As reported by The Hartford Courant, May 17, 2005.
Putting a Needle Where It Hurts
By Garret Condon
Way back in 2004, lots of people with sore knees because of osteoarthritis reached for Vioxx and Bextra and other non-steroidal anti-inflammatory drugs. Popping a pill for pain sounded much better than getting an injection, explains Dr. Carl Nissen, associate professor of orthopedics at the University of Connecticut Health Center.
Now that Vioxx and Bextra have been pulled off the shelves, that needle is starting to look good.
"Maybe people were squeamish about getting an injection," he said. "Now they're being a little more forward and saying, `Hey, I'd like that injection now.'"
They know the next step may be surgery, and, as Dr. Robert Green notes, "Nobody is in a hurry to get an operation." Green is chairman of the department of orthopedics at St. Francis Hospital and Medical Center.
The injection that patients are increasingly seeking is a kind of lube job for a creaky knee called viscosupplementation. Experts agree that it's not a cure-all, it's not for everyone and it's not even the first step for patients with mild pain. But for many people, it can help postpone surgery.
Joints are bathed in a thick liquid called synovial fluid that lubricates and feeds the cartilage and keeps it functional. In osteoarthritis, this fluid breaks down and loses some of its cushioning quality and viscosity - much as motor oil breaks down in an automobile.
The idea behind viscosupplementation is to replenish a key ingredient of this fluid - hyaluronic acid - as a way of relieving pain and improving function. In 1997, the federal Food and Drug Administration approved the first two of four currently available supplementation products for arthritic knees.
Patients get a weekly shot for three to five weeks, depending on the brand of supplement. Relief is not always instantaneous, but Nissen noted that a large Canadian study showed equal or better relief compared with drugs like Vioxx. Participants in the study experienced nine to 15 months of reduced pain and improved mobility.
The medical literature on viscosupplementation, however, is all over the place. Some studies found little or no effect, while others found significant improvement.
Dr. Christopher Lena, an orthopedist at Hartford Hospital, said patient selection appears to be one of the keys to success with the therapy. He noted that people allergic to chicken products shouldn't use viscosupplementation because hyaluronic acid in currently available products is extracted from chicken combs. (A hyaluronic acid supplement not derived from chickens has been approved by the FDA and will be available soon.)
Lena said he does not use it for patients with fluid build-up in the knee. Side effects from the procedure are rare, he said, but they include the possibility of an infection from the injection.
"I don't sell it as a panacea," he said. "It's a potential temporary measure."
Philip Band, a biochemist who is an assistant research professor at New York University School of Medicine and who worked for two decades on the use of hyaluronic acid for the treatment of arthritis, said the technique seems to work best on patients at an early stage of disease.
Although the supplements are approved only for knees, Nissen said doctors have used the preparations "off-label" on other joints. He said a national, multicenter trial on the use of hyaluronic acid in hip joints is underway.
While getting a knee-joint lube job may sound like a breeze, this procedure is not Square 1 for most patients. Doctors begin with the most conservative measures, such as the intermittent use of acetaminophen (Tylenol, for example) or one of the still-available non-steroidal anti-inflammatory drugs, like ibuprofen (Advil) or naproxen (Aleve). Green and Lena said they commonly suggest that patients try the dietary supplement glucosamine sulfate, which has been shown in some studies to improve the symptoms of osteoarthritis.
Other early approaches include bracing the joint with elastic sleeves or using heel wedges in shoes to shift the position of the knee joint.
If these moves don't work, the next step is corticosteroid injections, which can reduce inflammation. Nissen said he prefers to give no more than three or four shots in a single joint for the patient's lifetime because overuse can result in crystallization or deposits of the steroid and its additives within the cartilage. But he acknowledges that some doctors will administer three or four such injections a year.
Physicians are quick to add that there are important non-medical measures that patients can take, especially losing weight and staying physically active.
"The most common thing is for a patient to have pain and stop exercising," said Nissen. "But arthritis gets worse when you stop exercising." The trick is to find a form of exercise that doesn't hurt. A runner might switch to cycling or swimming, said Nissen. "The percentage of people who get better with that is high," he added.
Band notes that when viscosupplementation works, the relief it provides can make physical activity easier, creating a kind of upward spiral for the patient.
Ultimately, however, many arthritis patients will turn to surgery for relief. Green said some individuals with osteoarthritis can have good results with an operation called an osteotomy, which shifts the load from inner side (the most common side for osteoarthritis) to the outer side. Beyond that, there are half-joint and full-joint replacement procedures.