Doc MacLean

Torn knee cartilage need not spell end of sporting activity

A TORN knee cartilage, or meniscus, is a common injury in sport. The two menisci are made of tough fibrocartilage and lie within each knee joint on the surface of the Tibia or shin bone.

They are semi-circular in shape and principally act as shock absorbers during weight-bearing activity.

Injury usually occurs as a result of twisting at the knee when the joint is weight bearing. As a result the cartilage gets jammed between the Tibia and Femur or thigh bone. If the force is sufficient, a tear of the meniscus will occur.

Unfortunately damage to other structures, particularly the collateral knee ligaments, often occurs at the time of injury. The main symptoms are pain and swelling especially on running or weight bearing – some times the torn piece of cartilage gets trapped causing the knee to click on movement or even to “lock” in one position.

If the tear is small, the pain and swelling may settle but, in professional sportspeople, surgery is usually required before normal activity can be resumed.

In the past this surgery involved opening the joint and removing the whole cartilage, not just the torn portion. This was a much more invasive procedure with a significantly prolonged rehabilitation. Loss of the whole of the cartilage and its shock-absorbing function inevitably resulted in premature arthritis of the joint and potentially knee joint replacement at a younger age than usual.

Nowadays the operation is carried out by key hole surgery using an arthroscope which involves a small camera being inserted into the knee joint allowing the surgeon to trim the tear while preserving as much of the cartilage as possible to limit the risk of later arthritis of the joint.

The usual rehabilitation programme lasts between 4-6 weeks. This will vary due to the size, extent and location of the tear and is significantly longer if the cartilage is repaired rather than the tear trimmed.

Initial weight-bearing is limited, so pool work is ideal. This helps to restore the range of knee movement and maintains cardiovascular fitness without any weightbearing. Quadriceps and hamstring exercises as well as range of movement and balance should be initiated as soon as possible. As the rehab progresses, cycling activity is added followed by further weightbearing activity before gentle jogging which should be limited initially and progressive.

Finally sport specific activity is added such as twisting and turning in football before work with the ball is begun.