Paget’s disease is a bone disorder that can result in enlarged and misshapen bones. The excessive breakdown and formation of bone tissue causes bones to weaken, fracture, and other bone and joint problems, including osteoarthritis. Paget’s disease typically affects just one -- and sometimes a few -- bones as opposed to osteoporosis, which affects all the bones in the body. The condition is very painful. Orthopedic specialists do not know for sure what causes Paget’s disease.
Not everyone with Paget’s disease will develop osteoarthritis. Few people, unfortunately, develop both conditions but they are unrelated. Both Paget’s disease and osteoarthritis can cause joint and bone pain. In people with both conditions, joint and bone pain can occur in the same areas of the body. This can sometimes make it difficult for orthopedic surgeons to tell which condition is causing the pain.
The diagnosis of osteoarthritis in a person with Paget’s disease may involve blood tests, x-ray images, or the examination of fluid drawn from the joint. Blood and urine tests may also be used to help find out if something other than Paget’s disease is causing the arthritis.
The bone changes revealed by x-ray images help the orthopedic surgeon diagnose both osteoarthritis and Paget’s disease. However, in people who have both conditions in the same area of the body, it is often difficult to distinguish between the two.
In patients who do have symptoms, bone pain is the most common complaint. This pain can be related to active Paget's disease or to its complications, which include:
- Fractures due to brittle bone.
- Deformity of bone, including bowing of the affected bone.
- Advanced arthritis in joints near the affected bone.
- Compression on neighboring nerves from enlarged bones, leading to a loss of sensation or movement.
The cause of Paget’s disease is not known, but doctors have identified a number of risk factors that make someone more likely to develop the disease. These include:
- Genetics. Paget’s disease tends to run in families. In as many as 25 to 40 percent of cases, another relative will also have the disease.
- Age. Paget's disease occurs only rarely in people under 40 years of age. It is more common as people age.
- Ancestry. It is more common in people of Anglo-Saxon descent and those who live in certain geographic areas, such as the United States, England, Australia, New Zealand, and Western Europe. It is not common in Scandinavia, China, Japan, or India.
- Environmental factors. Some studies suggest that certain environmental exposures may play a role in the development of Paget's disease. This has not been proven definitively, however.
While there are no known ways to prevent Paget's disease from occurring, eating a healthy diet with sufficient calcium and vitamin D, and getting regular exercise, are important components in maintaining skeletal health and joint mobility.
There is no cure for Paget’s disease and no way to reverse its effects on bone. Treatment focuses on relieving symptoms and preventing future complications.
If you do not have pain or other symptoms, no treatment is required. Our orthopedic surgeon may recommend simply monitoring your condition with regular office visits and periodic x-rays to watch for changes in the affected bone and to ensure that complications do not develop.
If symptoms do occur, your doctor may recommend one or more nonsurgical treatments.
Anti-inflammatory drugs Medications such as ibuprofen and aspirin can help relieve mild bone pain that arises from Paget’s disease or from arthritis that may be associated with the disease.
Assistive devices. If your pelvis or leg is affected by the disease, using a cane can help relieve pain by decreasing the forces going through the bone. Using a cane can also help prevent falls, so there is less risk of fracture in the bone—a common complication of Paget’s disease. Wearing a brace can help relieve pain by preventing malalignment of the affected bones.
In some cases, surgery may be needed to treat the complications of Paget's disease, including:
- Bone fractures
- Malalignment or deformity of bone
- Severe arthritis
The surgical procedures used to treat fractures, malalignment, or arthritis in patients with Paget's disease are similar to those used to treat similar conditions in people with normal bone.
These procedures may include:
- Internal fixation. This procedure can be used to treat fractures in bone affected by the disease. In internal fixation, bone fragments are first repositioned into their normal alignment, then held in place with screws, wires, pins, or metal plates attached to the outside of the bone.
- Osteotomy. An osteotomy can help relieve pain and restore alignment to weight-bearing joints that are affected by Paget’s disease, especially the knee and hip. During the procedure, your doctor will remove a wedge of bone near the damaged joint in order to shift weight onto a healthier part of the joint.
- Total joint replacement. In this procedure, parts of an arthritic or damaged joint are removed and replaced with a metal, plastic or ceramic device called a prosthesis. The prosthesis is designed to replicate the movement of a normal, healthy joint.
Surgery may also be needed if an enlarged bone begins to compress nerves, especially in the spine or skull. In the rare case of Paget's sarcoma, surgery is almost always used to try to remove the tumor entirely. Chemotherapy and radiation therapy may also be used.
Bones affected by Paget's disease may take longer to heal than normal bones. A longer period of rehabilitation may also be necessary.
If treatment occurs before major changes in bone occur, the majority of patients with Paget’s disease are able to live a normal, active life. When complications do develop, surgical treatment is usually effective in relieving pain and improving function.
Sources: NIH.org and AAOS.org. Diseases of the bone.