Complications

Severe fibrous dysplasia can cause:

• Bone deformity or fracture. The weakened area of an affected bone can cause the bone to bend. These weakened bones also are more likely to fracture.
• Vision and hearing loss. The nerves to your eyes and ears may be surrounded by affected bone. Severe deformity of facial bones can lead to loss of vision and hearing, but it's a rare complication.
• Arthritis. If leg and pelvic bones are deformed, arthritis may form in the joints of those bones.
• Cancer. Rarely, an affected area of bone can become cancerous. This rare complication usually only affects people who have had prior radiation therapy.