Identifying global trends from case reports of fibrodysplasia ossificans progressiva: a scoping review

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare, disabling, genetic disorder characterized by progressive heterotopic ossification (HO). FOP care pathways are complex, and there are many underrepresented patients globally.

This scoping review aimed to identify global FOP case reports and investigate real-world management practices.

International/local databases and congress proceedings were searched. Publications reporting patient-level data for ⩾1 patient with an FOP primary diagnosis, published January 2000-January 2024, were eligible. Publication details, patient demographics, disease presentation, and care pathway were extracted. Data were charted through categorization of themes and frequency analyses.

Of 6064 publications screened, 369 were eligible, reporting on 541 patients with FOP. Most publications (82.4% (304/369)) reported an individual case; the remaining reported 2-25 cases. Cases were from 57 countries, most commonly in the Asia/Pacific region (47.0% (254/541)). Most patients had reportedly seen a single specialist (64.8% (59/91)), and care from multidisciplinary teams was reported for only 5.5% (5/91). HO (84.7% (458/541)) and great toe malformations (66.7% (361/541)) were the most commonly reported signs, though mobility limitations (46.2% (96/208)) and growths/lesions (38.5% (80/208)) were most common before diagnosis. The predominant drug classes reported for FOP treatment were corticosteroids (52.6% (102/194)) and nonsteroidal anti-inflammatory drugs (39.7% (77/194)). Surgeries were reported in 35.1% (190/541) of patients. Where specified, the most common surgery types were malformation correction/bone resection (43.6% (78/179)) and biopsies (34.1% (61/179)).

This scoping review synthesized valuable real-world insights from case reports of FOP, potentially supporting outreach initiatives in underserved regions and facilitating shared learnings on diagnosis and treatment. Although the inherent selection bias of case studies toward atypical cases limits definitive conclusions, some global trends in the clinical management practices were revealed.