M61.10

Clinical Causes: Genetic mutation in the ACVR1 gene affecting bone growth regulation Inheritance pattern typically autosomal dominant, meaning only one copy of the mutated gene is sufficient for the disorder to manifest No current evidence links environmental factors or lifestyle choices to the development of MOP

Key Symptoms: Progressive formation of bony masses in soft tissues Restricted movement due to bone encroaching on joints and muscles Deformities of the toes, often present at birth (broad great toes) Episodes of flare-ups causing painful swellings and rapid ossification Loss of mobility and flexibility over time Potential complications include difficulty breathing or swallowing if critical structures are affected Overall, the condition causes a gradual decline in physical function

Diagnosis Path: Diagnosing myositis ossificans progressiva involves a combination of clinical evaluation and imaging studies. Healthcare providers look for characteristic signs such as unusual bone growth patterns and congenital deformities like toe malformations. Imaging techniques include X-rays and CT scans that reveal ectopic bone formation. Genetic testing may identify mutations in the ACVR1 gene, confirming the diagnosis. Since MOP is rare, specialists often collaborate to establish an accurate diagnosis.

Treatment Protocols: Avoidance of trauma, which can trigger flare-ups and new bone formation Use of medications such as corticosteroids during flare-up episodes for pain and inflammation relief Physical therapy to maintain range of motion and prevent joint stiffness Surgical interventions are generally avoided, as they may stimulate additional ossification Assistive devices and braces to support mobility and daily functioning Ongoing research aims to find targeted therapies that could modify disease progression in the future