The cruciate ligaments within your knee is made up of, the Anterior cruciate ligament, ACL and the Posterior cruciate ligament PCL. They attach your femur (thigh bone) to your tibia (shin bone), crossing each other in an ‘X’, this is to provide rotational stability and control the forwards and backwards motion of your knee.
Your Anterior cruciate ligament begins from the back of your tibia and attaches diagonally at the front of your femur. The majority of your tissue sits at the back and is designed to prevent any forwards displacement or internal rotation of your tibia.
ACL injury is most common in younger individuals who play sports that involve pivoting, decelerating and jumping. The mechanism of ACL injuries can be categorised further into contact (30% of cases) or non-contact (70% of cases). Non-contact usually involves short quick changes of direction at high speed during sports. The most common being when the foot is planted on the floor and the torso excessively rotates on top of the knee for example.
How do I know I’ve torn my ACL?
How do you know you’ve torn your ACL. It's difficult to without an assessment by a medial professional and/or imaging. However, here are some signs and symptoms that can give you a pretty good idea:
An audible “snap”, “pop” or “crack”
Immediate pain
Immediate and excessive swelling (although some cases have delayed and sometimes minimal swelling)
Restricted range of motion, particularly in knee extension
Instability and/or incidences of your knee giving way
Torn ACL Anterior cruciate ligament example
What happens next?
Interestingly, not all ACL’s require surgical intervention. Non-operative treatment is preferred. when the individual is older than 35 years old, has little or no anterior tibial subluxation (forward displacement of your shin bone), and is not highly active.
However, In most cases ACL reconstruction is recommended. There are a few ways in which the operation can be done. The most common involving taking a graft from a nearby tissue to rebuild the ACL. These can include: the patellar tendon, the iliotibial tract, the semitendinosus or gracilis tendon.
For the first two weeks following surgery, you will likely be placed in a knee brace that will be locked in place.
ACL Anterior cruciate ligament surgery
How long will my rehab be?
How long is a piece of string? Unfortunately, there is no ‘one-size fits all’ protocol when it comes to ACL rehabilitation. There are many variables that should be considered. This means it is important to find a physiotherapist that understands the process of restoring function to your knee, as well as listening to your goals and what is relevant to you. However, if you are aiming to get back to sport, research suggests that a return before 9 months places you at a higher risk of re-injury.
Your early goals of rehab should include:
Reducing any post-surgery pain or swelling
Restoring full range of motion (knee flexion and extension)
Building up muscle strength that is equal to the unaffected side (both local to the knee and global – hip/calf/ankle)
Regaining stability and improving proprioception of the affected side
If returning to sport, your long-term rehab should include:
Continued strength & conditioning (running, squats, lunges, deadlifts etc)
Acceleration and deceleration drills
Plyometrics (jumping, landing)
Change of direction drills
Take-away:
Nobody wants to be injured, let alone tear their ACL. However, it isn’t the end of the world! Plenty athletes have returned to sport following this type of injury. It is important to find a medical professional that can firstly diagnose and advise your next steps in the niitial stages (whether surgery is required or not). Then find an experienced physiotherapist that understands the rehabilitation process and who can help guide you on your return to sport. Trust and patience in the plan is vital, as an early return to higher level activity can increase the likelihood of re-injury.
