The knee has two menisci, which are C-shaped soft cartilages, functioning as shock absorbers.
Both the medial (inner) and lateral (outer) compartments of the knee have a soft cartilage shock absorber. This meniscus cartilage is anchored to the bone only at its anterior and posterior extreme points. This allows the rest of the cartilage to expand outwards with load thus performing a shock absorber function within the knee.
The meniscus also improves the congruency of the two articulating surfaces of joint.
Loss of part or all of a meniscus decreases that particular cartilage’s ability to perform its function as a shock absorber. The end result is more rapid degeneration of the articular cartilage which lines the bony surfaces within the knee.
Loss of lateral meniscus tends to produce much faster deterioration than loss of the medial meniscus.
As the meniscus function is so important in preserving the longevity of the knee, preservation of as much as possible of the meniscal cartilage is crucial whenever managing a tear of this cartilage.
Traditionally, the meniscus has been divided into three different zones with blood supply decreasing from the inside to outside edge. Thus healing potential diminishes as one gets closer to the inner edge.
This model is incorrect. Multiple recent scientific studies have demonstrated that in fact all areas of the meniscus have the potential to heal.
This evidence makes it even more important that every endeavour is made to preserve as much as possible of the meniscal cartilage when a tear is diagnosed.
Acute or fresh tears have the potential to heal spontaneously (without surgery), if diagnosed and managed early with protective bracing, physiotherapy and the cessation of all impact sports.