Cruciate Ligament Injury

Overview

Around the knee are important ligaments that attach the femur to the tibia. These two ligaments are known as the anterior cruciate ligament, or ACL, and the posterior cruciate ligament, or PCL. These two ligaments create the shape of an ‘x’ over the knee to stabilize the leg. A tear in either of these ligaments can cause pain and require weeks or months of rehabilitation and rest.

Causes

Causes of injury to either the posterior or anterior cruciate ligament happen for a variety of reasons, including:

• Sport injury: When a foot is planted into the ground and a twisting motion is directed to the knee, ligaments can tear. Direct contact to the knee area during a physical activity can also cause the posterior or anterior ligament to tear. Stretching or bending in an unnatural position can place strain on the two ligaments, resulting in a tear.
• Car accident/trauma: In some cases, impact during an accident can cause the knee to strike the front dashboard or seat, causing the knee ligament to slightly pull from the shin and tear.

Symptoms

An anterior cruciate ligament injury has the following symptoms:

• Feeling of instability and swelling directly after the tear
• Extreme pain in the knee area
• Swelling around the knee and tenderness
• Limited mobility, unable to extend the leg

A posterior cruciate ligament injury is indicated by the following symptoms:

• Moderate pain in the knee area
• Swelling around the knee within one to three hours, and tenderness around the area
• Pain around the knee when squatting down, and difficulty when walking
• Little to no initial pain, gradually becoming more painful to walk or apply pressure to the knee as time passes

Diagnosis

A tear in either ligament can be diagnosed with the following tests:

• Magnetic Resonance Imaging (MRI)
• X-ray
• Arthroscopy - A small camera inserted through a small incision to get an up-close look at the joint

Treatment

Treatment of a posterior cruciate ligament tear can often be done with pain relievers, such as naproxen or ibuprofen. As the knee recovers, a doctor may suggest physical therapy to strengthen the knee and surrounding ligaments. With a minor tear in the anterior cruciate ligament, it is important to rest the knee immediately and use the RICE method:

• Rest
• Ice
• Compression
• Elevation

Surgery

With severe tears, especially in the anterior cruciate ligament, surgery may be required to stitch the ligament back together. Reconstruction of the ligament may also be done to re-establish the ligament to the thigh and shin bones.