Understanding knee pain

Knee pain is a common condition that's often misunderstood. Here's what you need to know when knee pain stops you in your tracks.

• Cause: Knee pain has so many ways to find you: an injury that tears cartilage or ruptures ligaments; infections or conditions such as arthritis and lupus; unstable kneecaps; in rare cases, even tumours can invade the knee.
• Statistics: Whatever its cause, knee pain is common: Almost one in three people over age 45 experience it.
• Physiology: The knee, after all, is a complicated joint that sees a lot of action. It includes the main knee joint, where the thighbone and shinbone meet, and a secondary joint, where the kneecap is attached to the thighbone. These joints bend and straighten, twist and rotate. Wrapped around the knee, giving it stability and strength, is a series of ligaments. Between the joints is a thick cartilage called the meniscus that absorbs the pounding of every step you take.

• Signs: Aside from pain, the signs that something's amiss vary, depending on which part of your knee is affected.
• Ligament: If something's wrong with a ligament, you may hear popping sounds when you move, be unable to put your weight on your leg, or feel that your knee is about to buckle.
• Tendon or kneecap: If the tendon or kneecap is affected, you may have swelling, be unable to straighten your knee, or feel like your knee is about to give way.
• Meniscus: If the meniscus is torn, you may have slow swelling and your knee may feel frozen in place.
• Bursitis: It may show up with swelling, redness, and fever. Fortunately, in most cases, you have many ways both to manage the pain and to get your knee back up to speed.

• Medical evaluation: Your doctor is going to ask you a lot of questions, such as when your knee started hurting, if the pain started suddenly or slowly, if you've had knee pain before, and if the pain is in one spot or several. He will want to know if you can stand on or bend your knee, if the pain comes and goes, if you've been doing anything that stressed your knee, like playing basketball or beginning a new exercise program. He'll want to know what makes the pain better or worse, and he'll check for bruising and swelling. He'll ask you to move your leg in different ways.
• Testing: He may also do imaging tests such as X-rays or an MRI, checking for damage, and he may perform blood tests or draw fluid from the injured joint to check for infection or other sources of inflammation.

• Research: A Tufts University study of more than 700 people found that just 20 to 30 minutes of daily leg exercises using elastic bands significantly reduced knee pain and stiffness.
• Ask your doctor which treatments are right for you.