Fibrous dysplasia refers to a group of conditions that destroys and replaces normal bone with cystic bone growth. There are three types:

• Mono -- one bone is affected
• Polyostic -- several bones are affected
• McCune Albright -- in addition to the bone abnormalities, there are skin pigmentation and endocrine abnormalities.

The condition occurs in childhood, usually between 3 and 15 years of age. Bone lesions, unusual skin pigmentation, and endocrine gland abnormalities are symptoms. The bone lesions may stop when the child reaches puberty. The condition is not hereditary and the cause is unknown.

• Bone pain
• Difficulty walking
• Fractures or bone deformities (rare)

• A physical examination
• X-rays of bones

There is no cure for fibrous dysplasia, only treatment of the symptoms. Bone fractures or deformities will be treated as needed. The patient will be screened for the development of endocrine disorders as needed.

The outlook depends on the severity of the condition and associated problems.

• Rickets
• Gigantism or acromegaly
• Cushing's disease
• Hyperthyroidism
• Heart rhythm disturbance

Call your health care provider if symptoms of this condition are present, such as repeated bone fractures and unexplained bone deformity. Specialists in orthopedics (function of the skeleton), endocrinology (secreting glands), and genetics (inheritance of characteristics) may be involved in the diagnosis and care.

There is no known prevention of this group of disorders. The aim of care is to prevent specific complications, such as recurrent fractured bones, which may help limit the ultimate severity of this group of disorders.