Tearing your Anterior Cruciate Ligament (ACL) has long been considered one of the worst injuries for a sports person to suffer. It typically means a long time away from sporting activity, more often than not having surgery and a lengthy rehabilitation. I have never enjoyed telling a patient that they have torn their ACL because I know the long road ahead.
What is the ACL?
The ACL is a strong ligament in the knee that prevents exceed rotational loads and anterior movement of the tibia on the femur. It provides about 85% of the total restraining force of anterior tibial translation, which means it can be under significant load when playing sport where pivoting and quick stopping are required.
Tear of the ACL?
A tear to the ACL can happen when an athlete is pivoting and often happens when they are not near the actual play. You can have a partial tear or a complete rupture of the ligament. Common symptoms at the time of injury are that the athlete will hear a pop and the knee will feel very unstable. The athlete will generally be unable to continue playing. Swelling in the knee usually starts quite soon after the injury.
Other structures such as the meniscus and other ligaments are often injured at the same time and this can complicate the rehabilitation.
Treatment options?
For as long as I have been a physio and for a long time prior to this, ACL reconstruction was the only choice if an athlete wanted to resume playing sport. It was considered that an ACL deficient knee was too unstable to play sports that involved pivoting such as football and netball. It was also considered that an ACL deficient knee would lead to early onset of osteoarthritis and increase the risk of injuring other knee structures. The ACL was also thought to never be able to heal!!
Recent research has shown that ACL tears can actually heal up. The KANON trial showed "Following management with rehabilitation-alone at 5-years (n=26), 56% had a healed-ACL at 2-years and 58% at 5-years."
Some people can actually also return to sport without an ACL. These people have a clinically stable knee. Over the years I have seen 5 people return to sport at a reasonably high level with an ACL deficient knee.
ACL Reconstruction
As mentioned earlier reconstruction of the ACL has been the main method of management of ACL tears for a long time. The orthopaedic surgeon will usually perform this arthroscopically and it is only a day procedure. A graft is taken (hamstring tendon or patellar tendon) from yourself or a donor and fixed into place to replace the torn ligament. Research has shown that the best time to have an ACL reconstruction is when pain and swelling have subsided and there is full range of motion in the knee.
Post op, we want to see you within the first week after surgery to begin the rehabilitation process. Your physio will provide manual therapy and guide you with exercises aimed at increasing range of motion and improving muscle strength. At certain time periods we know that the new ligament is able to withstand certain loads, so we will increase your exercise difficulty each time we pass those timeframes. Eventually you will be performing lots of functional exercises, returning to running, training and eventually to sport when cleared to do so.
Conservative Management of ACL tears
Rehabilitation rather than surgery to repair ACL tears is becoming more common with a growing body of evidence that surgery is not the only option. Rehabilitation can start straight away and can actually reduce the time to return to activity.
Success of conservative management is dependent on the knee being stable enough to withstand the loads that the individual patient needs for their activities. Those patients with a stable knee are more likely to succeed with conservative management than those with an inherently unstable knee.
Case Study
Recently we saw a young man who tore his ACL playing sport. He was due to start an apprenticeship soon after the injury and wasn't keen on having time off right at the start of his career. A joint decision was made to start conservative management, with the option down the track of having surgery at a time that suited.
Several months down the track, this patient has a stable knee and has successfully returned to running and cutting activities related to his sport. He will return to training soon and sport later this year. He has not had any episodes of instability during his rehabilitation which augurs well for a positive outcome.
More recently a young lady has torn her ACL, again playing sport. She has opted to have a knee reconstruction as her knee is unstable with twisting movements.
What can we take away from this?
Not every ACL rupture needs to have surgery
Not every ACL rupture can be treated conservatively
Our physios will help you decide on the best course of action for your knee
Whichever way you go, there is long rehabilitation process to get you back to the activities that you want to be able to do.
