The lateral meniscus is the crescentic wedge-shaped structure seated on the top of the tibia (shinbone) on the lateral (outer) side of the knee joint.

Page updated October 2023 by Dr Sheila Strover (Clinical Editor)

the lateral meniscus



The lateral meniscus is more mobile than the medial meniscus, and it is less prone to tears. However, its anatomy makes it particularly vulnerable if it is damaged.


What is the difference between lateral meniscus and medial meniscus?

The lateral meniscus differs considerably from the medial meniscus. It is O-shaped, rather than C-shaped, and is much more mobile than the medial meniscus and there is much less attachment around the outer rim to the capsular walls. In addition, the tendon of the popliteus muscle passes between the outer rim at the back of the meniscus and the capsule

Popliteus muscle and tendon in relation to the lateral meniscus

This illustration is from the back of the knee, looking at how the tendon of the popliteus muscle on the lateral side pierces the capsule and passes alongside the lateral meniscus on its way to insert on the femur. There is no equivalent on the medial side.

This complex area is called the 'posterolateral corner'. Injuries here may be a challenge to the surgeon.

Back to top


What does the lateral meniscus do?

Both lateral and medial menisci act as shock absorbers and stabilisers of the knee joint. Both are packed with fibres which are arranged in a structured network which makes the structures strong and help them avoid stress tears. The wedge-shape, and the presence of ligamentous attachments to the underlying tibia bone, help to stabilise the joint.

Back to top


Can you walk with a lateral meniscus tear?

One can still walk with a lateral meniscus tear, although tears involving the posterolateral corner may be associated with feelings of instability.

Back to top


Can a lateral meniscus tear heal by itself?

Small tears may heal, but tears of the posterolateral corner are much less likely to heal on their own. The person may develop some bowing of the knee compared to the other side, and experience uncomfortable instability.

Back to top


How serious is a lateral meniscus tear?

A lateral meniscus tear is potentially a lot more serious than a medial meniscus tear because of its particular vulnerabilities. The high mobility, the weaker outer rim and the poorer attachment to the capsule render it prone to instability once it is injured.

Back to top


Forum discussions

Back to top


Peer-reviewed papers

Back to top


lateral knee cartilage
outer knee cartilage

Injury of the small muscle at the back of the knee may be confused with a torn meniscus.


Dr Sheila Strover (Editor)
BSc (Hons), MB BCh, MBA

See biography...

Other relevant material -

Short course -

Dr Frank R Noyes2013 - Posterolateral corner injuries of the knee - by Dr Frank R Noyes (Knee Surgeon)


Peer-reviewed papers -

eBook about cartilage terminology

eBook download - Clearing up confusion about knee cartilage

by Dr Sheila Strover (Clinical Editor)