Fibrodysplasia ossificans progressiva in children can often be
recognized at birth because of the presence of shortening of the great toe,
characteristic hallux valgus, and short thumbs. The majority of patients
have the onset of symptoms by the age of four years, but there is often a
delay of many months before the diagnosis is made. Early recognition will
allow protection of the child from injuries in which the damaged tissue
will serve as a focus of calcification. Most patients with this condition
are physically disabled. The site of onset and of greatest involvement is
axial. Biopsy and surgery are best avoided. Use of EHDP (disodium ethane
1-hydroxy, 1-diphosphonate, or disodium etidronate) is not as yet of proved
value in most patients. Data from this study support the concept that most
cases of this lesion arise as dominant mutations.