Paget’s disease of bone

DEFINITION

Paget’s disease of bone disrupts your body’s normal bone recycling process, in which old bone tissue is gradually replaced with new bone tissue. Over time, the affected bones may become fragile and misshapen. Paget’s disease of bone most commonly occurs in the pelvis, skull, spine and legs.

The risk of Paget’s disease of bone increases with age. Your risk also increases if any of your family members have the disorder. Complications of Paget’s disease of bone can include broken bones, hearing loss and pinched nerves in your spine.

Bisphosphonates — the medications used to strengthen bones weakened by osteoporosis — are the mainstay of treatment. In severe cases, surgery may be necessary.

CAUSES

Even after you’ve reached your full height, your bones don’t stop growing. Bone is living tissue engaged in a continual process of renewal. During this constant process called remodeling, old bone is removed and replaced by new bone. Paget’s disease of bone disrupts this process.

Early in the course of the disease, old bone starts breaking down faster than new bone can be built. Over time, your body responds by generating new bone at a faster than normal rate. This rapid remodeling produces bone that’s softer and weaker than normal bone, which can lead to bone pain, deformities and fractures.

Scientists haven’t identified a cause of Paget’s disease of bone, though they have discovered several genes that appear to be linked to the disorder.

Some scientists believe Paget’s is related to a viral infection in your bone cells that may be present for many years before problems appear. Hereditary factors seem to influence whether you’re susceptible to the disease.

SYMPTOMS

Most people who have Paget’s disease of bone experience no symptoms. When symptoms do occur, the most common complaint is bone pain. The disease may affect only one or two areas of your body or may be widespread. Your signs and symptoms, if any, will depend on the part of your body that’s affected, including:

• Pelvis. Paget’s disease of bone in the pelvis can cause hip pain.
• Skull. An overgrowth of bone in the skull can cause hearing loss or headaches.
• Spine. If your spine is affected, nerve roots can become compressed. This can cause pain, tingling and numbness in an arm or leg.
• Leg. As the bones weaken, they may bend — causing you to become bowlegged. Enlarged and misshapen bones in your legs can put extra stress on nearby joints, which may cause wear-and-tear arthritis in your knee or hip.

When to see a doctor

Talk to your doctor if you have:

• Pain in your bones and joints
• Tingling and weakness
• Bone deformities