Editor's Note: This article was originally written by Daniel O'neill, M.D.
Human beings are well designed for many things. We have large brains for poetry and quantum mechanics; we are good long distance runners, and of course have these awesome opposable thumbs. Unfortunately, some parts are not designed very well for our 21st century lifestyles. The low back, or lumbar spine, is first on my list for sending back (or forward?) to the engineers. A close second though might be the "knee cap" or patellofemoral joint.
The "knee cap" or patella is an ovoid shaped bone whose main purpose is to act as a fulcrum that big muscle on the front of your thigh, the quadriceps. (I'll wait while you grab your high school physics book). There are plenty of folks who do not have patellae, but because this causes the quad muscle to work inefficiently, few of these folks can run or climb stairs well. The design issue with the patella is that it articulates, or rubs up against, the end of the femur bone (thus the "patellofemoral" joint). For those of us who have patellae, by the time we are 65 years old, the vast majority will show arthritis in the patellofemoral joint. And a full 50% of people in this age-group will complain of pain in their knees. FIFTY PERCENT Any time you have half of all people complaining about something, you need to redesign. (We'll talk about Congress some other week!)
So, since we cannot fast forward a few hundred thousand years, what can we do to prevent some of this arthritis? First, one risk for knee arthritis is the way your knees, hips, and ankles are aligned. There are some big operations for those horribly aligned and these will often be done in teenagers once they have finished their growth spurt. For most people with only small alignment issues, preventing knee problems should start with good shoes and good posture. We will have the debate about whether wearing any shoes is good for your feet in another column. Since the last time I checked most of you are walking on asphalt, cement, tile, and other hard surfaces, let's assume for now shoes are useful.
In addition to good shoes and posture, whenever we talk about any kind of health - from your brain to your heart to your knees to your feet, you need to stay fit and eat well. As much as I regret it, there is not a disease or aging process in the human body that responds favorably to more pepperoni pizza.
Next up for patellofemoral health: strong core muscles. Having strong muscles in the back, chest, abdomen and hips actually helps protect your knee. Thus, stretching and strengthening the core, whether with Pilates, yoga, or a well-designed exercise program, needs to be part of every fitness routine.
Time to focus on your knees. Here's my rule: strengthen your hamstrings, stretch your quads. Now, this does not mean you can have tight hamstrings and weak quads, but most people exercise these muscles in the course of their work outs and sports. Hiking, cycling, and stair climbing, all work your quads, and can be tough on your patellae. When people do stretch, they will often touch their toes or push up against a pole, thus stretching the hamstrings. The front of your body - the front of your shoulders, hips, and knees - spend a lot of time folded forward, and thus need to be specifically stretched.
Similarly, hamstrings need to be strengthened with specific exercises. Hamstring curls on an exercise ball (sometimes called a physioball or stability ball) are one of my favorites. You can find examples of these in my book or on my website.
While still in the gym, stop using the "knee extension" machine from ninety degrees (your knee at a right angle) to zero degrees (the knee straight). This puts tremendous stress across the patella. Extend only from 45
° to zero one leg at a time when using this machine. Also, when doing squats or the sled, bend your knees only to about 45 degrees. In other words, don't squat low with the weights like you see in the Olympics. 45 degrees will give you plenty of strengthening without doing undo damage to your knees.
Finally, don't do jobs that require a lot of kneeling, squatting, kicking carpets, running down mountains, etc. Invest in a garden stool, knee pads, "traverse" while walking or running down a steep hill or, if you cannot avoid knee abusing activities at work, consider law school! After an active day, give yourself a good stretch and put some ice on those knees. Remember, it's not just about what you do, it's how you recover.
Shoot me an email to discuss the patella or any other orthopaedic issues. Now turn off the computer and get outside!
Dr. Daniel O'Neill, M.D., Ed.D, F.A.A.O.S. is an Orthopaedic Surgeon, Sports Psychologist, and founding member of The Alpine Clinic based in Franconia New Hampshire.