ACL Injury

One of the most common ligament injuries occurring in the knee is an ACL tear. The anterior cruciate ligament (ACL) is the primary ligament preventing the tibia from coming forward underneath the knee. It is the most important stabiliser of the knee.


What Causes an ACL tear?

ACL tears normally occur whilst playing sport. It is often a non- contact injury, The ACL is usually injured in landing flat on the heel or rapid deceleration followed by a sudden change in direction.

What are the symptoms of an ACL tear?

Significant pain and swelling in the knee occur immediately after the injury. You may feel unstable like your knee wants to give way from under you.


Treatment for ACL tears

Although you can live without an ACL, it is recommended for most people to undergo ACL reconstruction surgery.


Will you need an operation for an ACL tear?

Pain and swelling will start to settle following injury. However, as time goes on the knee might start to feel unstable or give way.


A few factors that may influence your decision to undergo surgery include:

  • Regular participation in sport or physical activity requiring changes in direction
  • Frequency of episodes of giving way i.e. the degree of instability
  • Associated injuries
  • Patient goals and expectations


Before surgery, Physiotherapy aims to restore pain- free range of movement and strengthen the knee to prepare it for surgery and post- surgical outcome.


Rehabilitation following surgery is importing in restoring full range of movement, strength, proprioception and knee motor control. Thorough rehabilitation tailored to your sport of choice will help with your transition back into sport. Every patient should be discharged with the PEP Program developed by the Santa Monica Sports Medicine Foundation. The program has been shown to reduce the risk of ACL injury and prevent a second injury, Gilchrist et al (2008).


If you decide that surgery isn’t for you, Physiotherapy can help restore pain- free range of movement with capacity to return to normal activity through soft tissue releases, knee motor control and strengthening exercises, stretches and proprioceptive exercises.


Your Physiotherapist will discuss your treatment goals and educate you about the condition, the rehabilitation process and preventative methods to reduce the risk of future injury.


To book an appointment with one of our skilled Physiotherapists please call (02) 8068 8832 or email us at [email protected].


Gilchrist J, Mandelbaum BR, Melancon H (2008) A randomized controlled trial to prevent noncontact anterior cruciate ligament injury in female collegiate soccer players. Am J Sports Med.36(8):1476-83


ACL Injury

Injury Description 

The anterior cruciate ligament is the primary stabilising ligament in your knee. It prevents the knee from giving way during twisting, turning and side stepping movement.


The anterior cruciate ligament is usually injured via direct contact, in twisting movements or landing with rapid deceleration followed by a sudden change in direction.



Partial tears of the anterior cruciate ligament is uncommon. Most of the time if the anterior cruciate ligament is torn it is completely torn or nearly completely torn.


Often, the knee swells up very quickly due to bleeding into the joint. It will be painful to walk and there will be restrictions with knee movements. Once the effusion begins to resolve, incidents of the knee giving way may be experienced.



When the ACL ruptures it does not heal by itself. Anterior cruciate ligament reconstructive surgery is required if the patient wants to return to sports or occupations requiring pivoting movements or sudden changes in direction of the knee. Otherwise, a comprehensive rehabilitation program may be sufficient.


With increasing reccurrence of giving way of the knee, surgery should be considered.


The patient is at the highest risk of re- tearing their anterior cruciate ligament in the 1st year following surgery. However, patients should expect to make full recovery and return to normal sporting or work activities provided adequate rehabilitation following surgery.


There is conflicting research studies in predicting risk of developing osteoarthritis following anterior cruciate ligament injury. Having had an anterior cruciate ligament tear may place the patient at higher risk of developing osteoarthritis.



  1. Initial management, if an ACL tear is suspected, should involve ice, elevation and compression bandage. Diagnosis by a Physiotherapist or Doctor, confirmed with an MRI. Physiotherapy treatment can help reduce swelling and improve movement. Prior to surgery, Physiotherapy aims to prehab the knee.
  2. Arthroscopic surgery aims to reconstruct the anterior cruciate ligament. Choice of graft will depend on patient and surgeon discussion.
  3. Physiotherapy for post- surgery rehabilitation aims to regain range of motion, knee strength, proprioception and agility. The goal of physiotherapy is to allow patients to make full recovery to return to normal work and sporting activities.