Widespread periarticular new-bone formation in long-term comatose patients.

Widespread periarticular new-bone formation (myositis ossificans) was studied in 45 patients with brain damage who were in long-term coma. Thirty-six of these patients displayed myositis ossificans around at least one major joint. The development of myositis ossificans was shown to be independent of the sex and age of the patient and also of the aetiology, duration and outcome of the coma. Radiographic evidence first appeared between one and two months after the onset of coma. The maximal spread of myositis ossificans was reached in the first five months after the onset of coma. Progression of the disease was not observed after 14 months. Myositis ossificans was defined as a progressive self-limiting disease found in comatose patients.