What is a Meniscus Tear?

There are two menisci in your knee; each rests between the thigh bone (femur) and shin bone (tibia). The menisci are made of tough cartilage and conform to the surfaces of the bones upon which they rest. One meniscus is on the inside of your knee (medial), and the other meniscus rests on the outside of your knee (lateral). These menisci function to distribute your body weight across the knee joint and allow the bones to smoothly glide against each other without causing damage to the opposing bone.

The two most common causes of a meniscus tear are due to traumatic injury (often seen in athletes) and degenerative processes (seen in older patients who have more brittle cartilage). The most common mechanism of a traumatic meniscus tear occurs when the knee joint is bent and the knee is then twisted. Individuals who experience a meniscus tear usually experience pain and swelling as their primary symptoms. Another common complaint is joint locking, or the inability to completely straighten the joint. This is due to a piece of the torn cartilage physically impinging the joint mechanism of the knee.

The most common symptoms of a meniscus tear are knee pain, swelling of the knee, tenderness when pressing on the meniscus, popping or clicking within the knee, and/or limited motion of the knee joint.