Ouch: Baby Boomers’ Knees Reach Middle Age

The "baby boom" generation born between 1946 and 1964 is discovering middle age, and along with it knee problems made worse (or at least more obvious) by lifestyles that stay vigorous well into the later years.

There are nearly 77 million baby boomers, and a large number of them are trying to reconcile their desire to stay active with the fact that they’re starting to see the onset of conditions that affect their knees and other joints.

"Certainly the population in general is more active, and I think it’s starting in childhood," says Carole S. Vetter, MD, Medical College of Wisconsin Assistant Professor of Orthopaedic Surgery. "All these kids got involved in sports at much younger ages than they ever did before, and that translates into wanting to have an active lifestyle throughout their lives. They’ve been active, and semi-abusive to their knees, starting at a much younger age."

As people in the US continue to run, bike, shoot jump shots, hit softballs and stroke forehands, the National Institutes of Health estimates that up to 70 million of us have arthritis. The American Academy of Orthopaedic Surgeons says that about 4.1 million people seek medical care for knee problems and more than 450,000 knee and hip replacements are performed each year.

"We have more to offer people than we ever did," said Dr. Vetter. "If you were a farmer years ago you’d say ‘oh, my knee hurts, but that’s OK.’ You just dealt with it. Now we have a lot of interventions so people are saying ‘my knee hurts, but I think something can be done about it.’"

Wearing and Tearing
Knee problems can start with anything from osteoarthritis to traumatic injuries such as torn ligaments or cartilage damage caused by a sudden twist in a basketball game.

"Heading in to middle age, you may start to really notice the onset of osteoarthritis," said Dr. Vetter. "I always think of osteoarthritis as the ‘wear and tear’ arthritis. Certain individuals wear out their cartilage very quickly, whether that is from genetics or from trauma. Some people wear it out at a slower rate; some will reach 80 or 90 years old and have normal knees because they have harder cartilage or more shock-absorbing cartilage. We certainly see people up into their 70s and 80s who have pretty normal knees."

Cartilage is important to knee health because it serves as a cushion within the joint. Body tissue generally gets nutrients from the bloodstream, but cartilage is different. Cartilage feeds on a substance in the joints called synovial fluid. Regular exercise helps the body to make more synovial fluid and moves the fluid in the joint so that cartilage gets the oxygen and other nutrients it needs. One of the "tricks" to maintaining sound knees is to give them the exercise they require to function well and stay limber, while not overdoing it.

A critical piece of cartilage in the knee is the meniscus. "Meniscus tears are pretty common," said Dr. Vetter. "I would say the majority of meniscus tears I take care of are in people between 30 and 60 years old. It can be a 30-year-old who was squatting down or twisting during an activity. Or, as we get into the 60s, it’s more that the cartilage becomes a little brittle and it doesn’t take much to tear it. That’s an easy thing to take care of because a minimally invasive surgery will get rid of the problem. The most common surgery I do is the arthroscopy for meniscus tears."

Stay Away from a Handful of Harmful Activities
"Knee conditions that don’t require surgery usually involve anterior knee pain," said Dr. Vetter. "The patella (kneecap) starts to hurt. There might be a little bit of arthritis of the patella, but you can have normal cartilage on the patella and still have anterior knee pain." This kind of pain can slow people down and keep them from being as active as they’d like.

Non-surgical treatment options for knee problems include physical therapy incorporating specific exercises and stretches, and the use of anti-inflammatory medications that come in a wide range of categories. Trial and error is often necessary to find out which anti-inflammatory provides the best relief, Dr. Vetter said.

Other than traumatic injury, Dr. Vetter notes, very few activities are actually harmful to the knees. "Even with running, with all the pounding up and down, there is not a single study that shows running is particularly damaging to the knees," she says. "As long as you’re keeping active and keeping your legs healthy and strong, and you’re doing that by running, that’s fine.

Unfortunately, she added, "the kneecap is really a bad system" in terms of being able to handle certain kinds of pressure. Dr. Vetter cautioned against using stairs as part of an exercise regimen and against using knee extension machines that place weight on the ankles in an "open chain" exercise completed by straightening the leg. She said that both of these activities place tremendous pressure and torque on the patella and can be damaging.

Avoiding Injury
The American Academy of Orthopaedic Surgeons suggests several ways to minimize the risk of knee injury, including:

• Before starting a sports activity, do some sustained muscle stretching and three to five minutes of warmup with a jog or on a bike.
• Use the best equipment you can, especially good quality, sport-specific shoes.
• Don’t be a "weekend warrior" who plays hard only once or twice a week; include a half hour of regular exercise in a daily routine whenever possible.
• When you Increase your level of activity, do it in small increments using what’s called the 10% rule as a guide. For example, go from shooting baskets for 50 minutes to shooting baskets for 55 minutes or from running a mile to running 1.1 miles.
• Vary your routine with different exercises and activities that include both strength and aerobic elements.
• Keep your weight at a reasonable level – extra weight puts more stress on the knees.
• Don’t overdo it. When it feels like time to stop an activity, it probably is.

Dr Vetter advises baby boomers to continue the trend of fitness-based lifestyles. "We want you to be active," she said. "Stay active and keep up your strength because that maintains your health and the health of the knee joints. Becoming sedentary and gaining weight are the worst things you can do. From a medical perspective, we try and do whatever we can symptomatically to help you continue to be active."

"I have patients with bad arthritis who do excellent on a bike and will ride 100 miles, but they can’t jog," said Dr. Vetter. "So if you’re jogging and it hurts you may have to change the activity you participate in. You can still be active - and it’s important to participate in cardiovascular activities - but you might have to change the venue in which you’re doing it."

Dan Ullrich
HealthLink Contributing Writer

This article includes information from the National Institutes of Health (www.nih.gov) and the American Academy of Orthopaedic Surgeons (www.aofas.org).