Pagets Disease of Bone Vs. Osteoarthritis
Pagets disease of bone and osteoarthritis are completely different disorders that share some of the same symptoms; namely, joint pain and bone pain.
What is Pagets Disease of Bone?
Pagets disease of bone is a chronic disorder that can result in enlarged and misshapen bones. The excessive breakdown and formation of bone tissue causes affected bone to weaken, resulting in pain, misshapen bones, fractures, and other bone and joint problems, including osteoarthritis. Pagets disease typically is localized, affecting just one or a few bones, as opposed to osteoporosis, for example, which affects all the bones in the body. Although Pagets disease and osteoporosis can occur in the same patient, they are also completely different disorders. Scientists do not know for sure what causes Pagets disease.
What is Osteoarthritis?
Osteoarthritis is a condition that causes changes in cartilage, the elastic tissue that cushions the joints. Healthy cartilage allows bones to glide over one another, while absorbing energy from the shock of physical movement. In osteoarthritis, the surface layer of cartilage breaks down and wears away. This allows bones under the cartilage to rub together, causing pain, swelling, and loss of motion of the joint.
Distinguishing Between Pagets Disease and Osteoarthritis
Not everyone with Pagets disease will develop osteoarthritis. Among those who have both, some may have osteoarthritis caused by the Pagets disease while others will simply have two unrelated conditions.
Both Pagets 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 doctors to tell which condition is causing the pain.
No single test can diagnose osteoarthritis. The diagnosis of osteoarthritis in a person with Pagets disease may include:
Blood and urine tests may also be used to help find out if something other than Pagets disease is causing the arthritis.
The bone changes revealed by x-ray images help doctors diagnose both osteoarthritis and Pagets disease. However, in people who have both conditions in the same area of the body, it can be difficult to distinguish between the two. For this reason, the judgment of the patients doctor is important for accurate diagnosis and effective treatment.
How Does Pagets Disease Cause Osteoarthritis?
Although they are different conditions, there is a link between Pagets disease and osteoarthritis. The changes that occur in bones affected by Pagets disease can also affect the function of nearby joints. As a result, people with Pagets disease frequently have osteoarthritis. Pagets disease can cause osteoarthritis when it:
What About Available Treatments?
The treatment strategies for Pagets disease and osteoarthritis are quite different, so it is important to distinguish between the two when making treatment-related decisions. For example, people with both disorders who get good results from their Pagets disease treatment may continue to experience arthritis-related pain. Correctly identifying osteoarthritis as the source of pain is critical to the selection of effective treatments.
The goal of osteoarthritis treatment is to improve joint function and control pain and swelling. Treatment approaches include:
The goal of Pagets disease treatment is to relieve pain and control the progress of the disorder. Treatment strategies include:
Because effective therapies are available for both Pagets disease and osteoarthritis, the results of the combination of the two disorders need not be severe. This is particularly true when treatment for Pagets disease begins before major complications have developed.
Related Resources
Source: Pagets Disease of Bone and Osteoarthritis: Different Yet Related (edited), NIAMS, Oct. 2005

