Cartilage within the knee joint
There are two main types of cartilage within the knee joint. The shock-absorbing cartilages or menisci are colloquially known as the knee cartilages. These very specialised gristle pads conform to the shape of the knuckles of the knee joint in the tibiofemoral compartments. They distribute pressure, enhance stability and help the knuckles rotate and slide or glide across each other. They are commonly damaged, particularly in middle age, and this damage is often referred to as torn cartilage or meniscal tear.
Chondral cartilage covers the running surfaces of the knee joint and is also a very specialised material, providing lubrication, some shock-absorption, and distributing pressure evenly over the knuckles of the joint. It varies in thickness from between a few millimetres to almost a centimetre in depth, and unfortunately is easily damaged. It has limited healing potential and cumulative damage associated with loss of cartilage volume eventually leads to the development of osteoarthritis in old age.