In their efforts to better understand the nature of knee pain caused by osteoarthritis, researchers are setting their sights a bit higher — on the brain.
Osteoarthritis, a degenerative disease of the soft and bony tissues, is the most common type of arthritis, affecting weight-bearing joints that include the knee and hip.
The pain is unique, doctors say, because it can be so prolonged and difficult to manage.
“Even with the best pharmaceuticals we have, it’s very rare that we can completely relieve a person’s pain from osteoarthritis,” says Laurence A. Bradley, a professor of medicine with the University of Alabama, Birmingham’s division of clinical immunology and rheumatology. “That’s due in large part to the fact that there is tissue damage that occurs and damage to the joints.”
But Bradley suspects the brain may also play a big role in how people experience that pain, possibly creating a vicious cycle of sorts.
“There is evidence that people who experience prolonged periods of pain may become more sensitive to pain,” he says.
To investigate the possible link, Bradley and his colleagues are conducting a study in which pressure will first be applied to a person’s knees and then brain-imaging techniques will be used to observe any changes that may occur in the brain.
“By doing this study, we want to see if we can identify any pain alterations in some of the brain structures that both process pain and inhibit pain to see if there are changes in the function of these structures that differ from healthy people,” Bradley says.
“If we do see alterations in those functions, it would give us some clues that perhaps there is also a central nervous system component to the pain of knee osteoarthritis,” he adds.
Dr. Nicholas A. DiNubile, an orthopedic consultant for the Philadelphia 76ers basketball team, says that any research leading to a better understanding and alleviation of arthritis pain would be welcome.
“I see people every day who have to dramatically change their life and their lifestyle because of the pain associated with arthritis, and it can be any kind of arthritis. It’s in fact one of the leading causes of disability in this country,” he says.
DiNubile says treatment can run the gamut from medication, exercise, physical therapy and splints to surgery. “It really depends on the joint involved and how bad the symptoms are.”
The Arthritis Foundation reports that osteoarthritis affects more than 20 million Americans. Although it’s usually associated with aging, the disease is also linked to obesity and genetics.
What To Do
Read about how Exercise and Therapy Can Save Arthritic Knees in this HealthSCOUT story.
Visit the Arthritis Foundation for more information on the disease.