Fibrodysplasia Ossificans Progressiva

Choi, In Ho; Chung, Chin Youb; Cho, Tae Joon; Lee, Duk Yong; Suk, Se Il; Kim, Woo Jin; Cho, Hyun Oh; Lee, Choon Sung; Yoo, Han Wook; Yun, Yeo Hon

Abstract

Fibrodysplasia ossificans progressive (FOP) is an extremely rare disabling disorder characterized by progressive heterotopic ossification associated with congenital digital malformations. The purpose of this study is to delineate the problems in diagnosis and treatment of this rare disease, and to present their solutions. Nine Korean FOP patients have been followed up for average 7.2 years. Their medical records and radiographs were reviewed, and they were reexamined directly or interviewed by telephone. There were 6 female and 3 male patients. The age at the time of this study averaged 13.3 years (range, 4 to 23). In 5 cases, the first clinical manifestation was migrating scalp and neck mass at the age of 1-2 years. The diagnosis was delayed for 3 year and 5 months at average although all the patients had pathognomonic big toe anomaly. Surgical excision of heterotopic ossification in an attempt to increase the joint motion was performed in 4 cases but in vain. Posterior spinal fusion in 1 case failed to prevent progression of scoliosis and trunk decompensation. Disodium etidronate, tried in 3 patients, brought no effective symptom relief. All the patients in their 20's were household ambulators. Understanding the clinical manifestation of this disease enables early diagnosis, by which unnecessary and harmful procedures such as surgical biopsy or excision can be avoided, although no effective treatment has been developed.