Short answer · Medically reviewed summary · Last updated: 2026-05-08
Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic condition characterized by the progressive transformation of muscles, tendons, and ligaments into bone, effectively creating a second skeleton that restricts movement. While there is currently no cure, ongoing clinical research and natural history studies are actively investigating potential therapies to manage this complex condition. What is Fibrodysplasia ossificans progressiva? Often referred to as "Stoneman’s disease," Fibrodysplasia ossificans progressiva is a debilitating disorder where the body’s soft tissues undergo heterotopic ossification—turning into solid bone.
What is Fibrodysplasia ossificans progressiva
What is Fibrodysplasia ossificans progressiva? Plain-language, medically reviewed definition plus the lived reality told by patients.
Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic condition characterized by the progressive transformation of muscles, tendons, and ligaments into bone, effectively creating a second skeleton that restricts movement. While there is currently no cure, ongoing clinical research and natural history studies are actively investigating potential therapies to manage this complex condition.
What is Fibrodysplasia ossificans progressiva?
Often referred to as "Stoneman’s disease," Fibrodysplasia ossificans progressiva is a debilitating disorder where the body’s soft tissues undergo heterotopic ossification—turning into solid bone. This process typically begins in early childhood, often starting at the neck and shoulders before progressing down the body. Over time, Fibrodysplasia ossificans progressiva causes joints to lock, leading to significant physical immobility.
How does Fibrodysplasia ossificans progressiva affect the body?
Fibrodysplasia ossificans progressiva primarily impacts the skeletal and muscular systems. The condition is driven by a mutation in the ACVR1 gene, which causes the body's repair mechanism to malfunction, triggering bone growth in areas damaged by injury or inflammation. Unlike typical bone repair, this process is uncontrollable and permanent.
What are the key characteristics of FOP?
- Congenital indicators: Many infants with Fibrodysplasia ossificans progressiva are born with malformed big toes, a hallmark diagnostic sign.
- Flare-ups: New bone formation often follows "flare-ups," which may be triggered by minor trauma, viral illnesses, or muscle fatigue.
- Prevalence: It is exceptionally rare, with an estimated global prevalence of approximately 1 in 1.6 to 2 million individuals.
- Community impact: Currently, 49 people with Fibrodysplasia ossificans progressiva have joined the DiseaseMaps community to share their lived experiences and support one another.
Is there a cure for this condition?
While there is no treatment to stop the progression of Fibrodysplasia ossificans progressiva, physicians focus on pain management and avoiding procedures that might trigger bone growth, such as biopsies or intramuscular injections. Clinical researchers are currently evaluating promising new therapies through global patient trials.
Next steps
- Consult with an orthopaedic specialist experienced in rare genetic bone disorders.
- Connect with the Fibrodysplasia ossificans progressiva community at DiseaseMaps.org to find peer support.
- Discuss participation in natural history studies with your medical team to contribute to future research.
Medical disclaimer: This information is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment.
References
- NIH Genetic and Rare Diseases Information Center (GARD): Fibrodysplasia ossificans progressiva
- Orphanet: Rare disease database for FOP
- International FOP Association (IFOPA): Research and patient resources
- OMIM (Online Mendelian Inheritance in Man): ACVR1 Gene and FOP
