What is the Posterior Cruciate Ligament (PCL) Injury?
The posterior cruciate ligament is a band of fibrous tissue located towards the back of the knee. It is one of the four main ligaments in the knee and prevents excessive movement of the knee joint.
How does it get injured?
Most commonly PCL injuries are caused by direct trauma to the knee, classically the ‘car dashboard injury’ where the lower leg is forced backwards at the knee with the foot bent downwards, rupturing the PCL. This same mechanism can occur in a fall or during contact sports.
What symptoms would I have?
The symptoms patients report are variable. Often at the time of injury there was pain at the back of the knee, though this can settle quite quickly. Going down stairs and running may cause pain, often behind the knee cap, and there may be a feeling of instability from the knee. Often patients feel that they cannot trust their knee, due to the instability.
How would it be diagnosed?
During your orthopaedic consultation, history and examination findings would help with the diagnosis especially a posterior draw test where your PCL will be gently stressed by the surgeon pushing your shin bone (tibia) backwards with your knee bent. If the PCL is deficient or torn, the tibia will slide too far backward. Imaging techniques including X-rays and MRI would be used to assess the PCL and also to identify other knee problems.
How is it treated?
Initial treatment of the pain and swelling consists of the use of crutches, ice, and elevation. Once these symptoms have settled, physiotherapy is used to maximise knee strength and stability, whilst teaching you to avoid positions and movements that would worsen your symptoms.
The severity of the tear can be graded, with lower grades (I and II) doing well without surgical intervention.
If other knee ligaments have been injured, and/or if conservative treatment has not worked, then reconstruction of the PCL is indicated. Surgery involves removing the damaged PCL, and reconstructing a new one using grafts, typically using segments from your own hamstring muscles.
When would I get back to normal?
Most people return to their normal daily activities in 2 weeks, and return to sport at 6 months after surgery.