Because pain caused by a PCL sprain is not always extensive, many PCL injuries are often misdiagnosed, which can lead to more damage. If you think you my have suffered a sprain or tear in your PCL, see your doctor immediately.
The posterior cruciate ligament (PCL) is one of four major ligaments of the knee. The PCL is one of the structures that connect the femur (thigh bone) to the tibia (shin bone). Its primary function is to keep the tibia from moving backward abnormally in relation to the femur. When the PCL is torn, active patients may develop a feeling of knee instability or pain. This instability or pain may limit an active lifestyle and may cause injury to other structures of the knee.
Injury to the PCL is much less common than injury to the ACL, the anterior cruciate ligament. The PCL is usually torn by a direct blow to the front of the upper part of the tibia with the knee in a bent position. In football, this may happen when a running back's knee lands directly on the turf. Damage to the PCL is often the result of dashboard-type injuries in motor vehicle accidents. PCL sprains are classified as Grade I (minimal damage), Grade II (moderate ligament damage and partial tearing), and Grade III (complete ligament tear).
A PCL sprain or tear may result in moderate pain. The amount of discomfort, stiffness and swelling that follow a posterior cruciate ligament injury is not always substantial, and many PCL injuries are initially diagnosed as knee sprains. Patients will often have discomfort, especially in the back of the knee when bending it, and the knee may become swollen. Only some patients develop instability in the knee.
Your doctor can detect a PCL tear by learning more about the history of the injury and examining your knee. X-rays cannot be used to detect a tear in the PCL but are often used to identify other problems and injuries to the bones about the knee. A magnetic resonance imaging (MRI) examination may be used to view the PCL as well as other knee structures.
- Rest . All activities that require active use of the knee should be restricted. Talk with your doctor about a plan for gradually returning to full activity.
- Ice . Ice packs may be used for about 20 minutes at a time, each hour to help alleviate pain and decrease swelling.
- Bandage/Compression Wraps . Your doctor may recommend that you use a soft elastic wrap or bandage at the knee to help reduce swelling.
- Elevation . Elevating the knee should help ease pain and swelling. Ideally, the foot should be elevated higher than the knee, and the knee should be elevated higher than the hip.
- Medication . Your doctor may prescribe an anti-inflammatory or pain medication.
- Knee Brace . Your doctor may prescribe a knee brace to help stabilize the joint.
- Crutches . Your doctor may advise you to use crutches to take pressure off the knee, reduce pain and increase mobility. You should be protected with crutches if weight-bearing is painful or if you are limping.
- Physical Therapy . Your doctor or physical therapist may recommend a range of motion and muscle stretching and strengthening program for your knee.
The primary reason for surgical reconstruction of an acute PCL tear is significant looseness in the knee, associated injury to other structures around the knee or the development of instability or activity-related pain within the knee. Patients without other significant knee joint injury, who are willing to modify their lifestyle or do not develop knee instability, may be treated nonoperatively with bracing and physical therapy. It may be recommended that children with a torn PCL delay surgery until after they have stopped growing. Talk with your doctor about whether surgery is the best approach for your injury.
Following surgery to repair a PCL injury, it usually takes a minimum of six months of recovery before you can return to full contact sports. Your doctor may ask you to wear a brace for at-risk activities when initially returning to sports after PCL surgery. Full recovery can easily take 12 months. Recovery time depends in large part on the extent of your associated injuries and the care of your knee during the rehabilitation process.