Fibrous dysplasia

Fibrous dysplasia is an uncommon bone disorder in which scar-like (fibrous) tissue develops in place of normal bone. This can weaken the affected bone and cause it to deform or fracture.

In most cases, fibrous dysplasia affects only a single bone — most commonly the skull or a long bone in the arms or legs. This variety usually occurs in adolescents and young adults. People who have more than one affected bone typically develop symptoms before the age of 10.

Fibrous dysplasia is a genetic disorder and there's no cure. Treatment, which may include surgery, focuses on relieving signs and symptoms.

Symptoms Causes Complications

Fibrous dysplasia may cause few or no signs and symptoms, particularly if the condition is mild. More severe fibrous dysplasia may cause:

  • Bone pain
  • Bone deformities
  • Fractures
  • Nerve entrapment

Rarely, fibrous dysplasia may be associated with abnormalities in the hormone-producing glands of your endocrine system. These abnormalities may include:

  • Very early puberty
  • Thyroid gland problems
  • Light brown spots on the skin

When to see a doctor

See your doctor if you or your child develops bone pain that:

  • Increases with weight-bearing activity
  • Interrupts sleep
  • Doesn't go away with rest
  • Causes a limp

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