The meniscus is a soft cartilage cushion between the two knee bones that acts as a cushion and helps to distribute loads over a larger area. There are two menisci in the knee. The medial meniscus is on the inner side of the knee, and the lateral meniscus is on the outer side. A meniscus tear may occur due to injury or wear and tear. A torn meniscus causes knee pain and may cause symptoms such as catching or locking. A meniscus tear can be diagnosed using a test called magnetic resonance imaging (MRI). A patient with a torn meniscus on the MRI who remains symptomatic often requires meniscus surgery. Surgery to treat a medial meniscus tear or a lateral meniscus tear is performed using an instrument called an arthroscope. Small incisions are made in the skin to insert a tube connected to a television camera and instruments. Meniscus surgery involves removing the torn meniscus and saving as much of the good meniscus tissue as possible. In some cases it is possible to sew the broken meniscus back together, a process known as meniscus repair.
