Rupture Of Lateral Ligaments

The lateral ligaments of the knee are two, the medial collateral ligament and the lateral collateral ligament. These ligaments are located on either side of the knee. Together with the anterior and posterior cruciate ligaments, they form the four main ligaments of the knee. They mainly provide stability to the knee in the lateral plane. The medial collateral stabilises the medial side of the knee while the lateral collateral stabilises the lateral side.

The injury occurs when an external force is applied laterally to the knee joint from either the inside or the outside. Injuries or tears of the lateral ligaments coexist quite often with tears of the cruciate ligaments or tears of the menisci. Injuries to the lateral cruciateligaments can range from simple strain to complete rupture and are categorized into 3 grades:

• Grade 1: when the ligament is slightly stretched but maintains stability at the knee.

• Grade 2: when the ligament is stretched and the fibres are partially ruptured.

• Grade 3: when the ligament is completely ruptured and no longer provides stability to the knee.

When the collateral ligaments undergo any degree of rupture they exhibit symptoms that include:

• Pain on the inner or outer side of the knee depending on which side is injured, local tenderness when palpating the affected area.

• Swelling at the site of the injury.

• Sensation of instability in the knee.

• Difficulty in walking.

• Loss of full range of motion.

After the clinical examination, imaging tests (X-rays and MRI) are usually required to determine the degree of stretching and/or rupture of the collateral ligaments, while in addition, a musculoskeletal ultrasound may be performed for a more detailed investigation of the damage, in order for the orthopaedic doctor to decide on the appropriate treatment.

Depending on the degree of rupture and the extent of the damage, the following is done:

Conservative Treatment

• The RICE rule, i.e. Rest, Ice, Compress and Elevate to reduce swelling.

• Ice therapy.

• Use of a special femoral knee brace.

• Anti-inflammatory medication.

• Physiotherapy (full programme of strengthening exercises).

Healing depends on the degree of damage and usually takes 3 to 6 weeks. It is necessary to properly repair the tear of the medial and lateral collateral ligament by carefully following the steps of the treatment, as well as the initial treatment of any other ligamentous lesions. Incorrect rehabilitation can lead to chronic knee instability.

Surgical Treatment

In case the rupture is not treated with conservative treatment or incorrect rehabilitation and in cases of chronic instability of one of the collateral ligaments, surgical repair is the solution to the problem. The aim of surgical rehabilitation is to stabilise the knee with the ultimate goal of avoiding secondary damage that may occur due to instability such as meniscal tears, articular cartilage injury and osteoarthritis.