Meniscus

Meniscal lesions are very common, whether in athletes or with age. Here is a detailed explanation of the nature of these injuries and their mechanisms.

What is a meniscus?

In each knee, there are two menisci (one medial and one lateral). These are small, crescent-shaped fibrocartilage pads located between the femur and the tibia. Their roles are essential:

• Shock absorbers: They absorb shocks and distribute body weight.
• Stabilizers: They improve the fit of the bones.
• Lubricators: They facilitate the gliding of the joint.

[Image of an axial view of the knee menisci]

The two types of lesions

There are mainly two origins for meniscal tears:

1. Traumatic lesion (The "shock")

It often occurs in young athletes. It is caused by a sudden movement, such as a pivot (the foot remains fixed while the body turns) or a sudden straightening from a prolonged squatting position.

• Bucket-handle tear: This is a significant longitudinal tear. Part of the meniscus can fold into the joint, causing knee locking (inability to extend the leg).

2. Degenerative lesion (Wear and tear)

It occurs with age (often after 40-50 years). The meniscus loses its flexibility and gradually frays. It can appear without any particular trauma, simply due to the accumulation of stress from daily life.

[Image of a bucket-handle meniscal tear]

Symptoms and Diagnosis

The signs that should raise concern are:

• Localized pain on the side of the knee (along the joint line).
• Swelling of the joint.
• Episodes of locking or a sensation of internal catching.
• Pain when squatting.

The diagnosis is suspected during a clinical examination (specific pressure maneuvers on the meniscus) and confirmed by an MRI, which allows precise visualization of the shape and extent of the tear.

Treatment: Should surgery be performed?

Contrary to popular belief, surgery is no longer systematic.

• Rest and Physiotherapy: For degenerative or minor lesions, medical treatment is often favored to calm inflammation and strengthen muscles.
• Surgery (Arthroscopy): If pain persists or in case of locking, the surgeon may intervene. We try as much as possible to repair (suture) the meniscus. If this is not possible, only the damaged part is removed (partial meniscectomy), taking care to leave as much as possible to protect the cartilage in the long term.

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