For many years it has been widely accepted that the best treatment of an ACL rupture is immediate surgery to ‘reconstruct’ the torn ligament. This view is so common-place that many people believe surgery is their only option if they wish to return to playing competitive sport after an ACL injury.
Historically; doctors, physios and other health professionals have also held this view, and it has shaped our approach to ACL injuries for years. This has been based around the assumption that the ACL cannot heal on its own, and that a knee without an ACL would be too unstable to return to playing sport. In reality, there has never been solid evidence to support these assumptions, and recent research is actually beginning to challenge these theories, to the point where we are rethinking our whole approach to ACL injury management.
In fact, if you dig a little deeper, you’ll find small research studies as far back as the 90s showing that not only does the ACL have a capacity to heal, but also it is possible for athletes to have a really good recovery and return to sport without having surgery. Unfortunately, given that surgery has historically been considered the best (if not the only) option, the majority of ACL research over the years has focused on ways to improve surgery and post-surgery recovery, rather than investigating other options. However, throughout the 2000s more and more of these small studies began popping up, investigating ACL healing and whether returning to sport without surgery is a valid approach.
Now, the wheels turn slowly when it comes to medical research, and a handful of small studies is not enough evidence to dramatically change an already ingrained treatment approach. However, a research study conducted in Sweden back in 2010, known as the KANON Trial, began to turn the tide. It was the first of its kind; a larger, higher-quality study (called a Randomised Controlled Trial) that compared people who had immediate ACL reconstruction surgery, to people who began with a rehab program and had the option of having surgery down the track if needed. Interestingly, less than half (39%) of the rehab patients opted to have surger, with the other 61% doing well with just their rehab program. They tracked all of the patients for 2 years and used lots of different tests and questionnaires to compare the function of their knee, their knee symptoms and the percentage of people returning to sport. They essentially found that on average, the people that had immediate surgery were no better off than either those who didn’t have surgery at all, or those that initially started with a rehab program but opted for surgery down the track.
This was the first really solid piece of evidence we had to suggest that going straight in for surgery is not the only option, and is potentially even the wrong choice for some people. It paved the way for more research into the topic, including studies that built directly off the work of the KANON trial. The most notable of these actually came from an Australian physio and researcher, Stephanie Filbay. She used the same group of people from the originally KANON trial and did more testing with them down the track. Using MRI to investigate healing in the knee, she found that in 30% of the people who did not have immediate surgery their ACL had healed on its own, just by doing the standard rehab program (this equates to 53% of the people who still had not had surgery at the 2-year point). Not only did this support the notion that the ACL can heal itself, but she compared their other testing results, and found that overall, these people tended to have a better recovery than not only the people whose ACL had not healed, but also the people that had surgery.
These findings give us hope that if we can find a way to support to ACL after injury and increase its chance of healing; then not only does avoiding surgery become a very viable option, it may even become the obvious choice with better results than surgery. This leads us to the question of bracing. With most other ligament injuries in the body, standard practice for larger tears is to immobilise the area for a period of time to give your body the best chance possible of healing on its own – so now that we know the ACL can heal, why don’t we try this? There’s been various studies exploring this concept in recent years, all with relatively positive results. An exciting recent one came again from Dr Filbay, who used what we know about the anatomy of the ACL to develop a bracing program she called the Cross Bracing Protocol, which essentially holds the knee in a bent position for a period of time to give the ACL the best chance of healing. The exciting part is that 90% of the people she trialled her program on showed evidence of ACL healing on follow-up MRI studies. Now again this was a relatively early-stage style of study, but it is a really positive starting point. They also found interesting trends between the type of ACL rupture and how well it healed which could give us extra information for down the track too.
Realistically, a lot more research has to be done before we can confidently say what is the absolute best way to manage an ACL rupture, but there is a mounting body of evidence to suggest we should already be rethinking our blanket approach to surgery. Either way, it is clear we need to get better at managing these injuries so people have a better overall recovery, so it will be interesting to see where further research takes us in the coming years, particularly with trials of bracing techniques.
