- Malformation of the great toes is visible at birth.
- Flare-ups that worsen the condition occur spontaneously or following viral illnesses or physical trauma to the muscle such as: intramuscular childhood immunizations, falls, surgery, biopsy.
- Rogue bone growth progressively restricts movement.
- Often misdiagnosed as cancer
- The exact rate of progression is unpredictable, although there appears to be a pattern to the progression (e.g., upper body in childhood and lower body in adolescence)
- Rare, progressive genetic disorder that has an estimated prevalence of 0.88 per 1 million, or approximately a prevalence of 1 in 1 million.
- No ethnic, racial, or gender patterns.
- This video explains FOP https://www.youtube.com/watch?v=3StfoMjNK-s&t=1s