A case report is presented of an 18-year-old boy with advanced fibrodysplasia ossificans progressiva. The patient's right hip was ankylosed in 35 degrees of flexion. Excision of the heterotopic bone from the right hip was followed by a combination of a single fraction irradiation (7Gy) given in the first postoperative day, and an 11-day treatment with indomethacin (25 mg, three times daily, orally). One year postoperatively, the patient ambulates nearly normally and he is able to sit and stand up without significant difficulty. Radiographs of the right hip showed a small amount of heterotopic bone formation at the operative site. In contrast with the results published in the literature, the clinical result of the operation is considered satisfactory. Further investigation of the combined use of indomethacin and single fraction irradiation as a preventive measure after surgical excision of heterotopic bone in patients with fibrodysplasia ossificans progressiva FOP should be performed.