Knee Meniscus Injuries

knee_anatomy

 

The knee meniscus is a pair of fibrocartilaginous structures found in between your thigh bone (femur) and leg bone (tibia). The one on the inner side of the knee is known as the medial meniscus, and the one on the outer side is known as the lateral meniscus. The pair of C-shaped menisci are important shock absorbers in the knee joint and prevent bone to bone contact. They also deepen the knee joint and together with the ligaments, they keep the joint stable.

Meniscal injuries can happen with or without trauma. In younger people, traumatic meniscal injuries are more common and occur frequently during activities where the individual twists the knee while it is slightly bent.  Atraumatic meniscal injuries are usually degenerative and occur in the older population. In degenerative meniscus injuries, the cartilage weakens and becomes worn out and thinner, making it more prone to injury. A degenerate tear may develop gradually or may occur suddenly with simple activities like landing from a step or standing up from sitting.

With a meniscus injury, pain is localised in the knee joint. There may be associated swelling, clicking or the person may describe locking and/or instability of the knee joint during activity. Pain is aggravated by knee movements and loading (such as walking, running, squatting, and climbing stairs). A meniscus injury can be diagnosed with clinical tests but your physiotherapist or doctor may send you for an MRI to confirm and rule out other injury to surrounding structures in the knee joint.

Management of a torn meniscus depends on several factors, such as type of tear, location and size of tear, extent of locking and instability. The outer ring (called the ‘red zone’) of the meniscus has good blood supply, so small tears tend to heal better by itself. Larger tears or tears in the inner portion of the meniscus (called the ‘white zone’) which has poorer blood supply is less likely to heal by itself, therefore requiring surgery.

For conservative management of meniscal tears, it is important to see a Physiotherapist. In the acute phase, your physiotherapist will use various treatment techniques such as effleurage, electrical therapy, ice therapy and taping to reduce swelling, inflammation and pain. You may also require some anti-inflammatories in this initial stage. If your knee is stiff, they will use manual therapy or teach you appropriate flexibility exercises to restore normal range of movement.

In order to reduce further stress on the injured meniscus, it is important to strengthen your knee so that your knee becomes more stable. In the acute episode, it is possible and beneficial to start simple strength exercises. Your physiotherapist will guide you on a graded and progressive rehabilitation program from initial injury to return to sport or activity. A comprehensive program will involve strengthening, proprioception, agility and sport-specific training to help you get back to sports without pain and safely so that you minimise chances of another injury.