Paget Disease of Bone

Paget disease of the bone is a disorder that causes bones to become enlarged and misshapen, making them vulnerable to breaking easily (fractures).

The classic form of Paget disease of the bone typically appears in middle age or later. It usually occurs in one or a few bones and does not spread from one bone to another. The disease most commonly affects bones in the spine, pelvis, skull or legs.

The cause of Paget disease is unknown. It may be due to genetic factors or a viral infection early in life. The disease occurs worldwide, but is more commonly found in Europe, Australia, and New Zealand.


Many patients do not know they have Paget’s disease because they have no apparent symptoms.

Typical symptoms may include:

  • Pain
  • Headaches and hearing loss
  • Pressure on nerves
  • Increased head size, bowing of a limb or curvature of the spine
  • Hip pain
  • Damage to cartilage of joints

Any bone or bones can be affected, but Paget’s disease occurs most frequently in the spine, pelvis legs or skull. Generally, symptoms progress slowly and the disease does not spread to normal bones.

Diagnosis and Treatment

Paget’s disease is almost always diagnosed using X-rays but may be discovered initially by either of the following tests:

    • Alkaline phosphatase blood test: An elevated level of alkaline phosphatase in the blood can be suggestive of Paget’s disease.
    • Bone scans: Bone scans are useful in determining the extent and activity of the condition.
      Once a blood test or bone scan suggests Paget’s disease, the affected bones should be X-rayed to confirm the diagnosis.

Drug therapy helps prevent further bone breakdown and formation. Currently, there are several classes of drugs used to treat Paget disease. These include:

      • Bisphosphonates: These drugs are the first treatment, and they help decrease bone remodelling. Medicines are commonly taken by the mouth, but can also be given through a vein (intravenously).
      • Calcitonin: This hormone is involved in bone metabolism. It may be given as a nasal spray (Miacalcin) or as an injection under the skin (Calcimar or Mithracin).

Acetaminophen or non-steroidal anti-inflammatory drugs (NSAIDs) may also be given for pain. In severe cases, orthopedic surgery may be required.