Fibrous dysplasia (FD) is an uncommon disorder of the skeleton that is rarely cancerous (less than 1 percent). This disorder results in fibrous bone-like tissue that replaces normal, healthy bone, causing the affected areas to be more susceptible to fractures (broken bone).
Fibrous dysplasia results from a genetic mutation (change) on chromosome 20.
This mutation happens on one gene that directs bone formation and growth, but what causes this mutation to occur remains unknown.
Fatigue, particularly in young children
Pain and weakness in the areas affected
Fractures or breaks
Misshapen bones (bone deformity)
Cafe au lait spots
Signs and symptoms of underlying endocrine disorders such as growth hormone excess, overactive thyroid and early puberty
FD is diagnosed by physicians with expertise in metabolic bone diseases. A physical exam, X-rays or other imaging, and blood or other tests may be used.
Individuals with milder forms of FD often live normal, otherwise healthy lives.
The prognosis is as widely variable as the disorder itself, and is based on the bones affected, whether other structures such as nerves are affected, and whether fractures occur.
Fibrous dysplasia can affect many bones in the body, but once it has established in the skeleton, it doesn’t spread.
Treatment for fibrous dysplasia depends on the severity of the disorder and the presence of symptoms.
In some cases, doctors simply monitor your bone health to make sure FD does not get worse.
Doctors frequently prescribe medications called bisphosphonates in an effort to ease pain and help prevent fractures.
Studies are ongoing to determine the effectiveness of denosumab (Prolia®), which is a drug commonly used to treat osteoporosis.
For some people, braces can help prevent bone fractures.
Surgery may become necessary if a bone affected by FD breaks. Surgery can stabilize the bone, correct disfigurement and prevent further fractures.
Sometimes doctors use metal plates, rods or screws to stabilize the bones. Contouring or
shavingaffected bone can result in rapid regrowth.