Early Signs and Symptoms of FOP
At birth, nearly 100 percent of people with FOP have a pathognomonic toe malformation, in which the big toes are shortened and bent inwards resembling a bunion (microdactyly with hallux valgus deformity).
Over 50 percent of affected individuals also have shortened thumbs (brachydactyly).
Since the flare-ups seen in FOP are frequently misdiagnosed as tumors, the recognition of these tell-tale signs are important as it may avoid any use of chemotherapy and prevent inappropriate medical interventions (e.g. biopsies) that exacerbate new bone formation.
Prompt referral for genetic consultation and ACVR1 gene testing for FOP can confirm a clinical diagnosis.
In infancy or early childhood additional symptoms may emerge, including:
Some images are courtesy of www.fopsverige.se
Kaplan et. al. Early diagnosis of fibrodysplasia ossificans progressiva. Pediatrics. 2008 May;121(5):e1295-300. doi: 10.1542/peds.2007-1980.