As a last resort, total knee replacement is an effective way to treat knee pain and increase independence in older adults, even when that pain is caused by advanced osteoarthritis, according to research presented at a recent meeting of the American College of Rheumatology.
However, knee replacement is just one of many options from which to choose, depending on the cause of the pain, the severity of the condition, and the individual. You may not be able to totally eliminate knee pain, but you have plenty of weapons to reduce the discomfort enough to carry on normal daily activities.
Today, a variety of effective interventions are available for persistent knee problems, and many of these can greatly improve pain, mobility, and quality of life. Talk with your doctor about which of the following strategies will work well for you:
1) Nonsteroidal anti-inflammatory drugs (NSAIDs). Over-the-counter NSAIDs such as ibuprofen (Alaxan, Advil, Motrin) and naproxen (Skelan, Aleve) can be used independently or combined with other treatments. NSAIDs are effective for mild and moderate pain, but there is a limit to how much discomfort they can control. Side effects, even with normally recommended doses, can include stomach pain, nausea, bleeding, or ulcers. Large doses and long-term use can lead to gastric bleeding or kidney problems.
2) Other analgesics. Acetaminophen (Tylenol) has been shown to be just as effective for pain as NSAIDs, but without the risk of gastric bleeding or kidney problems. For this reason, acetaminophen has become the drug of choice for many patients with persistent knee pain that is mild or moderate in severity. For more severe pain, the alternative is usually narcotic, such as codeine, synthetic codeines, or derivatives of morphine. Because of well-known side effects, these drugs are not for everyone and should be carefully limited.
3) Topical analgesics. Almost all pain-relief medicines that you rub into the skin are available without prescription. They act on local nerve endings and are best for temporary localized knee pain relief. Some of the products distract you from the underlying pain, while others actually help block the transmission of pain signals. Many contain an active ingredient called capsaicin (a compound that causes the “heat” in chili peppers), which can cause an irritating, burning sensation if not used correctly.
Topical analgesics are not a cure, but a promising source of short-term relief. Among older patients with osteoarthritis, a Yale University survey found that capsaicin creams were preferred over oral NSAIDs and other treatments for knee pain — not because they are more effective, but because they do not carry the risk of gastrointestinal side effects.
4) Weight loss. If you are among the increasing number of people who are either overweight or obese, losing weight might be the best pain-relief strategy of all. A study published in Arthritis and Rheumatism in July 2005 found that every pound lost results in a four-pound reduction in pressure exerted on knee joints. With every step taken, the cumulative amount of pressure becomes significant. Less pressure equals less wear and tear, and consequently, less pain. The study did not show that weight loss slows progression of osteoarthritis, but it implies that weight loss should be used as a treatment.
5) Exercise. Among conservative treatments for knee pains, exercise — in or out of a supervised physical therapy program – should be high on your list (see picture). A study in the October 2007 issue of Arthritis Care & Research supports the pain-relieving benefits of exercise for older adults. The data suggest that “at least 20 minutes of exercise once a week that is sufficient enough to result in sweating or some shortness of breath might be adequate for pain relief.”
According to the American Geriatrics Society, randomized, controlled trials clearly show that regular moderate-level exercise neither makes osteoarthritis pain worse nor does it accelerate the disease process. These studies also “strongly indicate” that increasing the level of physical activity in osteoarthritis patients reduces pain and morbidity.
6) Viscosupplementation. Another alternative to treating knee pain caused by osteoarthritis is viscosupplementation, which involves the injection of a thick lubricating substance called hyaluronate. It is a natural component of healthy joints, but people with osteoarthritis have it in low concentrations.
“The best candidates for viscosupplementation are people who have mild to moderate osteoarthritis, but the treatment can also be effective in severe cases,” says David Fish, MD, a specialist in physical medicine and rehabilitation at the UCLA School of Medicine. “These people may not be ready for surgery and they want to maximize all of their conservative options.”
Knee injections are a temporary solution to a long-term problem. They won’t work for everyone, but the treatment is worth discussing with your doctor. Studies endorsed by the US Food and Drug Administration (FDA) found that hyaluronate provides relief for up to six months.
Infection at the injection site is possible, but not likely. Commonly reported side effects include pain at the injection site, swelling, heat, redness, itching, and bruising. Reactions are usually mild and temporary, and applying an ice pack will ease the discomfort.
7) Cartilage transplant. It is now possible to transplant cartilage from a healthy, non-weight-bearing area of the knee to a damaged area. This technique works best when it is performed on a person with an otherwise healthy knee, but it is not a good option for advanced cases of osteoarthritis or rheumatoid arthritis.
Rehabilitation after cartilage transplant usually includes the use of crutches and limited weight-bearing activity for three to six weeks, depending on the size of the area affected. Total recovery could take at least four months, possibly longer.
The results of cartilage transplant vary widely, depending on the age and physical condition of the patient. Success is best measured by how well the person functions based on pre-surgery expectations.
8) Partial knee replacement. For people who have suffered significant damage but still have some degree of healthy knee cartilage, partial knee replacement (also called unicompartmental arthroplasty) may be an option. The surgeon replaces only the damaged areas of the knee. Healing usually takes a couple of months, but long-term results are not as good as total knee replacement.
9) Total knee replacement. In total knee replacement, an orthopedic surgeon removes damaged bone and cartilage and replaces them with artificial components made of metal, plastic, and polymers (see illustration). You may be a candidate for total joint replacement if your knee is severely damaged, if your mobility and function are diminished, and if you are older than 55.
New techniques, especially the minimally-invasive quad-sparing total knee replacement procedure, have made this type of surgery less traumatic than in the past. The incisions are smaller, the pain is much easier to tolerate, and the recovery time is faster. “We’ve become increasingly elegant in the way we do these surgeries,” says Daniel Oaks, MD, chief of the joint replacement service at the UCLA Medical Center and Orthopedic Hospital. “Our patients are going home sooner, with less discomfort and better results,” he adds.
What You Can Do
Here are some take-home messages if you have significant pain in your knee:
• If you are overweight, talk to your doctor or nutritionist about a weight-loss program to reduce knee pressure and relieve knee pain.
• Exercise (walk) at least 20 minutes once a week, “sufficient enough to result in sweating.” Better still, exercise for 30 minutes, five to six days a week.
• If your knee pain is severe and long-lasting, ask your doctor about knee injections and surgical options.