Fibrodysplasia ossificans progressiva also known as FOP is one of the rarest and most disabling genetic bone conditions known to medicine. FOP causes muscles, tendons, ligaments, and other connective tissues to turn into bones. Movement becomes limited in the affected areas of the body. People with FOP typically have malformed toes at birth, meaning the big toe is typically shorter than normal and points abnormally outward in a position called valgus deviation. Symptoms of FOP begin to appear in early childhood. Most people with FOP develop painful tumor-like bumps also known as fibrous nodules. Fibrous nodules are visible on the neck, shoulders and back. When a patient begins to generate new bone, what doctors call a flare; causes tissue swelling and joint stiffness. Flare-ups can last up to 6-8 weeks. Even during a flare-up, patients may experience low-grade fevers, mainly because the fever is part of an inflammatory reaction. In most cases, fibrodysplasia ossificans progressiva goes undiagnosed. One of the most common missed diagnoses is cancer due to the tumor-like nodes. When doctors try to remove the "tumor" they cause more damage because flare-ups typically develop after a person has suffered trauma to the body, such as a fall, small bump or even a small bag. Illnesses like the flu can also trigger flare-ups. In one case of FOP they did so much damage that they had to remove the patience arm. Experts estimate that the misdiagnosis rate of FOP may be 80% or higher. FOP occurs randomly and is not hereditary. Experts believe that one of the causes of fibrodysplasia ossificans progressiva is due to mutations in the ACVR gene that provides instructions to the body...... half of the document ...... At that time, physical therapy was recommended. Erin eventually learned to roll over, sit on her own, and walk throughout physical therapy. However, these milestones were significantly delayed and his balance was always off. Erin took a horrible fall off the couch and landed on her forehead. It was still swollen from the "allergic reaction" the previous month. A CT scan showed no bone fractures, but the goose egg that had developed took months to disappear. In 2008, she was officially diagnosed with FOP. Ashley Kurpiel lives in Georgia. She was adopted when she was nine weeks old. Just before she turned 3, she was misdiagnosed with cancer and had her right arm/shoulder amputated. Five months after her amputation she was correctly diagnosed with Fibrodysplasia Ossificans Progressiva, or more commonly known as FOP. She is the only amputee with FOP.