What are Meniscus Tears?
The menisci are two crescent-shaped pieces of fibrocartilage located within the knee joint—one on the medial (inner) side and one on the lateral (outer) side. They sit between the femur (thigh bone) and the tibia (shin bone) and play a vital role in knee function.
Their primary functions include acting as shock absorbers, distributing load evenly across the joint, improving joint stability, and assisting with lubrication and nutrition of the cartilage. By increasing the contact surface between the femur and tibia, the menisci help reduce stress on the articular cartilage and protect the joint from wear and tear. Damage to the meniscus can compromise these functions, potentially leading to pain, mechanical symptoms, and an increased risk of developing knee osteoarthritis over time.
Causes
Meniscus tears can occur through both acute injury and gradual degeneration.
Acute tears are commonly seen in younger, active individuals and often occur during sports that involve twisting, pivoting, or sudden changes in direction. A typical mechanism is a forceful rotation of the knee while the foot is planted, which places stress on the meniscus and can cause it to tear.
Degenerative tears are more common in older adults and may occur with minimal or no specific trauma. Over time, the meniscal tissue becomes less resilient and more prone to fraying and tearing as part of the ageing process. These tears are often associated with underlying osteoarthritis.
Symptoms
Symptoms of a meniscus tear can vary depending on the size, location, and type of tear.
Common symptoms include:
- Pain : often localised to the inner or outer side of the joint. Worse when squatting, kneeling or twisting.
- Swelling : which may develop gradually over several hours or days.
- Mechanical : a catching, locking, or clicking sensation within the knee.
- Limited range of motion : difficulty bending or straightening the knee fully.
- Instability : and a feeling of giving way in some cases.
In certain types of tears, such as a “bucket-handle” tear, the knee may become locked in a partially bent position, requiring urgent medical attention.
Diagnosis
Diagnosis of a meniscus tear involves a combination of clinical evaluation and imaging. A detailed history is taken to understand the mechanism of injury, onset of symptoms, and any functional limitations.
During physical examination, your surgeon will assess for joint line tenderness, swelling, range of motion, and mechanical symptoms. Specialised tests, such as the McMurray test or Thessaly test, may be performed to help identify meniscal pathology. However, clinical examination alone may not always be sufficient, particularly in complex cases or when other knee injuries are suspected.
Imaging
Imaging plays an important role in confirming the diagnosis and guiding management. MRI is the most commonly used and most sensitive imaging modality for detecting meniscal tears. It provides detailed images of soft tissues, allowing visualisation of the menisci, ligaments, cartilage, and surrounding structures. X-rays may also be performed to assess for underlying arthritis or bony abnormalities, although they do not directly show meniscal tears.
MRI can also help identify associated injuries, such as ligament tears (including ACL injuries) or cartilage damage, which may influence treatment decisions.
Treatment
Conservative (non-operative)
Treatment of meniscus tears depends on several factors, including the patient’s age, activity level, type of tear, and presence of associated knee conditions. Many meniscus tears, particularly small or degenerative tears, can be managed non-surgically. Conservative treatment options include physiotherapy, which involves a structured rehabilitation program designed to strengthen the muscles around the knee, improve joint stability, and restore range of motion. Activity modification is also important, with patients advised to avoid movements that worsen symptoms, such as deep squatting or pivoting. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) may be used to help reduce pain and inflammation. As symptoms improve, a gradual return to activity is encouraged. With appropriate management, many patients experience significant improvement without the need for surgery.
Surgical Treatment
Surgical intervention may be considered when symptoms persist despite conservative treatment, or in cases of larger, unstable, or mechanically symptomatic tears. It is more commonly recommended for younger patients with traumatic, sports-related injuries. Arthroscopic (keyhole) surgery is the most common approach and allows the surgeon to directly visualise and treat the tear. Depending on the type and location of the tear, surgical options include meniscal repair, which involves suturing the torn edges together to allow healing and is typically performed when the tear is in an area with a good blood supply. Another option is partial meniscectomy, where the damaged portion of the meniscus is trimmed and removed while preserving as much healthy tissue as possible. Meniscal repair is generally preferred when feasible because it maintains the function of the meniscus and may reduce the risk of developing long-term arthritis; however, not all tears are suitable for repair.
Recovery
Recovery varies depending on the procedure performed. Meniscal repairs usually require a longer rehabilitation period with activity restrictions, whereas partial meniscectomy often allows a quicker return to normal activities.