What is the PCL?
The PCL ligament is the largest and strongest ligament in the knee and the primary knee stabilizer. It is located in the back of the knee. It is comprised of 2 bundles of fibers that work together to resist backward movement of the tibia (shinbone).
What causes a PCL tear?
Tears are usually the result of trauma, such as an auto accident where a bent knee is forced into the dashboard during an auto accident. In sports an isolated PCL tear is the result of a direct blow to the knee or a fall on a bent knee. The highest incidence of PCL tears occurs football, soccer, rugby and skiing. Most PCL injuries are diagnosed in people aged 18-44 who suffer a sports injury; but people who perform manual labor that requires frequent squatting and heavy lifting are also at risk. Older adults can suffer a ligament injury due to normal wear and tear, and from a previously undiagnosed PCL injury.
Grades of PCL tears
PCL injuries are much less common than tears to the anterior cruciate ligament; and injuries to the PCL often occur along with damage to other knee ligaments, bone and knee cartilage. Tears may be acute from trauma or chronic. Chronic tears develop over time.
Tears are graded from mild to severe:
- Grade 1 is a partial tear or stretching of the PCL, but the knee remains stable
- Grade 2 is a partially torn ligament that is looser than a grade 1 tear
- Grade 3 is a complete tear of the PCL, and causes knee instability
- Grade 4 is a PCL tear combined with damage to another knee ligament.
Most PCL tears are Grade 1 and have the potential to heal. When healed the patient is often able to return to sport without knee instability.
What are the symptoms of a PCL tear?
The most common symptoms are sharp pain and swelling, knee stiffness that causes limping, and difficulty walking or putting weight on the damaged knee. Severe PCL tears can cause instability. Because PCL tears are often less painful and causes less instability than injury to the anterior cruciate ligament, they may be overlooked.
How is a PCL injury diagnosed?
Dr. Cooper will ask about how and when your knee was injured and inquire about your symptoms. He will conduct an examination of the injured knee and perform certain range of motion tests testing normal knee movements. He will order x-rays to view the bones to detect bone damage caused when the ligament was pulled off the bone. An MRI will be ordered to identify the size and location of the tear. When chronic injuries are suspected, he may order a bone scan to evaluate bone damage.
What are the treatment options for a PCL tear?
Severe PCL tears (grade 3 tears) usually require surgery especially when other knee structures are also damaged; and when the knee remains unstable after conservative treatments. Most less severe tears can heal with conservative management including rest, ice, compression, elevation, and OTC anti-inflammatory medications, bracing, crutches and physical therapy. In some cases, Dr. Cooper may recommend regenerative treatments such as platelet rich plasma which is injected to facilitate healing. Recovery without surgery generally take weeks to a few months.
PCL surgery, like ACL surgery, involves arthroscopic ligament reconstruction with an autograft of a tendon from the patient, or from a donor. Recovery after surgery depends on the severity of the PCL tear and the extent of repairs performed for damage to other knee structures.