Your Questions About Knee Pain

Medically Reviewed by Tyler Wheeler, MD on May 06, 2023
2 min read

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 pain.

What kind of injuries can cause knee pain?

They’re usually twisting injuries to the knee: ACL, meniscus, or ligament injuries.

What's the difference?

The main difference between arthritis and other kinds of knee pain is there's no trauma associated with it. A person who tore their ACL or had a meniscus injury knows exactly when it happened. With arthritis, it's more of a dull, aching pain. It gets worse as time goes on.

Will my pain go away on its own?

It depends. Arthritis pain tends to wax and wane over time. It may not completely go away, but sometimes it feels much better. Pain from an injury improves at first, but if you're left with a sore joint, you may not be able to do certain activities.

When do I need to see a doctor?

Everyone has a different pain threshold. If you’ve an injury and your knee swells, you need to see your doctor. Even if the swelling goes away, you need to have your knee examined -- you might have injured something inside the joint. If you have arthritis pain and the bad days outnumber the good, you should see your doctor.

How do I keep my knees healthy?

I think weight control is important. Flexibility helps as well. If you take part in a sport that requires a lot of physical exertion, like skiing or tennis or soccer, you need to get in shape.

Also, when you get tired, you need to stop. Look at the rate of knee injury: It goes up in the fourth quarter or final period of a game. Just a millisecond or two of delay of muscle function can cause injury. If the muscles that protect the ligament are tired, they don't do a good job.