Just a bit of lube can fix a squeaky hinge or keep an engine running smoothly for thousands of miles. Nowadays, it can do the same for an arthritic knee.
Viscosupplementation, a relatively new treatment for osteoarthritis of the knee, transforms natural rooster comb into a high-tech “motor oil” that can relieve joint pain and delay or even prevent surgery.
Patients with osteoarthritis, also known as degenerative joint disease, typically have a reduced amount of the shock-absorbing substance hyaluronan in their synovial, or joint fluid. Without sufficient hyaluronan, joint fluid loses its viscous quality and may cause increased friction, joint pain and loss of mobility.
Although hyaluronan is present in all vertebrates, rooster’s comb — the red swath on the top of a rooster’s head — is an especially rich and plentiful source.
“The theory is if you stick rooster comb extract into a patient’s knee, it’s like putting more lube in the knee,” said Sara Walker, an MU professor of internal medicine.
Conservative treatments for osteoarthritis of the knee include simple lifestyle changes such as losing weight or strengthening leg muscles. Other options include small doses of over-the-counter drugs such as Tylenol and Naproxen, the nutritional supplement glucosamine or steroid injections. If these measures proved ineffective in the past, Walker said, a patient was essentially left with only two options: live with the pain, or have surgery to repair or completely replace the knee joint.
Now, thanks to the roosters, a third option is available — lube the joint with a hyaluronan product and hope it alleviates some pain.
“To other people, osteoarthritis doesn’t seem like a big deal,” Walker said. “But people who get it have pain every time they try to take a step. That’s horrible. So this makes a lot of sense.”
Viscosupplementation is not a cure, Walker said, but simply a treatment that might temporarily abate arthritis-related pain and improve knee function. A dose is administered in three to five consecutive weekly injections, and the effects can last several months.
In 1997, the federal Food and Drug Administration cleared viscosupplementation, classifying it as a device rather than a drug. Since then, millions of arthritis sufferers have received the injections.
“People are generally enthusiastic about anything that holds the potential to help avoid surgery for as long as possible,” said Brad Ziegler, president of the Missouri chapter of the Arthritis Foundation. The foundation provides area residents with a variety of educational programs, including a surgical alternatives session that gives information about viscosupplementation.
Herb Parham, 87, has been getting the injections regularly for several years. Before he began the treatment, Parham’s knee problems were getting worse, and he was not able to walk without support. He said his knee performance has gradually improved since he started getting the injections, and he is now able to walk unaided.
“Thus far, it’s showing good promise,” said Parham. “I don’t think I’m going to need a knee replacement.”
Not all patients see such improvements. Parham said several of his friends have received the same treatment and seen no results.
“No one thing is going to work for everybody,” Ziegler said.
While the effects of viscosupplementaion are still not proved, Walker said about two-thirds of her patients have gotten pain relief from the treatment. One study by the American Academy of Orthopaedic Surgeons found that up to 75 percent of patients have been able to delay knee-replacement surgery after receiving one brand of the injections.
Another study presented at an annual meeting of the Academy, however, found the treatment to be no more effective than the more traditional and significantly cheaper steroid shots. Viscosupplementation is covered by many major medical insurance plans. The cost of a full dose of three to five injections varies among brands and often exceeds $500.
Walker said the treatment’s effectiveness might depend on the extent of cartilage damage in the osteoarthritic knee and the patient’s weight, which can compress the knee.
“It really varies with the patient,” she said. “Some people can have pretty serious disease, but they’re still able to function. Other people get to the point that their quality of life is pretty bad. Most people know when they’re ready for surgery.”
In addition to the products made from hyaluronan extracted from rooster’s comb, artificially manufactured hyaluronan-based products made from bacteria cultures are available. Hyaluronan can be used in other medical applications, such as protecting the eye during surgery and preventing post-surgery scar tissue, and recently it has been hailed for its cosmetic benefits, such as filling in wrinkles.