Paget's Disease of Bone

Overview

Paget's disease of bone is a chronic condition that interferes with the body's normal process of replacing old bone with new bone. Normally, bone is constantly broken down and rebuilt in a balanced cycle. In Paget's disease, this process becomes overactive and disorganized in certain bones, so new bone forms too quickly and is larger, softer, and weaker than normal.

The disease often affects the pelvis, spine, skull, and leg bones, and it may involve one bone or several. Many people have no symptoms and are diagnosed by chance during tests for another reason. When symptoms do occur, they can include bone pain, deformity, and a higher risk of fractures. Effective treatments are available to control the disease.

Symptoms

Many people with Paget's disease have no symptoms. When symptoms occur, they depend on which bones are affected and may include:

• Bone pain, which is often deep, aching, and constant
• Enlarged or misshapen bones, such as bowing of a leg or an increase in head size
• Joint pain or arthritis if affected bone is near a joint
• Increased warmth over the affected bone
• Fractures from weakened bone
• If the skull is involved, headaches or hearing loss
• If the spine is involved, nerve compression causing numbness, tingling, or weakness

Causes

The exact cause of Paget's disease is not fully understood. It is thought to result from a combination of genetic factors and possibly an environmental trigger such as a viral infection earlier in life, though this is not proven.

The disease tends to run in families, and several genes have been linked to it, so heredity plays an important role. The end result is overactive bone cells that break down and rebuild bone in a rapid, disorganized way, producing the larger but weaker bone that characterizes the condition.

Risk Factors

• Age over 50, with risk increasing further with age
• A family history of Paget's disease
• Northern European ancestry, where the condition is more common
• Male sex, as it occurs slightly more often in men

Paget's disease is not caused by diet, activity level, or calcium intake; the main factors are age and heredity.

Diagnosis

Paget's disease is often discovered incidentally on tests done for other reasons. Diagnosis involves:

• X-rays: Show the characteristic enlarged, thickened, and abnormally structured bone.
• Blood tests: A raised level of an enzyme called alkaline phosphatase reflects the increased bone activity.
• Bone scan: Highlights which bones are affected and how extensively.
• Additional imaging: CT or MRI if complications such as nerve compression are suspected.

Treatment

Treatment aims to control the overactive bone process, relieve symptoms, and prevent complications. Not everyone needs treatment, especially if there are no symptoms and the affected bones are low-risk.

• Bisphosphonate medications: The main treatment, these drugs slow the abnormal bone turnover and can relieve pain and stabilize the bone.
• Pain relief: Anti-inflammatory or other pain medications to manage discomfort.
• Supportive care: Calcium and vitamin D to support bone health, and physical therapy or supportive devices for affected joints.
• Surgery: Occasionally needed for severe deformity, fractures, severe arthritis, or to relieve pressure on nerves.

With treatment and monitoring, most people manage the condition well.

Prevention

There is no known way to prevent Paget's disease, since it is largely driven by genetics and age. However, some steps support bone health and reduce complications:

• Get enough calcium and vitamin D for general bone health
• Stay physically active to maintain strength and joint function, following your doctor's advice
• Prevent falls to reduce fracture risk
• Attend regular follow-up so the disease can be monitored and treated
• If Paget's disease runs in your family, discuss screening with your doctor

When to See a Doctor

See a doctor if you have persistent, unexplained bone or joint pain, notice that a bone seems enlarged or misshapen, or develop new hearing loss or headaches, especially if you are over 50. These can be signs of Paget's disease.

Seek prompt care if you experience a fracture, sudden severe pain, or new numbness, tingling, or weakness, which may indicate a complication such as a broken bone or nerve compression.

Related Topics

Frequently Asked Questions

References

1. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Paget's Disease of Bone.
2. Mayo Clinic. Paget's disease of bone — Symptoms and causes.
3. MedlinePlus, U.S. National Library of Medicine. Paget disease of the bone.
4. The Paget's Association.