Fibrodysplasia is a relatively common benign bone lesion. Extremity lesions are often located proximal to the long bones, most often in the femur, tibia, and fibula, and bilateral involvement may also occur. The skull and ribs are also more common. The disease occurs in adolescents and young adults, and the deformity of the bones is usually more severe in patients with early onset of the disease. The disease has a tendency to heal spontaneously with age, and current treatment focuses on the prevention and treatment of deformities. Severe deformities of the lower extremities can aggravate joint injuries and lumbosacral deformities and require early management. The effect of bisphosphonates is unclear. Some studies have shown that bisphosphonates do not significantly improve bone quality and patient symptoms. The new drug denosumab has shown some efficacy in preliminary studies, but its ultimate effect needs to be further observed. Some studies suggest that changes in hormone levels after pregnancy can exacerbate the development of bone lesions, so women are advised to consider childbirth after their condition has stabilized. This patient had a significant deformity of the right proximal femur, which was restored to normal after osteotomy and orthopedics.