Beyond Surgery: The Growing Evidence for Non-Surgical Approaches to ACL Injuries

ACL tears are a common injury in the more active subgroup of society. Management of ACL injuries usually consists of early surgery, with a following prescription of physical therapy. But is this how it is supposed to be? Does this actually provide the best outcome?

In this blog, we’ll dive deeper into the most recent evidence on the non-surgical management of ACL tears, the concept of ACL healing, and the importance of shared-decision making. If you want to learn more about this fascinating topic, make sure to check out Kieran Richardson’s excellent Masterclass on Non-surgical Managment of ACL Tears.

ACL reconstruction rates are very high in most western countries. But one small part of the western world stands out because of their high rate of non-surgical management. Scandinavian health-care models require patients to go to a non-surgical orthopedic specialist first. After a thorough examination, the majority of the patients undergo the “physio first”-route, which leads to fewer surgeries.

The physio first approach

The concept of physio first isn’t something that’s new to this world. In 1994, Daniel and colleagues already proved that there are a lot of patients that do well without surgery. In the 1980’s, prospective studies showed that some patients actually do need surgery while some can cope very well without. That leaves the following question: can we identify who becomes a coper?

It turns out we can, but only if enough time goes by. If you give patients long enough, about 6-12 months, the majority can become copers. However, we cannot predict early on who’s going to do well. Luckily, there are some objective markers that can be used to identify copers. Patients with less than one episode of giving way, who score >80% on a 6m timed hop test, >80% on the KOS ADL subscale and have a >60% global rating of knee function tend to do well in the long run.

Surgery vs conservative care

One of the most high-quality and elaborate studies on ACL management, the KANON trial, compared outcomes between individuals that received early surgery, followed by physical therapy, to people who received supervised exercise therapy first, with the option of having a delayed reconstruction if necessary. They concluded that the first option was not superior to the latter and even described poorer outcomes in the group that had early surgery. However, they did notice a lot of participants crossed from rehab to surgery because of beliefs.

Nowadays, there still is a strong bias towards early surgery, as people think it is necessary in order to go back to normal training and to obtain a better outcome. This shows how important mindset and psychology is to secure a good outcome and highlights the value of education during rehab. One thing remains sure, both surgical and non-surgical management come with risks and neither gives a ‘one way ticket’ back to sport, but considering the lack of any evidence that surgery is better, giving physio a chance and seeing who copes along the way is definitely worth a shot.

What about the risk of developing osteoarthritis, you might ask? It turns out, there’s actually no difference between conservative and operative subgroups, so this shouldn’t count as an excuse for early surgery.

Can ACL’s actually heal?

Another reason to give conservative management a chance is the possibility of the ACL healing on its own. Until recently, it was thought that a torn ACL was torn forever. It couldn’t heal because there’s no blood supply. Recent evidence refutes this statement, showing that the ACL does have a blood supply, but a very small one.

There are also anecdotes about professional athletes who’ve had ACL ruptures that healed over time. These stories are supported by a 2021 systematic review that shows ACL tears can heal. The problem is the quality of the studies that prove this are often quite poor. In contrast, there are no high quality studies that prove ACLs cannot heal. Research is obviously still in its infancy and more high quality studies are necessary to show how to increase the odds of healing.

Unknowns and a collaborative approach

Is bracing necessary? What about weight-bearing? The only thing we can say for sure is that the ACL is less likely to heal if there’s no early protocol, highlighting the importance of starting rehab in the first week and definitely not later than three weeks.

Although there are many reasons to go for a physio first approach, it should never be forced upon someone. In the end, the patient should be able to decide what’s best for them. This requires a shared-decision making process, where the patient is informed about the pros and cons of both treatment options, knows the answers to all of his/her questions and isn’t being bombarded with difficult words and concepts. In an ideal world, these things are being discussed elaborately, but the reality is that today’s health care practitioners often only cover the basics in a quick 10 minute consult.

Wrapping up

There are still a lot of unknowns and things to improve in the management of ACL tears, but with everything we know today, we can confidently state that a conservative approach should become the gold standard, as outcomes are equal or even better than surgical management. Who really requires a reconstruction remains impossible to predict, all we know is that there is a very high psychological component and that we should try and figure out who can become a coper and who cannot. This requires time and can only be done if patients aren’t fast-tracked into surgery.

Kieran Richardson’s excellent Masterclass on Non-surgical Management of ACL Tears will provide you with a lot more insights regarding this topic, so make sure to check it out here.