Time to replace that joint?

At the age of 63, Mary Barrett got a chance at a new life. For the first time in months, she was able to do the things she wanted to do, to move around without help and without the crippling pain that had become a constant part of her life. And what made it all possible was a highly engineered device of metal and plastic: a new knee.

Barrett, now 84, is one of a growing number of Canadians benefiting from knee and hip replacements – operations doctors say have a bigger impact on the quality of life than just about any other medical procedure. The newest figures available show that in the five years ending in 2000, the number of total hip replacements performed in Canada rose more than 19 per cent to 20,036 operations. Knee replacements shot up much faster in the same period, hitting 22,302 procedures — an increase of 45 per cent in five years.

Why the dramatic increase in joint replacement?
Part of the reason for the increase is the aging population. Joints typically start to show wear when people are in their 50s and 60s. The Canadian Institute for Health Information (CIHI) says of total hip and knee replacements performed in 1999-2000, 89er cent were for people aged 55 and older.

And the boomers have reached an age when replacements are an attractive option. Their passion for exercise has also contributed to the increase in number of joint replacements. “We wouldn’t expect knee replacements to increase 45 per cent because of the aging population alone,” says Julian Martalog, a consultant to the CIHI. He says old sports injuries and years of joint-pounding activities, such as jogging, are probably factors.

Replacement demand is up
There’s also increased patient demand, says Dr. Jeffrey Gollish, an orthopedic surgeon and head of arthroplasty services at the Orthopedic and Arthritic Hospital at Sunnybrook and Women’s College Health Sciences Centre in Toronto. The success rates are so high — about 90 per cent satisfaction for hip replacements and more than 80 per cent for knees — that many patients are demanding the procedure even without a doctor’s recommendation. “We’re seeing a lot of younger patients and a lot more older patients that we might not have considered in the past,” he says. Gollish says patients in their 90s are now asking for replacement operations rather than spend their lives in wheelchairs.

Although the numbers are on the rise, replacements are still relatively new. Hip replacements only started becoming a popular choice in the 1970s. The more complex knee replacements had a troubled history and a high failure rate until the last 10 to 15 years.

Why good joints go bad
Here’s how joints deteriorate. The ends of the bones that meet at any joint in the body are covered with a layer of slippery white tissue called cartilage. It absorbs impact and lets the bones glide smoothly over each other.
Over time, cartilage can start to deteriorate.

In about 90 per cent of cases, the deterioration is the result of long-term wear called osteoarthritis. It’s not clear why it happens to some people and not to others. Genetics probably play a role. Sometimes, an injury that hasn’t healed properly or that has pushed the joints out of alignment is a factor. In about 10 per cent of cases, the wear is caused by rheumatoid arthritis. In this type of arthritis, the body attacks its own cartilage, causing inflammation, which in turn leads to cartilage damage. In either case, when the cartilage wears away, the ends of the bone rub against each other, causing pain and, in some cases, deformity.

Next page: That old ounce of prevention

That old ounce of prevention
Once the deterioration starts, the body can’t repair the damage. “It’s a relentlessly progressive problem for which we have no cure,” says Gollish. But there are things you can do to extend the life of your natural joints. The single biggest factor is losing weight. Excess weight stresses the joints, increasing wear. Exercise is also important. Strengthening the muscles around a joint not only helps reduce wear but also speeds recovery if a replacement operation becomes necessary. But it has to be the right kind of exercise. If you experience pain or swelling of the joints after a workout, eliminate high-impact activities such as jogging or step aerobics.

“There’s lots of evidence that impact is harder on the lower joints than a gliding motion,” says Dr. Cyril Frank, a professor of orthopedic surgery with a special interest in sports injuries at the University of Calgary. Frank says activities such as cross-country skiing, cycling and swimming are good choices. If you do chose high-impact exercises, such as jogging, it’s important to do them properly: build up slowly; start with stretching exercises; wear good shoes with proper arch support; and try to use a gliding motion when you run, rather than pounding the pavement.

Joint replacements can often be postponed using a new generation of anti-inflammatory drugs that don’t cause the same stomach upset as some of the older drugs.

The nuts and bolts of replacement
To replace joints, orthopedic surgeons cut away the ends of the affected bones and replace them with parts usually made from titanium or cobalt chrome metal. Glue is sometimes used to hold the metal ends in place. In many hip replacements, no glue is necessary because the bone cells will grow around the metal and hold it tight. Smooth plates of polyethylene plastic are usually fitted between the metal ends to take the place of cartilage.

In a total joint replacement, both sides of a joint are replaced. Sometimes, only one side is replaced, for instance, when someone breaks a hip. The ball at the top of the thighbone loses its blood supply and dies. Surgeons perform a partial replacement, fitting a new artificial ball on the leg bone and pushing it into the natural socket in the pelvis.

The role of exercise in recovery
As with any major operation, there is pain involved with joint replacements. But the pain from the operation is often less than that caused by a damaged joint. “I’ve had patients tell me the day after the operation that the constant pain they had had was gone,” says Dr. Gianni Maistrelli, chief of orthopedic surgery at the Toronto East General and Orthopedic Hospital. Most patients are on their feet with help within a day of the operation and can get around for short distances with a walker in a few days. Healing takes about six weeks, and most patients recover 80 per cent of their function within a year.

Mary Kim had her first replacement operation at 30 when she got two new knees. Kim, now 42, suffers from severe rheumatoid arthritis. Since that first operation, she has had both hips, both shoulders and an elbow replaced. Kim, a volunteer with the Arthritis Society in Toronto, says she has seen great advances in post-operative physiotherapy and especially in pain control over the years. She says key factors in a successful recovery are exercising and following as healthy a lifestyle as possible before going into the operating room. “The healthier you are before the operation, the faster the recovery,” she says.

But full recovery depends on the patient. It’s vital to do regular exercises prescribed by a physiotherapist, especially in the first six weeks after surgery. And it’s important to avoid heavy impact on the joints. “There are patients who feel so good they go back to skiing or tennis right away,” says Maistrelli, “but that’s not recommended.”

Next page: Be realistic

Be realistic about replacement
While replacement operations are generally very successful, they are not perfect. About 10 per cent of patients report being unhappy with the outcome. In about one out of 10 of those cases, the problem is a complication such as infection or dislocation of the new joint. But the biggest source of dissatisfaction, says Gollish, is an unrealistic expectation about how pain-free and mobile the patient will be. Most people can expect their joint pain to be reduced about 80 per cent by the operation but he cautions, “You’re not going to be 20 years old again.

There can also be unexpected problems. Paul Brownstein had an operation in 2001 to replace his left knee, damaged by playing football many years ago. The 62-year-old from Thornhill, Ont., suffered from sciatica, a shooting pain in his right leg. His posture, thrown off by his bad knee, put extra pressure on a disc in his back, irritating the major sciatic nerve running down his right leg. Brownstein hoped the knee operation would fix that problem by aligning his posture but instead it got worse. A small operation on his back stopped the leg pain. Despite the setback, Brownstein is enthusiastic about replacements. “Right now, I’m as happy as one can be,” he says. “I’m pain-free for the first time in years.”

Playing the numbers game
The reality is even artificial joints eventually wear out. The average amount of walking puts joints through about a million back-and-forth cycles a year. About 90 per cent of artificial knees will last 10 years. Most hips survive about 15 years. Wear rates are higher among patients under 55 simply because they tend to be more active than older people. Often, it’s the plastic lining of the joint that wears out. Replacing it is a simpler procedure than the original operation, and recovery times are much shorter. A new generation of plastic that appeared about three years ago shows promise in extending the life of artificial joints by many years.

The greatest obstacle
But joint replacement operations are becoming a victim of their own popularity. Waiting lists are at crisis levels. According to the Fraser Institute, the average wait for orthopedic surgery in 2002 was 32 weeks from the time a family doctor refers the patient to a specialist until the operation. That’s longer than for any other type of surgery — and up substantially from the 19.5-week wait in 1994. The reasons for the increase? Fewer doctors are going into the specialty, partly because it involves heavy physical effort and brutal working hours. It’s estimated that Canada needs almost 200 more orthopedic specialists immediately.

At the same time, hospitals facing budget constraints are reluctant to put more resources into orthopedic departments. As a result, surgeons can’t get enough access to anesthetists, hospital beds or equipment. Yet, according to the Institute of Health Economics, osteoarthritis is two and a half times more prevalent in Canada than heart disease.

Gollish says he doesn’t see the situation getting any better unless ordinary people start pressuring politicians to come up with more money. “There’s no short-term solution for this,” he says. “People out there can make the difference.” In the meantime, he says, the best advice is to ask your doctor for a referral when joint pain starts to intrude on your life. “Get a referral when you still have moderate arthritis,” he says. “Don’t wait until you need crutches.”