The knee joint is formed by the union of two bones, namely the femur (thigh bone) and the tibia (lower leg bone). At the junction of these two bones is a cartilage called the meniscus, which acts as a shock absorber. There are two menisci – the lateral and medial menisci. The lateral meniscus is the outer meniscus of the knee joint and gives a cushioning effect during weight bearing activities. Lateral meniscus syndrome is characterized by an injury caused by the tearing of the cartilage tissue or a rare case of a congenital abnormality called a discoid meniscus, which results in knee pain.
Lateral meniscus syndrome often occurs due to excessive weight bearing and twisting motions to the knee. This occurs usually due to sports activities such as football, basketball and snow skiing, which require a lot of changes in directions and twisting movements. It can also occur due to the gradual wear and tear of tissues that occurs over time. As you grow older, degenerative changes may occur in the knee joint, causing injury with even small movements. The congenital abnormality, discoid meniscus, is more prone to injuries while performing twisting activities.
The common symptoms of lateral meniscus syndrome may include:
- Sharp pain associated with weight bearing activities, twisting movements, climbing stairs, kneeling or squatting
- Audible popping or clicking of the knee on the front or back
- Locking of the knee during certain movements
- Feeling of giving way of the knee
- Significant restriction of knee range-of-motion in severe cases
- Inability to straighten the knee completely
A thorough medical history and physical examination is done by your doctor to diagnose lateral meniscus syndrome. Other imaging techniques, such as X-ray and magnetic resonance imaging (MRI), are ordered to confirm the diagnosis. Sometimes, arthroscopy, a procedure where a fiber-optic tube with a light and camera is attached, is inserted into the knee to provide your doctor with a better view of the damage and confirm on the diagnosis of lateral meniscus syndrome.
Lateral meniscus syndrome is treated with physiotherapy and surgery.
- Physiotherapy: helps to optimize the healing process. This treatment includes soft tissue massage, use of crutches, electrotherapy (use of electrical energy for healing), hydrotherapy (use of water for treatment), ice or heat treatment, and progressive exercises to enhance strength, balance and flexibility of the knee joint. Physiotherapy is recommended before surgery.
- Surgery: Severe meniscal injuries would require surgery, especially when you experience locking of the knee. Surgery for this condition is performed with knee arthroscopy, a minimally invasive surgery that involves the removal or repair of the torn cartilage. The surgery is performed via small incisions through which an arthroscope and other surgical instruments are inserted.
If you have a minor lateral meniscus syndrome that is managed conservatively, you can return to sports activities in 2 to 4 weeks. If your condition is treated through surgery, it will take about 4 to 6 weeks for you to fully recover. Your leg will be placed in a soft bandage wrap or brace, and you may be prescribed crutches to help you walk. Surgically treated meniscus syndrome will require 6-8 weeks of physiotherapy.