The posterior cruciate ligament (PCL)connects the femur to the tibia at the back of the knee. It limits the backward or posterior motion of the tibia (shinbone). Twisting or overextending the knee can cause the PCL to tear, leaving the knee unstable and potentially unable to support a person's full body weight. The PCL is the strongest ligament in the knee, and tears often are associated with traumatic injuries rather than sports injuries. PCL tears can happen when the knee is violently forced backward or when the front of the shin is hit hard, for example when the knee strikes the dashboard during a car accident.
Since PCL tears usually result from a violent blow to the knee, they are often accompanied by injuries to other knee ligaments. Although rare, PCL tears can occur when playing rugby, football or other contact sports.
PCL Tear Diagnosis
POSTERIOR DRAWER TEST, where DOCTOR pushes the shinbone or tibia back while the knee is bent 90 degrees. If the tibia moves more than five millimeters backward, it is likely that the PCL has been torn. Your doctor may perform other maneuvers to test for PCL insufficiency as well.
- X-ray: to rule out any fractures.
- Magnetic Resonance Imaging (MRI): This is an effective tool (with an accuracy rate of nearly 90 percent) for determining whether a PCL has been torn and to assess the extent of the damage.
- Arthroscopy: During this test, the doctor inserts a tiny camera( ARTHROSCOPE) into your knee. This is the best way to examine a partial tear for it allows your doctor to gently pull at the PCL and determine the extent of the damage. This procedure is done on day carebasis and is relatively pain-free.
Signs and Symptoms
Symptoms of a PCL tear can vary; the most obvious include pain, swelling and a feeling of unsteadiness in the knee.
For all grades of PCL sprains, initial treatment follows the RICE rule:
- Compression the swelling with an elastic bandage.
- Elevate the injured area
Your doctor may also recommend a non steroidal anti-inflammatory drug (NSAID), such as ibuprofen (Advil, Motrin and others), to relieve any mild pain or swelling.
After initial treatment with RICE, further treatment of PCL sprains depends on the grade of the injury:
- Grade I and Grade II PCL sprains9(PARTIAL TEAR) - Your knee IS splinted in a straight-leg position, and you'll begin an intense rehabilitation program. This rehabilitation gradually strengthens the muscles around the knee (especially the quadriceps), supports the knee joint and helps to prevent the knee from being injured again.
- Grade III PCL sprains(COMPLETE TEAR) - if the PCL has been pulled away from the bone, surgery may be recommended to reattach it with a screw. If the PCL is torn completely, it can beIS reconstructed surgically using either a piece of your own tissue (auto graft) or a piece of donor tissue (allograft). With an auto graft, the surgeon typically replaces the torn PCL with part of your own patellar tendon (the tendon below the kneecap) or a section of tendon taken from a large leg muscle(HAMSTRING TENDON). Almost all these surgeries are performed using arthroscopic (camera-guided) knee surgery, which uses smaller incisions and causes less scarring than traditional surgery. After surgery to reconstruct the PCL, you'll wear a long-leg knee brace and gradually begin a rehabilitation program to strengthen the leg muscles around the knee.