PCL Tear

The knee is one of the most complex joints in the human body. It relies on several ligaments to stay stable and allow movement. The posterior cruciate ligament (PCL) is one of these important ligaments. It runs through the center of the knee, connecting the thighbone (femur) to the shinbone (tibia) at the back of the knee.

The PCL works alongside the anterior cruciate ligament (ACL) to prevent excessive movement of the knee joint. While the ACL prevents the shinbone from sliding too far forward, the PCL does the opposite—it stops the shinbone from moving too far backward. The PCL is a stronger and thicker ligament than the ACL, making PCL injuries less common than ACL tears. However, when a PCL tear does occur, it can significantly impact knee stability and function.

A PCL tear occurs when the ligament is stretched or torn, usually due to a direct impact or a forceful movement. PCL injuries are classified into grades, depending on their severity.

• A grade 1 tear means the PCL is stretched but not torn.
• A grade 2 tear means the ligament is partially torn, leading to some knee instability.
• A grade 3 tear means the PCL is completely torn, often causing severe instability.
• A grade 4 tear occurs when the PCL is torn along with damage to other knee structures, such as the ACL or meniscus.

While mild PCL injuries may heal with time and physical therapy, severe tears may require medical intervention to restore knee function.

PCL tears most often occur due to direct trauma to the knee.

• One of the most frequent causes of PCL tears is a dashboard injury in a car accident. When the knee hits the dashboard during a crash, the shinbone is pushed backward, putting extreme stress on the PCL.
• Contact sports like football, soccer, and basketball carry a risk of PCL tears, particularly when a player falls hard on a bent knee or collides with another player.
• A hard fall onto the knee, such as slipping on ice or falling from a height, can cause a PCL tear.
• Sudden, forceful twisting of the knee can sometimes lead to a PCL tear, especially when combined with other ligament damage. Because the PCL is stronger than the ACL, injuries often require a significant force to tear it.

The symptoms of a PCL tear vary depending on the severity of the injury. In some cases, individuals may not immediately notice a problem, especially with mild sprains. However, as swelling develops, symptoms become more noticeable.

Common symptoms include pain in the knee, especially at the back of the knee, swelling that often appears within hours of injury, stiffness and difficulty bending the knee, instability or the feeling that the knee is giving out, difficulty walking or bearing weight, and bruising around the knee. For partial PCL tears, symptoms may be mild, leading some individuals to believe they only have a minor knee sprain.

Untreated PCL injuries can cause ongoing instability and long-term knee problems, so it is important to seek evaluation from a specialist like Dr. David Gazzaniga if a knee injury occurs.

Diagnosing a PCL tear involves a combination of medical history, physical examination, and imaging tests to assess the knee’s stability and rule out other injuries. Dr. Gazzaniga will begin by asking about how the injury occurred, what symptoms are present, and whether there have been any prior knee problems.

• A physical examination will include checking for swelling and bruising, evaluating range of motion and stability of the knee, and performing specific tests where the doctor pushes the shinbone backward to see if it moves abnormally.
• To confirm a PCL tear, imaging tests may be necessary. X-rays cannot show ligament tears, but they help rule out fractures or other bone injuries. An MRI provides detailed images of the PCL and surrounding structures, allowing Dr. Gazzaniga to see if the ligament is torn and determine the severity. In some cases, a stress X-ray may be used to measure how much the shinbone moves backward compared to the uninjured knee. Once the diagnosis is confirmed, a treatment plan can be developed based on the severity of the injury and the patient’s activity level.