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Question

Enhance the phenotype section for Fibrodysplasia Ossificans Progressiva with clinically important, PMID-backed manifestations only; add onset/frequency only when directly supported; remove or soften unsupported phenotype claims.

Output

FOP Phenotype Curation Note

Scope decisions

  • Kept the edit phenotype-only; no unrelated mechanism, treatment, or prevalence rewrites were performed.
  • Replaced weak phenotype evidence that had been anchored to a mouse palovarotene paper with human clinical abstracts that directly describe the phenotype.
  • Added missing but clinically important manifestations that recur across FOP case series and natural-history studies: flare-up pain/swelling, cervical spine anomalies, neck motion limitation, short thumb, conductive hearing loss, restricted mouth opening, and proximal tibial osteochondromas.
  • Used structured phenotype_contexts only where onset was directly stated in the abstract.
  • Kept frequency qualifiers only where an abstract gave a clear count or percentage that could be mapped directly to the HPO-aligned frequency bands.

Key phenotype evidence used

Hallux malformation

  • PMID:21116899

    A shortened great toe and hallux valgus were frequently found in patients with FOP.

  • PMID:21116899

    These findings were thought to exist from birth and may be a key to an early diagnosis.

Heterotopic ossification

  • PMID:36152026

    FOP is characterized by painful, recurrent flare-ups, and disabling, cumulative heterotopic ossification (HO) in soft tissues.

  • PMID:17572636

    Individuals with fibrodysplasia ossificans progressiva are born with malformations of the great toes and develop a heterotopic skeleton during childhood

Flare-up manifestations

  • PMID:26564023

    Fibrodysplasia ossificans progressiva (FOP) is a rare disorder characterized by episodes of acute pain and heterotopic ossification of soft tissue, and progressively limited physical function and social participation.

  • PMID:27025942

    The most common presenting symptoms of flare-ups were swelling (93%), pain (86%), or decreased mobility (79%).

Axial skeletal and mobility manifestations

  • PMID:7929490

    Twenty-six (65 per cent) of the patients had scoliosis, which, according to the clinical records and the recollection of the patients, had been present during childhood.

  • PMID:15959366

    In the FOP patient group, characteristic anomalies, including large posterior elements, tall narrow vertebral bodies,and fusion of the facet joints between C2 and C7, were observed.

  • PMID:15959366

    Generalized neck stiffness and decreased range of motion were noted in most children with FOP.

  • PMID:15959366

    FOP patients exhibit a characteristic set of congenital spine malformations.

Additional skeletal manifestations

  • PMID:25343126

    The thumb shortening and cervical spine abnormalities are other skeletal features often observed in FOP.

  • PMID:18245597

    Ninety percent of all patients had osteochondroma of the proximal part of the tibia.

Craniofacial, auditory, and respiratory manifestations

  • PMID:28390760

    As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan.

  • PMID:10499116

    The findings of both studies indicate that individuals with FOP are at risk for hearing loss and that the type of loss is predominantly conductive in nature

  • PMID:40597333

    Spirometry showed a uniform pattern of restrictive physiology in all eight participants with no significant difference amongst the group.

  • PMID:20194327

    The most common causes of death in patients with fibrodysplasia ossificans progressiva were cardiorespiratory failure from thoracic insufficiency syndrome (54%; median age, forty-two years) and pneumonia (15%; median age, forty years).

Modeling decisions

  • HP:0011986 Ectopic ossification was used instead of the narrower muscle-only term because FOP affects fascia, tendons, and ligaments as well as muscle.
  • HP:0002949 Fused cervical vertebrae was used as the best HPO anchor for the congenital cervical fusion phenotype, while the preferred_term preserves the broader clinical description of the cervical anomaly pattern.
  • HP:0012531 Pain and HP:0000969 Edema were used with more specific preferred_term labels for flare-up pain and swelling because HPO does not offer an FOP-specific flare-up term.
  • Frequency was retained only for:
  • Scoliosis from 26/40 patients = 65% (FREQUENT)
  • Proximal Tibial Osteochondromas from 90% of patients (VERY_FREQUENT)
  • Earlier blanket frequency claims for joint immobility, joint stiffness, and restrictive ventilatory defect were removed because the prior citations did not directly support those bands.