Progressive osseous heteroplasia: an uncommon cause of ossification of soft tissues

Whereas the deposition of calcium within soft tissues is not infrequent, th e development of highly structured, mineralized tissue histologically ident ifiable as true bone is uncommon and can cause a variety of clinical featur es. This article reports the clinical and radiological features in a patien t with progressive osseous heteroplasia (POH), a recently identified disord er characterized by heterotopic ossification. The patient, a female, was 20 years of age at presentation. In addition to abnormal ossifications, she h ad short metacarpals at the fourth and fifth rays and short metatarsals at the second rays. Her parents were unaffected. Until the results of Rosenfel d and Kaplan in 1995 reporting POH in two boys, typical features had only b een reported in females (n = 8). POH is usually sporadic; however, familial associations and atypical phenotypes have been reported. (C) 2000 Editions scientifiques et medicales Elsevier SAS.