Meniscus Injury
What is the Anatomy and Function of the Meniscus?
The meniscus refers to two C-shaped cartilage structures within each knee — the medial (inner) and lateral (outer) meniscus.
Each meniscus is made of fibrocartilage and sits between the femur (thigh bone) and tibia (shin bone), acting as a shock absorber and stabilizer for the knee joint.
The main functions of the menisci are to:
Distribute load and absorb impact during walking, running, and jumping.
Improve joint congruency by allowing smooth motion between the femur and tibia.
Protect the articular cartilage by spreading weight evenly throughout the knee.
Assist with joint stability and lubrication.
How Do Meniscal Injuries Occur?
Meniscus tears can occur from acute trauma or degenerative wear over time.
Acute tears are most common in younger, active individuals and usually occur when:
The knee twists or pivots.
The knee sustains direct impact.
Degenerative tears occur gradually with aging and repetitive micro-trauma, often in middle-aged or older adults, particularly when combined with early arthritis.
How Do You Diagnose a Meniscus Injury?
Diagnosis is based on a combination of history, clinical examination, and imaging.
Clinical Symptoms/History:
A history of twisting or squatting injury, or a gradual onset of pain without trauma.
Joint line pain/tenderness on the affected side.
Swelling and reduced range of motion.
Catching of the knee or loss of range of motion.
Imaging:
MRI is the gold standard for confirming a meniscus tear, identifying its size, pattern, and location, and assessing cartilage or ligament damage.
X-rays will be performed to rule out associated fractures or arthritis.
What are the Long-Term Consequences of Having a Meniscus Tear?
Meniscus tears lead to long-term consequences, which can include:
Persistent pain and swelling.
Recurrent locking or catching, affecting mobility and motion.
Progressive cartilage wear.
Early-onset osteoarthritis.
What are the Indications for Conservative Management of Meniscal Injuries?
Many meniscal tears can be managed successfully without surgery.
Conservative treatment is appropriate when:
The tear is degenerative in nature.
The patient has minimal pain and no mechanical locking or catching symptoms when moving the knee joint.
There is degenerative tearing associated with early arthritis.
Older and less active patients.
The knee is stable with intact ligaments.
Conservative management includes:
Rest and activity modification to reduce strain on the knee.
Physiotherapy to strengthen the surrounding muscles and improve joint mechanics.
Anti-inflammatory medication to reduce pain and swelling.
Injections (such as corticosteroids) in selected cases.
Most patients improve within 4–8 weeks of structured conservative management.
What are the Indications for Surgical Management of Meniscal Injuries?
Surgical treatment may be necessary when symptoms persist or when the tear is unlikely to heal on its own.
Indications for surgery include:
Persistent pain, swelling, or mechanical symptoms (locking, catching, clicking) despite conservative management.
Large or unstable tears, particularly those causing the meniscus to shift into the joint (bucket handle tears), causing loss of motion.
Tears in the stabilizers (“roots”) of the meniscus in the setting of minimal cartilage degeneration.
Tears in younger, active patients where the knee cartilage is healthy.
Associated ligament injuries (e.g., ACL tear) requiring surgical repair.
Failed non-operative treatment with ongoing functional limitation.
Surgical options include:
Arthroscopic meniscus repair – suturing the tear to preserve meniscal tissue (preferred when possible).
Partial meniscectomy – trimming the damaged section when repair is not feasible.
Meniscus transplantation – in selected young patients who have lost most of the meniscus and remain symptomatically painful.
