Meniscus Tears: Symptoms, Diagnosis and Surgical Repair

What Is the Meniscus?

The knee contains two C-shaped pieces of fibrocartilage called the medial meniscus (inner) and lateral meniscus (outer). They act as shock absorbers, distribute load across the knee, and stabilise the joint. The meniscus also protects the underlying articular cartilage from excessive compressive forces.

How Do Meniscus Tears Occur?

Meniscus tears can be acute, typically from a twisting injury during sport, or degenerative, occurring gradually with age and wear. Acute tears are common in young athletes. Degenerative tears are more common in middle-aged and older adults and are often associated with early knee arthritis.

Symptoms

• Pain along the joint line (medial or lateral), often pinpoint
• Swelling within 24–48 hours of injury
• Stiffness and reduced range of movement
• A clicking, catching or locking sensation
• A "locked knee" — inability to fully straighten the knee — indicates a bucket-handle tear requiring urgent attention

Diagnosis

Clinical examination includes joint-line tenderness and McMurray test. MRI is the investigation of choice, with high sensitivity and specificity for meniscal tears.

Treatment Options

Many meniscus tears can be managed non-operatively, particularly degenerative tears in older patients, with physiotherapy, NSAIDs, and activity modification.

Surgery is indicated for:

• Locking or mechanical symptoms not responding to conservative treatment
• Acute tears in young patients with repairable tissue
• Tears associated with other ligament injuries

Meniscus Repair vs. Removal

Meniscus repair is preferred wherever possible, the torn edges are sutured back together. Repair is most successful in the outer third of the meniscus (well-vascularised "red zone") and in younger patients. Recovery from repair is longer (3–4 months) but preserves meniscal function.

Partial meniscectomy (removal of the torn fragment) provides faster recovery (4–6 weeks) but removes meniscal tissue that cannot be replaced. Preserving as much meniscus as possible reduces the risk of future knee arthritis.

Further Reading

Dr Mooney has written in more detail about this topic on his own site: meniscal repair and knee arthroscopy for meniscal tears.