The natural history of heterotopic ossification in patients who have fibrodysplasia ossificans progressiva. A study of forty-four patients.

Insights from a rare genetic disorder of extra-skeletal bone formation, fibrodysplasia ossificans progressiva (FOP)

“…Congenital malformation of the great toes ( Figure 1) is the earliest phenotypic feature of FOP [9][10][11]. This is the most recognizable skeletal feature of FOP, although other subtle skeletal changes (such as cervical spine fusions, short/broad femoral necks, and osteochondromas) also commonly occur [12][13][14].…”

The ACVR1 617G>A mutation is also recurrent in three Japanese patients with fibrodysplasia ossificans progressiva

“…FOP is the most severe disorder of heterotopic ossification and results in the postnatal formation of an ectopic skeleton (Cohen et al 1993;Kaplan et al 1993Kaplan et al , 2004. Heterotopic ossification in FOP begins in childhood and can be induced most often by trauma.…”

“…Heterotopic ossification in FOP begins in childhood and can be induced most often by trauma. The ossification is episodic and progressive, leading to extra-articular ankylosis of all major joints of the axial and appendicular skeleton (Cohen et al 1993;Kaplan et al 1993Kaplan et al , 2004, rendering movement impossible. Congenital malformation of the great toes is common.…”

Clinical Utility Gene Card for: Fibrodysplasia ossificans progressiva

“…The most common cause of death is cardiorespiratory failure (54%) from thoracic insufficiency syndrome, followed by pneumonia (15%), and complications of falls due to head injuries (11%). [17][18][19] Management (please describe)…”