An ACL injury is the most commonly seen injury to the knee. ACL injuries are a common sports injury with a worldwide reconstruction rate of more than 200,000 per year. Significant damage to the ACL can cause detrimentally abnormal biomechanical structure to the knee, which if undiagnosed incorrectly could affect the player’s career. The ACL is an extremely complex structure and has numerous structural differences throughout the ligament. The ligament originates from the femur and attaches onto the tibia, its predominant role is to act as a primary stabiliser against extreme rotational and hyper forces in the knee. The ACL has two components both that compliment the knee when it is in knee flexion and knee extension.
A typical mechanism for an ACL injury is a twist with the foot fixed to the ground, causing extreme rotational forces through the knee. The patient/player will most usually feel and or hear a “pop”, “click” or “clunk” this is this sound of the ACL rupturing. This is usually followed by severe pain and an unwillingness to bend and or straighten the knee joint.
At this stage, ice and compression should be applied immediately and try not to walk on the affected knee. This can be achieved using crutches. Continue to ice and compress the knee for as long as you can over the coming days and seek medical advice immediately.
There are several tests that a Physiotherapist or Doctor will complete when testing for an intact ACL.
-The Lachmans Test
-The Anterior Drawer test
– The pivot shift test
These tests will confirm if you have an “intact” ACL, if you do not, most patients/players undergo surgery to repair the ACL ligament. Surgeons will most commonly only operate when the knee has minimal swelling and the patient/player can bend the knee to over 90 degrees of knee flexion. From injury to return to sport, recovering from an ACL injury usually takes anywhere from 6-12 months dependent on how the body reacts to the swelling and how it copes after the operation. After the operation, patients/players will undergo 6-9 months of rehabilitation. This period involves learning to walk again, learning to jog again, strength training, functional movements that for example involve moving with a football/rugby ball or netball.
The recovery rate for ACL injuries is high and most patients return to sport again, gone are the days of having to retire from these injuries!