The medial meniscus is on the inside of the knee, it is attached to the ligaments on the inside of the knee (MCL) and the joint capsule.  As it is more firmly attached to the deep structures of the knee, it is more commonly injured than the lateral meniscus. It takes approximately 50% of the weight across the medial (inside) compartment of the knee. The lateral meniscus is on the outside of the knee, it is more mobile and ‘C’ shaped than the medial meniscus.  It takes up to 80% of the weight across the outside compartment fo the knee.

The medial meniscus is on the inside of the knee, it is attached to the ligaments on the inside of the knee (MCL) and the joint capsule.  As it is more firmly attached to the deep structures of the knee, it is more commonly injured than the lateral meniscus. It takes approximately 50% of the weight across the medial (inside) compartment of the knee. The lateral meniscus is on the outside of the knee, it is more mobile and ‘C’ shaped than the medial meniscus.  It takes up to 80% of the weight across the outside compartment fo the knee.

In cross section the meniscus looks like a triangle – with the apex (tip) on the inside and the base on the outside.  The two parts of the meniscus form a ‘bow tie’ on an MRI scan.

There can be variations of the natural anatomy which can cause the meniscus to tear –  a “Discoid” Meniscus.  This is where the meniscus develops into a semicircular shape, rather than a crescent shape.  It lacks the stability of a normal meniscus, and consequently can tear more easily.