What is the PCL?
The posterior cruciate ligament (PCL) is one of several ligaments in the knee that joins the upper and lower parts of the legs together. Its function is to provide stability during twisting or turning movements of the knee, particularly when the knee is bent. It is infrequently injured.
What causes PCL rupture?
The most common way for the PCL alone to be injured is from a direct blow to the front of the knee while the knee is bent, for example a “dashboard” injury during a car accident in which a blow occurs to the front of the lower leg. This forces the lower leg backwards at the knee, rupturing the ligament. The same force can occur during a fall on the bent knee, or during a football tackle. Tears of the PCL can also result from an injury that over extends or over flexes the knee.
What are the symptoms?
There is a wide range of symptoms. Some patients are able to function normally with the assistance of physiotherapy in the acute stage of the injury, while others present with pain, an inability to run or an unstable knee that gives way with sidestepping. Once the acute injury settles some patients may experience pain behind the knee cap or at the back of the knee itself. Activities such as running and going down stairs may be difficult or painful. Occasionally patients describe episodes of the knee giving way during activity or a feeling of insecurity within the knee.
How are PCL tears diagnosed?
Like most knee conditions, a history of the injury and clinical examination should enable a diagnosis to be made. Often an MRI is performed to confirm the diagnosis, but more importantly to allow assessment of other knee injuries.
Can PCL tears be treated without surgery?
Patients with a ruptured PCL who are content with activities that require little in the way of side stepping (running in straight lines, cycling and swimming) may opt for conservative treatment.
Conservative treatment includes physiotherapy to reduce swelling, restore the range of motion of the knee joint and rehabilitate to full muscle power. Proprioceptive training to develop essential protective reflexes are required to protect the joint for normal daily living activities.
What operation may be beneficial?
All reconstructive procedures for the PCL require a graft. Segments of the hamstring tendons are used for an isolated PCL reconstruction. Other graft materials may be used if multiple ligaments are torn. Specially designed screws are used for secure immediate fixation of the tendon within the joint allowing for a more rapid rehabilitation and dispensing the need for a brace or plaster.