by confusion, respiratory symptoms, chest radiograph changes, raised erythrocyte sedimentation rate, thrombocytopenia and fat in the urine and sputum.