The anterior cruciate ligament, or ACL, helps stabilize your knee when you perform an activity. Without it, the knee can easily buckle. This stability from the ACL is vital to functional mobility.
Another key part of the ACL’s role is to provide input to the brain, something that is often forgotten. Inside a fully functioning, non-damaged ACL are nerves called proprioceptors. These tell the brain where the knee is in space and if the joint is moving or staying still. When an ACL is torn, these nerves no longer function. The brain is no longer receiving input from the ACL.
During a rehabilitation process, it’s common to focus on your knee when performing exercises. This causes a visual link between the knee and its mechanics. The eyes tell the brain where the knee is, and if it’s moving or stationary. This is fine for when a person is working out in the gym or in another quiet and distraction-free setting.
However, when a person with an ACL reconstruction steps back onto the playing surface, their eyes are no longer focused on what their knees are doing. The eyes are distracted, the brain is no longer receiving the proprioceptive input that it needs and the knee may become less stable. This creates a huge concern for re-injury to the reconstructed ACL.
Because of this, if you’ve suffered an ACL injury, it’s important to perform therapy and exercises with a physical therapist that is going to help your brain and knee work independently of visual stimulation. It’s important to find a trained, qualified therapist to help guide you through your ACL reconstruction rehabilitation.
Jacob Hart, D.P.T., is a full-time physical therapist at MidMichigan Medical Center – Mt. Pleasant with special interests in sports medicine, injury prevention and orthopedics.