Knee Ligament Injuries

Overview

The knee is made up of two sets of strong ligaments that help to stabilize the joint. The collateral ligaments include the medial (or inside) and lateral (or outside) collateral ligaments, which connect the thigh bone (femur) to the shin bone (tibia) and stabilize the knee. The cruciate ligaments (anterior or “front”, and posterior or ‘back”) cross in the inside of the knee and prevent excessive front-to-back and twisting motions. Additional stabilizing structures also play a role in normal knee function.

Knee ligaments are usually injured by a sudden traumatic event such as a blow to the knee, twisting, falls, or motor vehicle accidents. The severity of the injury depends on the nature and force of the trauma, and may range from simple sprains to the ligament, with stretching of the tissue, to a complete tear of the ligament. A ligament may be injured in isolation, or as part of a combined injury termed a “multi-ligament knee injury.” Multi-ligament injuries are generally severe injuries that result from a dislocation of near-dislocation (termed “subluxation”) of the knee and may involve damage to other structures, such as ligaments or nerves around the knee.

Symptoms

Symptoms of knee ligament injuries involve pain at the time of the injury, with further stress on the knee. The knee may become swollen and bruising may occur. With severe injuries the knee will feel “unstable’ and the patient will be unable to bear weight.

Diagnosis

Diagnosis of knee ligament injuries involves review of the patient’s history of the injury and symptoms, as well as a physical examination of the stabilizing structures around the knee. X-rays are reviewed to look for associated fractures and to look for signs of knee instability. A MRI scan provides detail on the extent of the injury and involved areas. Additional studies may be required outline complex fractures (CT scan) or to look for injury to blood vessels around the knee (arteriogram).

Treatment

Treatment of knee ligament injuries depends on many factors including the nature and extent of the injury, areas of the knee involved, and the age and activity-level of the patient. Mild sprains may be treated with rest and bracing of the knee, crutches and limited weight bearing movement, icing, and pain medicines, followed by physical therapy to restore normal strength and motion of the knee after the injury has healed. More severe injuries that involve complete tears – particularly multiple ligament injuries – often require surgery to repair or reconstruct ligaments and restore stability and function of the knee. These may be extensive and complex surgeries and may even require a “staged” approach with more than one procedure. Dr. Boes will review the details of your particular injury with you and discuss the treatment processes.

Additional Information

For more information, visit http://orthoinfo.aaos.org/topic.cfm?topic=A00551.