Posterior Cruciate Ligament (PCL) Injuries and Tears
The posterior cruciate ligament or PCL connects the femur to the tibia and is located in the back of the knee. The PCL ensures the shinbone does not move too far backward.
The PCL is not as commonly injured as the anterior cruciate ligament or ACL, because the PCL is relatively thicker and stronger. In fact, because of the location, structure and strength of the PCL, injuries are often less obvious and require a more in-depth diagnosis. PCL injuries most often occur alongside other injuries including cartilage/meniscus tears, bone fractures and other ligament tears.
Typically, PCL injuries occur due to a strong blow to the knee area. This often occurs during sports, strenuous activity or during a serious accident such as a motor vehicle crash. However, even a minor injury during day-to-day activity can result in a sprain of the PCL.
Types of PCL Injuries
- A grade 1 sprain is where the PCL is only slightly injured and stretched. There may be some pain and associated swelling, but the PCL retains its ability to stabilize the knee joint.
- A grade 2 sprain is often called a partial tear and as a result, the knee joint becomes loose and sometimes unstable.
- A grade 3 sprain is known as a full tear. This occurs when the ligament actually splits in two and the knee joint is completely unstable.
Signs and Symptoms of a PCL Injury
As mentioned above, PCL injuries are somewhat more subtle than their ACL-related counterparts. We will take your medical history as well as performing a physical examination to see the range of motion of the knee and how and when the area becomes painful.
Diagnostic imaging will also be useful in the diagnosis. We will begin with an x-ray to examine the bony structures of the knee joints. While the x-ray does not show soft tissue, we can see if the ligament has pulled off a piece of bone, known as an avulsion fracture. We will then follow this test with an MRI to evaluate the soft tissue.
Treatment for PCL Injuries
Most times a PCL injury can be treated non-surgically. Because of the strength of the ligament, this is often possible, unless it is torn and/or surrounding structures are damaged as well. Nonsurgical treatment will include rest, ice, compression and elevation which is critical for any soft tissue injury. You may also need a brace or splint to help stabilize the knee and stop additional damage. All non-surgical treatments will be followed up with physical therapy to improve range of motion and strengthening associated musculature.
Surgical Treatment for PCL Injury
Surgical treatment for a PCL injury may be necessary for significant injuries such as a grade 3 sprain of the PCL or if you have combined injuries with cartilage and/or bone. Surgery typically involves rebuilding the PCL, as a suture repair is rarely successful. This involves replacing the torn ligament with tendon or ligament tissue harvested from another part of the body or from a donor. This is very similar to ACL reconstruction.
Virtually all PCL reconstruction is performed using arthroscopy, a minimal invasive surgical technique that requires only tiny tools and incisions versus the larger incisions of the past. A miniature, fiber-optic camera allows your orthopedic surgeon to visualize the surgical field. The minimally invasive nature of this technique allows for a shorter and less complicated recovery.
Physical therapy will be a critical part of rehabilitation for surgical reconstruction of the PCL. Physical therapy may begin any anywhere from a few days to a few weeks after surgery. The length of therapy will depend on the injury itself and whether there are other associated injuries such as those to cartilage or bone.
The prognosis for a PCL injury is similar to that of other ligament injuries and ultimately is very good. Patients who follow their postoperative recovery plan closely have the best chance of regaining their prior mobility and eliminating nagging pain, stiffness and muscle weakness associated with the injury.