Collateral ligament tear in the knee

When the knee is exposed to excessive lateral force, the collateral ligaments can tear. Collateral ligament tears usually occur during sporting activities such as football and skiing. Medial collateral ligament tears are much more common than lateral collateral ligament tears. These types of injuries can usually be treated conservatively, in other words, without surgery.

The knee joint is stabilised by the surrounding muscles, the kneecap, the meniscuses and the knee ligaments. The knee has four ligaments: two cruciate ligaments, a medial collateral ligament and a lateral collateral ligament. Cruciate ligament tears are explained in the cruciate ligament tear section. Collateral ligament tears usually occur when excessive force is applied to the knee as it is twisting. Such situations typically arise while playing football or skiing. The medial collateral ligament on the inner side of the knee joint tears much more frequently than the lateral collateral ligament.

Often it is possible to hear the ligament tearing. The side of the knee with the tear becomes very painful and often develops a bruise. The knee’s mobility is restricted and the joint becomes unstable.

The diagnosis is based on the type of injury and a thorough examination of the knee. If there are signs that a bone or the meniscus may be damaged, computed tomography or an MRI examination will also be carried out.

In the case of a simple ligament tear without any bone or meniscus damage, the collateral ligament can be treated conservatively. Conservative treatment consists of resting the knee and cooling the knee joint, which is usually swollen. This is combined with pain killers and anti-inflammatory medication. As soon as the pain has subsided, the patient begins a targeted programme of physiotherapy exercises designed to stabilise the joint. Strengthening the surrounding muscles is an important aspect of the treatment and it also helps to prevent future ligament tears in the knee.

If the ligament injury involves a damaged meniscus or fractured bone, then an operation is recommended – usually arthroscopic surgery of the knee. Find out more about this in the knee joint imaging section.