Fibrodysplasia ossificans progressiva: report of two cases

Fibrodysplasia Ossificans Progressiva (FOP) is a rare hereditary connective tissue disease, genetically inherited as an autosomal dominant trait with complete penetrance but variable expressivity. Onset is typically in childhood and progressive involvement of the spine and proximal extremities leads to immobility and articular dysfunction. We present two cases with the typical features of FOP and a review of the pathogenesis, clinical manifestations and treatment options of this rare disease.