Considerations

Your doctor will perform a physical examination to check for signs of PCL injury. This includes moving the knee joint in various ways.

Your doctor may also check for the presence of fluid in the knee joint. This test may show joint bleeding.

PCL injury may be seen using the following tests:

• Knee MRI
• Knee joint x-ray

Causes

The posterior cruciate ligament (PCL) is the strongest ligament in the knee. It extends from the top-rear surface of the tibia (bone between the knee and ankle) to the bottom-front surface of the femur (bone that extends from the pelvis to the knee).

The ligament prevents the knee joint from posterior instability. That means it prevents the tibia from moving too much and going behind the femur.

The PCL is usually injured by overextending the knee (hyperextension). This can happen if you land awkwardly after jumping. The PCL can also become injured from a direct blow to the flexed knee, such as smashing your knee in a car accident (called "dashboard knee") or falling hard on a bent knee.

Most PCL injuries occur with other ligament injuries and severe knee trauma. This injury usually occur with a knee dislocation with has a high chance of nerve and vessel injuries. If you suspect PCL injury, it is important to be seen by a medical professional immediately.

Symptoms

• Knee swelling and tenderness in the space behind the knee (popliteal fossa)
• Knee joint instability
• Knee joint pain

First Aid

At first, a PCL injury is treated by:

• Checking the pulse and circuation in the area
• Splinting
• Applying ice to the area
• Elevating the joint (above the level of the heart)
• Taking nonsteroidal anti-inflammatory drugs (NSAIDs) for pain

Limit physical activity until the swelling is down, motion is normal, and the pain is gone. Physical therapy can help you regain joint and leg strength. If the injury happens suddenly (acute) or you have a high activity level, you may need surgery. This may be either knee arthroscopy or "open" surgical reconstruction.

Age has an effect on treatment. Younger patients are more likely to have problems without surgery, because chronic instability may lead to arthritis symptoms many years later. Which patients need surgery is controversial, because many people seem to do well without surgery. Injuries in which the bone is pulled off with the ligament, or multiple ligaments are injured need to be repaired with surgery.

PCL injuries are commonly associated with other ligament injuries or knee dislocation. It is important to have your knee examined for other injuries. Some of these injuries need to be treated urgently.

When to Contact a Medical Professional

Call your health care provider if:

• You have symptoms of PCL injury
• You are being treated for PCL injury and you have greater instability in your knee
• Pain or swelling return after they went away
• Your injury does not appear to be getting better with time
• You re-injure your knee
• You have loss of sensation and decreased in circulation in your foot

A lot of PCL injuries are associated with other ligament injuries or severe knee trauma. You should be checked early for these other conditions.

Prevention

Use proper techniques when playing sports or exercising. Many cases are not preventable.

Alternative Names

Cruciate ligament injury - posterior; PCL injury; Knee injury - posterior cruciate ligament (PCL); Hyperextended knee

References

Honkamp NJ, Ranawat AS, Harner CD. Knee: Posterior cruciate ligament injuries in the adult. In: DeLee JC, Drez D Jr, Miller MD, eds. DeLee and Drez’s Orthopaedic Sports Medicine. 3rd ed. Philadelphia, Pa: Saunders Elsevier; 2009:chap 23, section E.

Honkamp NJ, Ranawat AS, Harner CD. Knee: Posterior cruciate ligament injuries in the child. In: DeLee JC, Drez D Jr, Miller MD, eds. DeLee and Drez’s Orthopaedic Sports Medicine. 3rd ed. Philadelphia, Pa: Saunders Elsevier; 2009:chap 23, section E.

Update Date: 4/4/2012

Reviewed by: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.