In sports, a meniscus tear usually happens suddenly. Severe pain and swelling may occur up to 24 hours afterward. Walking can become difficult. Additional pain may be felt when flexing or twisting the knee. A loose piece of cartilage can get stuck in the joint, causing the knee to temporarily lock, preventing full extension of the leg.
If you have a torn meniscus, you may:
- Be unable to extend your leg comfortably and may feel better when your knee is bent (flexed).
- Develop pain gradually along the meniscus and joint line when you put stress on your knees (usually during a repeated activity). This most often happens when the tear develops over a period of time.
- Have swelling, stiffness or tightness in your knee.
Causes and Risk Factors
A meniscus tear can occur when the knee is suddenly twisted while the foot is planted on the ground. A tear can also develop slowly as the meniscus loses resiliency. In this case, a portion may break off, leaving frayed edges.