Anterior Cruciate Ligament (ACL) 

Technical Name: Anterior Cruciate Ligament rupture 

AKA Name: ACL rupture/Cruciate tear

Short Summary:

There are 4 main knee ligaments.  Two of these are within the central knee space - the anterior and posterior cruciate ligaments - both of which help to stabilize the knee when it is moving normally.   When one of these ligaments tears (most commonly the anterior ligament), the knee can become unstable or give way with movements such as twisting or with sporting activities.   

What is an ACL tear/rupture?

An injury to the anterior cruciate ligament (ACL) classically occurs with a sudden change of direction whilst jumping or landing associated with a twisting force to the knee.  This usually happens during sports such as football, rugby, netball or skiing where your body twists while your foot remains in a fixed position.   

What are the symptoms?

At the time of the injury patients often describe hearing a ‘snap’ or a ‘pop’ as the knee collapses.  There is usually rapid painful swelling of the knee within a few hours of injury and it may be difficult to put weight through the leg or move it properly.  The function will then improve gradually over a few weeks as the swelling settles, but you may experience a feeling of the knee not feeling secure with a sense of it wanting to collapse or give way under you.  This may be worse with any form of rotatory or twisting movement.  

How is it diagnosed?

A detailed history of the event is important in conjunction with a full assessment of the stability of your knee.  An MRI is normally arranged to confirm the diagnosis and identify the extent of any associated damage within the knee, such as a cartilage tear or bone bruising.

How is it treated?

ACL injuries can be treated with or without an operation.  In all cases specific physiotherapy is started to strengthen muscles around the knee and regain a full range of motion.  This can take several weeks.  After undertaking a specific ACL injury rehabilitation programme, some patients regain sufficient stability and coordination to be able to return to their desired level of function.  This is less likely in those that wish to return to competitive twisting sports, and if instability symptoms persist then ACL reconstruction surgery should be considered.     

Important: this information given above is only a guideline as is not complete.  For more information or to book an appointment please contact us.