Paget’s Disease of the Bone

Paget’s disease of the bone is a disorder that interferes with the body’s recycling process of the new bone tissue replacing old bone tissue gradually. The disease usually occurs in the legs, pelvis, spine, and skull, and causes the diseased bones to become fragile and out of shape.

Risks for Paget’s disease of the bone includes age and genetics. Complications are broken bones, pinched nerve in the spine, and hearing loss. Medications are usually used to treat the disease, but in severe cases, surgery may be necessary.

Typically, people with Paget’s disease of the bone feel no symptoms. At times, however, symptoms usually involve bone pain.

The signs and symptoms generally depend on what part of the body is affected:

• Pelvis: If the pelvic area is affected, Paget’s disease of bone can cause hip pain.

• Skull: The disease cause a bone overgrowth in the skull, which causes headaches and hearing loss.

• Spine: If the spine is affected, nerve root compression may occur, causing pain and numbness in the arm or leg.

• Leg:The affected leg will have weakened bones, which may bend and cause bowleggedness. Misshapen and enlarged bones in the legs also put stress on the joints and may cause knee or hip osteoarthritis.

The exact cause of Paget’s disease of the bone is still unknown. However, scientists suspect that Paget’s disease of bone may be caused by the combination of genetic and environmental factors.

There are also theories that the disease is an effect of a certain viral infection, but the theory is still controversial.

Making a diagnosis of Paget’s disease of the bone is done by performing several tests.

You are more likely to undergo a physical examination that involves checking the parts of your body that are painful. Imaging tests and laboratory exams are usually done, as well.

Imaging tests that are usually used to reveal bone changes that occur with Paget’s disease of bone include:

• X-rays: Abnormalities on the bone found on X-rays are often the first indication of Paget’s disease of bone. X-ray scans can show enlargement of the bone, deformities, and bone reabsorption, which characterize the disease.
• Bone scan: This involves injecting radioactive material into the body . The radioactive substance then travels to the spots on the diseased bones, which light up on the images.
• Laboratory tests: High levels of alkaline phosphatase in the blood are very usual in people with Paget’s disease of bone.

In rare cases when you do not have symptoms of Paget’s disease of the bone, treatment may not be needed. However, if the disease is active, which is indicated by the elevated level of alkaline phosphatase, and affects high-risk parts of the body like the spine or skull, treatment may be given to prevent further complications.

Medications

Bisphosphonates or osteoporosis drugs are the most common medications used in treating Paget’s disease of bone. While some bisphosphonates are taken orally, others are administered through injection. Examples of bisphosphonates are:

• Alendronate
• Ibandronate
• Pamidronate
• Risedronate
• Zoledronic acid

While effective in treating Paget’s disease of bone, bisphosphonates are linked to side effects like severe pain in the muscles, joints, and bones. The drug can also increase the risk of having a rare condition called osteonecrosis of the jawbone.

If bisphosphonates cannot be tolerated, calcitonin may be prescribed. It is a drug that is administered as a nasal spray or by injection. Side effects of this drug may include facial flushing, nausea, and irritation at the site of injection.

Surgery

In severe cases, surgery may be needed to heal fractured bones, replace damaged joints, realign deformed bones, or reduce pressure on the nerves.

There are several risks and complications associated with Paget’s disease of the bone.

The risk factors for PAget’s disease of bones include:

• Sex- Men have more tendency of having the disease compared to women.
• Age- People aged 40 and up are more at risk of having Paget’s disease of bone.
• National origin- The disease is more common in Central Europe, Greece, England, and Scotland; and is very rare in Asia and Scandinavia.
• Family history- You have a higher risk for the disease if you have a close relative who has it.

Most cases of the disease can be managed effectively using the available treatment methods. However, it is still possible to get some complications, such as:

• Fractures and deformities- The diseased bones tend to break easily, the bones of the legs can bow, affecting the ability to walk.
• Osteoarthritis- Osteoarthritis may take place with increased amount of stress on the nearby joints of misshapen bones.
• Heart failure- In severe cases, the heart is forced to work harder in supplying blood to the affected parts of the body. This can lead to heart failure in people who have pre-existing heart disease.
• Bone cancer- Less than 1 per cent of people with Paget’s disease of bone have bone cancer.