Being active is one of the best things you can do for your joints and the rest of your body. But injuries can happen, and your knees are particularly vulnerable. Some of the most common problems are sprained ligaments, meniscus tears, tendinitis, and runner's knee. If you have an old knee injury that wasn’t properly treated, it may flare up now and then or cause constant pain.
Your knee hurts and you want to know why. Whether it's an injury or arthritis, here are answers from Joseph Bosco, MD. He's an orthopedic surgeon who specializes in sports medicine and knee care at the NYU Langone Medical Center's Hospital for Joint Diseases.
Could my pain be from osteoarthritis?
Yes. Probably 95% of knee pain caused by arthritis is osteoarthritis, which is caused by “wear and tear” on the joints. Other types, like rheumatoid arthritis, are much less common causes of knee...
Bursitis: A bursa is a sac containing a small amount fluid that’s under the skin above your joint. Overuse, falls, or repeated bending and kneeling can irritate the bursa on top of your kneecap, causing pain and swelling. Doctors call this prepatellar bursitis. It’s also called ''preacher's knee."
Dislocated kneecap: The kneecap slides out of position, causing knee pain and swelling. Your doctor may call this “patellar dislocation.”
IT (iliotibial) band syndrome: The iliotibial (IT) band is a piece of tough tissue that runs from your hip down to the outer part of your knee. When you overdo activity, it can become inflamed over time. That causes pain on the outer side of the knee and is common in runners when going downhill.
Loose cartilage: Sometimes, a knee injury can break loose cartilage. These pieces can get stuck in the joint, which causes pain and swelling. Many times people will have the sensation of “catching” in the joint when they are active.
Osgood-Schlatter disease: This condition happens when you’re young, when bones and other parts of the knee are still changing. It can cause a painful bump below the knee, where a tendon from the kneecap connects to the shin. Overdoing exercise, and irritation at a point on the bottom of your knee, called the tibial tubercle, often make this area hurt. The ache may come and go over time. It's especially common in teenage boys and girls.
Osteoarthritis: This is the “wear and tear” type of arthritis. It’s a top cause of knee pain after age 50. This condition causes the knee joint to ache or swell when you’re active. Joints affected by osteoarthritis can also be stiff early in the day.