Susan Turner knew her full knee replacement was a success when she hopped on her bike and started pedalling down a Calgary street, feeling like she had a brand new lease on life.
It has been just over a year since she finally got off a long waiting list and had her arthritic left knee replaced with the latest metal and plastic version.
"I was a little apprehensive when I got on my bike last weekend, but it felt fabulous," says Ms. Turner, who won't give her age but describes herself as old enough to have worn-out knees.
"I had to use a cane for almost two years before the surgery and it made me feel 20 years older. The knee slowed me down, it hurt - you're just always aware of this impediment. Now, what an improvement."
Knees are the fulcra of our lives.
We depend on their integrity for our mobility, balance, grace and, for some, ability to perform.
Golf fans winced along with Tiger Woods every time he pivoted a bit too hard on his ravaged left knee during the recent U.S. Open, wondering whether the fragile joint would be the downfall of yet another sports legend.
Mr. Woods won the title, but it will be a year before fans see him playing on another golf course - time enough, he hopes, for the knee to recover.
"It is clear that the right thing to do is to listen to my doctors, follow through with this surgery, and focus my attention on rehabilitating my knee," Mr. Woods said in a statement.
It's unlikely knee replacement will be in the cards for Mr. Woods.
Although it's considered one of the most successful operations - ranking almost as high as cataract surgery - knee replacement remains a last-ditch procedure to improve the quality of life for people suffering from chronic pain and mobility issues.
"It's synthetic and essentially it doesn't feel quite like
a normal knee," said John Antoniou, a hip and knee surgeon at the Jewish Gen- eral Hospital in Montreal and a professor at McGill University.
"With knee replacement surgery, unfortunately, the level of function is not quite there and I don't think Tiger Woods would be anywhere near the top of his game if he had knee replacement surgery."
Ms. Turner agrees that the artificial knee doesn't feel like the natural joint.
She says that immediately after the surgery and during the early months of rehabilitation, the mechanism felt strange.
"You feel like you have something foreign in your body," she says.
"You can feel it and initially it is sort of uncomfortable and you'd rather it not feel like that. It doesn't hurt, but it feels bizarre. However, I'm used to the feeling now, and it's much more a part of me."
Ms. Turner's advice to physicians is to make sure patients are aware of the importance of the first weeks of physiotherapy and the need to quickly get the new knee bending at least 90 degrees.
She says she was dismayed when she went for a two-month checkup after her surgery and her doctor told her she wasn't doing well and may need another operation to force the knee to bend 90 degrees.
"He said, 'Right now I'm booking an operating room for three weeks down the road. I will see you in two weeks and if it's not bending 90 degrees, you're going back on the operating table and I will bend it for you.' That scared me. ... I started pushing and when I went back two weeks later, I was beyond 90 degrees."
According to the Canadian Institute for Health Information, there were 40,701 hospitalizations for knee replacements in 2005-2006.
That represents a 100-per-cent increase over the past 10 years, underscoring the fact that bone and joint problems are the No. 1 quality of life issue for Canadians.
The majority of Canadians receiving knee replacements are 55 years of age or older, but Dr. Antoniou says the fastest growing subpopulation is the 45 to 54 age bracket.
"There has been almost a threefold increase in the last 10 years in that age group," he says.
"It's primarily related to obesity ... Unfortunately, the implants aren't built to last forever and - especially in younger people where they're going to put the implants through their paces - it's going to lead to a lot of failures. That's a dilemma we have."
Dr. Antoniou says active people have an easier time adjusting to hip replacements than knee replacements, a reflection on the basic mechanics of the two joints.
While the hip is a fairly simple ball and socket joint, the knee is a complex hinge joint capable of bending, straightening and about 10 degrees of rotation inward and outward.
Arthritis is the main culprit in driving people onto waiting lists for the elective surgery, and Dr. Antoniou says the numbers will keep growing given today's lifestyles and the aging population.
"It seems the population is changing and one of the things we're fighting as a society now is, of course, obesity, and one of the consequences of that is a higher incidence of osteoarthritis," he says.