Although tears in the meniscus --- a small piece of cartilage in your knee --- occur more often in contact sports such as football, runners also can suffer meniscus tears. If you've torn your meniscus while running or playing a sport, you may need surgery. Even if you only have a minor meniscus injury, you'll need to rest your affected knee for several weeks or more, meaning you won't be able to run on it. Always follow your doctor's orders after suffering an injury.
Meniscal Injury
Your knee depends on your meniscus cartilage to form "shock absorbers" between the bones in that joint. Consequently, you place your meniscus under great stress whenever you turn or squat rapidly and when you're running for long periods of time. If you're older, you're more likely to have a weakened meniscus that can tear during running, according to the American Academy of Orthopaedic Surgeons. Tears can range in severity from relatively minor, in which only a small flap tears away from the main cartilage, to major, in which the tear splits the meniscus in half.
Symptoms
If you tear your meniscus while running, you may feel a popping sensation, likely followed by pain in the joint, according to the Hospital for Special Surgery. You might be able to walk or even run on the knee, but it probably will feel unstable, as if it might not support you. Your knee may swell up and become stiff, and you may not be able to move it through its full range of motion. Don't run on your knee in this condition; instead, visit your physician to determine the severity of your meniscus tear.
Treatment
Your doctor may use X-rays or magnetic resonance imaging --- an MRI for short --- along with a physical exam to confirm that you've torn your meniscus and to recommend treatment options. She also may decide to look inside your knee with a tiny surgical instrument called an arthroscope to see what exactly has torn, the Hospital for Special Surgery explains. If you've torn your meniscus in an area where there's a rich blood supply, it may be able to heal itself. If the tear is very minor, you may only need to rest the knee, apply ice and compression and elevate the joint. Otherwise, your doctor may recommend arthroscopic surgery to snip away the pieces of torn cartilage.
Resuming Running
Regardless of whether or not you have surgery to repair your torn meniscus, you'll wind up sidelined from running for at least several weeks. If your doctor tells you that you only have a minor tear and to rest the joint but you continue to run on it, you'll risk permanent damage, so don't run until you've got the green light from your physician. If you do have surgery to repair the torn meniscus, you'll likely need physical therapy to regain full function in your injured knee. Your knee should regain full function within about four to five months following the surgery, according to the University of Washington's Orthopaedics and Sports Medicine Department, and you shouldn't begin running again without your doctor's OK.


