Posterolateral corner injuries

Posterolateral Corner Injuries of the knee are complex injuries that involve damage to the posterolateral corner (PLC) structures, which are crucial for stabilizing the knee against varus force, external rotation, and posterior translation. The PLC is composed of various ligaments, tendons, and muscles, including the lateral collateral ligament (LCL), the popliteus tendon, the popliteofibular ligament, and the biceps femoris tendon. These injuries often occur in conjunction with other knee injuries, such as anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) tears.

Etiology

Posterolateral corner injuries are typically the result of a traumatic event, such as a sports injury, motor vehicle accident, or a fall. The mechanism of injury usually involves a direct blow to the anteromedial knee, hyperextension, or a severe varus force. Athletes participating in contact sports like football, soccer, and skiing are at a higher risk of sustaining these injuries.

Clinical Presentation

Patients with PLC injuries often present with pain and swelling in the posterolateral aspect of the knee, instability, and difficulty walking. A feeling of the knee giving way, especially when navigating turns or twisting movements, is common. Physical examination may reveal varus instability, increased external rotation, and a positive posterolateral drawer test.

Diagnosis

Diagnosis of posterolateral corner injuries involves a thorough clinical examination and imaging studies. Magnetic resonance imaging (MRI) is the gold standard for visualizing the extent of the injury and assessing any associated injuries to the cruciate ligaments or menisci. Stress radiographs can also be useful in evaluating the degree of lateral and rotational instability.

Treatment

The treatment of PLC injuries depends on the severity of the injury and the presence of concomitant knee injuries. Non-operative treatment, including physical therapy and bracing, may be considered for isolated, mild injuries. However, surgical intervention is often required for moderate to severe injuries or when other ligamentous injuries are present. Surgical techniques aim to repair or reconstruct the damaged structures to restore stability to the knee.

Rehabilitation

Rehabilitation following PLC injury is crucial for a successful recovery, whether the treatment is operative or non-operative. The rehabilitation program typically includes exercises to restore range of motion, strengthen the muscles around the knee, and gradually return to functional activities. The duration of rehabilitation varies depending on the severity of the injury and the type of treatment received.

Prognosis

The prognosis for patients with posterolateral corner injuries varies. With appropriate treatment and rehabilitation, many patients can return to their previous level of activity. However, the presence of concomitant knee injuries and the severity of the PLC injury can affect the overall outcome. Early diagnosis and treatment are important to minimize the risk of long-term instability and degenerative changes in the knee.