Fibrous dysplasia is a bone disorder in which scar-like (fibrous) tissue develops in place of normal bone. As the bone grows, the softer, fibrous tissue expands, weakening the bone. Fibrous dysplasia can cause the affected bone to deform and become susceptible to fracture.
Most people with fibrous dysplasia are diagnosed during adolescence or early adulthood. Mild cases usually cause no signs or symptoms. More-serious cases of fibrous dysplasia may result in bone pain and deformity.
The basic cause of fibrous dysplasia is unknown. There's no cure for fibrous dysplasia. Treatment focuses on relieving signs and symptoms.
Fibrous dysplasia can affect any bone in your body. Most people with the disorder have only one affected bone — a form called monostotic fibrous dysplasia — and develop no signs or symptoms. When the condition affects more than one bone, it's known as polyostotic fibrous dysplasia. Bones most commonly affected are:
Fibrous dysplasia may cause few or no signs and symptoms, particularly if the condition is mild. Signs and symptoms typically develop during the teens or 20s. If you have the polyostotic form, you're more likely to develop signs and symptoms, usually by age 10. More severe fibrous dysplasia may cause:
In rare cases, fibrous dysplasia may be associated with abnormalities in the hormone-producing glands of your endocrine system — such as your pituitary gland — that regulate various functions throughout your body. These abnormalities include:
When to see a doctor
If you or your child has been diagnosed with fibrous dysplasia, see your doctor if the pain:
Bones commonly affected by fibrous dysplasia
Fibrous dysplasia most commonly affects your body's long bones — such as the bones in your arms and legs — and the ribs, pelvis, skull and facial bones. ...
You develop fibrous dysplasia before birth, and its development has been linked with a gene mutation that affects the cells that produce bone. No one knows what causes the mutation, but it isn't inherited from your parents, and you can't pass it on to your children.
Bones are living tissue, so even after you stop growing, your bones are in a continuous process of renewal known as remodeling. In the process, certain bone cells (osteoclasts) tear down (resorb) bone, while other cells (osteoblasts) rebuild bone. Fibrous dysplasia disrupts the process, causing old bone to break down faster and replacing normal bone tissue with softer, fibrous tissue.
Besides bone fractures, severe fibrous dysplasia can lead to:
Preparing for your appointment
Most people with fibrous dysplasia don't have any symptoms and are diagnosed when an X-ray taken for another reason reveals signs of fibrous dysplasia.
However, in some cases you or your child may experience pain and other symptoms that lead you to schedule an appointment with your family doctor or your child's pediatrician. In some cases, you may be referred to a doctor who specializes in treating bone and muscle injuries or disorders (orthopedic surgeon).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready for your appointment, and what to expect from the doctor.
Prepare a list of questions so that you can make the most of your limited time with your doctor. List your questions from most important to least important in case time runs out. For fibrous dysplasia, some basic questions to ask include:
In addition to the questions that you've prepared to ask your doctor, ask questions anytime during your appointment that you don't understand something.
What to expect from your doctor
What to do in the meantime
Tests and diagnosis
If you have monostotic fibrous dysplasia, you may not know it until it's discovered incidentally on an X-ray for another condition. If you have signs and symptoms, your doctor will perform a physical examination and order X-rays of the affected bones. On X-ray, fibrous dysplasia appears as an abnormal section of bone (lesion) that has the hazy appearance of ground glass.
In some cases, your doctor may order more tests to confirm the diagnosis or to determine the extent of the disorder. They include:
Treatments and drugs
If you have mild fibrous dysplasia that's discovered incidentally and you have no signs or symptoms, your risk of developing deformity or fracturing your bone is low. Your doctor can monitor your condition with follow-up X-rays every six months. If there's no progression, you don't need treatment.
If you develop signs and symptoms, treatment may include medications or surgery.
Little is known about the use of bisphosphonates for children and adolescents, but some studies indicate they may help relieve pain in children and adolescents with severe fibrous dysplasia.
Oral bisphosphonates are generally well tolerated, but may irritate your gastrointestinal tract. If you can't tolerate oral bisphosphonates or if your doctor recommends a drug that's not available in oral form, you may receive bisphosphonates through a vein (intravenously). You can't take bisphosphonates if you have serious kidney disease or low blood-calcium levels.
Surgery may involve removing the bone lesion and replacing it with bone grafted from another part of your body or from bone tissue donated from a deceased donor. Your surgeon may insert metal plates, rods or screws to stabilize the bone and the graft. Risks include infection, blood clots and bleeding. In addition, a bone graft may not last.
Coping and support
Living with a condition such as fibrous dysplasia or having a child with the condition can be stressful. It may be helpful for you to:
Last Updated: 2011-07-07
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