Performing hip and knee replacements to treat severe arthritis saves the health system money in addition to relieving the pain of most sufferers, new Canadian research shows.
But the study, published in today's edition of the journal Medical Care, also suggests that there should be more careful selection of patients who receive joint replacements to maximize both the medical and economic benefits.
Gillian Hawker, chief of medicine at Women's College Hospital in Toronto and the principal investigator, said the study is the first to examine not only the cost of hip and knee replacements, but the cost of not offering surgery to patients with severe arthritis.
"The cost of not providing joint replacement is significant. These patients get significantly worse in terms of pain and disability and they incur significant medical costs," Dr. Hawker said in an interview.
The study involved 183 patients in Ontario who received joint replacement surgery and 183 others with a similar health profile who did not get a new hip or knee. The patients were, on average, age 71, and principally female, as most osteoarthritis sufferers are older women.
Patients who had surgery saw their arthritis-related pain diminish and their treatment costs (calculated over a 30-week window before and after surgery) fell, on average, $244 in the months after the operation. Those who did not have a joint replacement, meanwhile, saw their pain scores rise steadily and their arthritis-related health costs jumped $1,738 on average over the same time frame.
Dr. Hawker said that while those savings and costs seem modest, on a population level, they are significant.
"There are very few surgical interventions that actually save the health system money, but joint replacement does," she said.
Joint replacement operations cost, on average, a little less than $13,000 each, according to the research.
But the paper notes that there is wide variability in arthritis-related treatment costs both before and after surgery.
The research team also found that as many as one in five patients does not see noticeable improvements after joint replacement surgery.
In recent years, there has been a big push, as part of the wait times strategy, to shorten waits for hip and knee replacements, as well as to bolster the number of operations performed.
In 2005, there were 33,590 knee replacement and 25,124 hip replacement procedures performed in Canada, according to the Canadian Institute for Health Information. That is almost double the number performed a decade earlier and, in recent years, the numbers have continued to climb.
Dr. Hawker said there "remains a huge unmet need for joint replacement" in Canada but, instead of merely pushing more patients to surgery, physicians need to learn to focus on those who will have the best outcomes.
"We need to find the sweet spot - the time when we should be intervening that most benefits the patient and is most cost-effective," she said.
The new study suggests that this is at a time when a patient has significant pain from arthritis but has not yet deteriorated to the point where they are disabled by the lack of function in their joints.
More than four million Canadians have some form of arthritis and two-thirds of those affected are women, according to the Canadian Arthritis Network.
The term arthritis includes more than 100 diseases and conditions, but osteoarthritis - caused by a breakdown of cartilage in the joints - is the most common form, affecting one in 10 adult Canadians.
As the cartilage wears and breaks away, the joint fails to move smoothly, resulting in pain. Osteoarthritis can occur in any joint in the body but most commonly affects the fingers, knees, hips and spine.