Fibrous dysplasia of bone (FD) is a rare bone condition that can affect any bone in the body. The number of bones affected can vary: a single bone, two, three or more. The clinical severity is directly proportional to the number of bones affected. If it is in just a single bone (or maybe just two or three) then the disease can remain totally undetected for many years, and it is only when the person reaches 20, 30 or even 40 years old that it is noticed. Due to the bone problems that this disease can lead to, forms affecting multiple bones are often detected during childhood.

The exact frequency of the disease is unknown. It is likely that 2,000 to 3,000 people in France have the disease. The form that affects only one bone (monostotic) represents a half to two thirds of all patients with the condition.
The disease is caused by a gene mutation, is non hereditary, affecting certain bone forming cells.

The bones affected can deform, fracture or be the source of pain. Expansion of bones in the face can lead to facial deformities and compression of the nerves.

Abnormalities not affecting the bones can also be observed, such as café-au-lait skin pigmentation marks, endocrine abnormalities such as precocious puberty, as well as renal phosphorus wasting. When FD is present with skin pigmentation marks and endocrine abnormalities this is known as McCune-Albright syndrome.

There is currently no cure for this disease, caused by a defective gene, but there are active treatments for the different scenarios encountered when suffering with FD. Pain can be managed with medication, fractures and bone deformities can be operated on and endocrine problems can also be treated with medication.

Remember: not all forms of fibrous dysplasia are severe.

Created: 09 june 2010