Fibrous dysplasia usually occurs in childhood. Most people have symptoms by the time they are 30 years old. The disease occurs more often in females.

Fibrous dysplasia is linked to a problem with genes (gene mutation) that control bone-producing cells. The mutation occurs when a baby is developing in the womb. The condition is not passed from parent to child.

Symptoms may include any of the following:

• Bone pain
• Bone sores (lesions)
• Hormone (endocrine gland) problems
• Fractures or bone deformities
• Unusual skin color (pigmentation), which occurs with McCune-Albright syndrome

The bone lesions may stop when the child reaches puberty.

Your health care provider will perform a physical examination. X-rays of bones are taken. An MRI may be recommended.

There is no cure for fibrous dysplasia. Bone fractures or deformities are treated as needed. Hormone problems will need to be treated.

The outlook depends on the severity of the condition and the symptoms that occur.

Depending on the bones that are affected, health problems that may result include:

• If skull bone is affected, there can be vision or hearing loss
• If a leg bone is affected, there can be difficulty walking and joint problems such as arthritis

Contact your provider if your child has symptoms of this condition, such as repeated bone fractures and unexplained bone deformity.

Specialists in orthopedics, endocrinology, and genetics may be involved in your child's diagnosis and care.

There is no known way to prevent fibrous dysplasia. Treatment aims to prevent complications, such as recurrent bone fractures, to help make the condition less severe.

Inflammatory fibrous hyperplasia; Idiopathic fibrous hyperplasia; McCune-Albright syndrome

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Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.