Jock Doc

After working out, sharp pain in your knee can mean torn cartilage

Q. Yesterday I twisted my left knee after spinning. I felt a catch and a sharp pain. I have trouble straightening my knee out or bending it all the way. It swelled a little bit. I went to urgent care and they took X-rays that showed nothing wrong. They gave me crutches and told me to see an orthopedic doctor if it still hurt after a few days. However, it is really uncomfortable and I wonder what I could have done to myself.

A. The most common cause of a “locked” knee after a twisting injury where a pop is felt is a torn meniscal cartilage. The meniscus is a shock absorber that sits between the ends of the the femur (thigh bone) and the tibia (shin bone). If it tears, the torn piece can get stuck between the bone ends causing pain and a catching or locking sensation.

Other possible causes of your symptoms include a torn ACL ligament, a loose body that gets stuck, or your kneecap coming out of alignment. I recommend you see an orthopedic surgeon as soon as possible. He or she will likely examine you and probably get an MRI scan. X-rays only show the bones; the MRI scans show soft tissue structures, such as cartilage and ligaments. If you have a torn meniscus as I suspect, this usually require arthroscopic surgery to repair the problem.

Dr. Harlan Selesnick is team physician of the Miami Heat and director of Miami Sports Medicine Fellowship, Doctors Hospital. Send your questions to