Do I need surgery following ACL tear?

Anterior cruciate ligament (ACL) tear is a common and serious knee injury in the active population. ACL injuries can lead to unsatisfactory knee function, decreased activity, and poor knee related quality of life. In addition, many patients with a torn ACL will develop osteoarthritis of the knee1. Considering the potential impacts on physical health and quality of life it is important to make an informed decision on the management of ACL rehabilitation.

The common belief amongst the general public (and many health professionals), is that surgery is the only rehabilitation option following an ACL tear. This is likely due to the influence of well documented and publicized surgical rehabs of professional athletes. However, what most people are unaware of is that non-surgical management of ACL tears is a viable option and at the very least should be considered for a large portion of people that have suffered an ACL tear.

In 2010 a high quality randomized control study called the KANON study2 was published out of Sweden. It was the first high quality study that compared the outcomes of surgical and non-surgical management of acute ACL tears at two and five year follow-up. The subjects in this study had an average age of 26 and were physically active in sport. The subjects had suffered an acute ACL tear and were assigned into two groups. The first group performed rehab in addition to early surgical intervention (within 10 weeks of injury), the second group performed similar rehab in addition to the option of delayed ACL reconstruction if required. The average number of rehab visits was 53 for the surgical group and 63 for the delayed option group. In total 61 subjects had early reconstruction and 59 performed the extended rehab. Of the 59 in the extended rehab group, 30 went on to have a delayed ACL reconstruction (average timeline of 11.6 months post injury). This is significant as the delayed rehab group resulted in 49% of its subjects not requiring ACL surgery.

The primary goal of this study was not only to identify how many subjects may not require ACL reconstruction but also to compare key outcome measures at 2 and 5 years post injury between the two groups. What the study found is that there was no statistically significant difference in pain, symptoms, function in activities of daily living, function in sports and recreation, knee related quality of life, general physical or mental health status, return to pre-injury activity level, radiographic osteoarthritis, or meniscus surgery between the group assigned to early ACL reconstruction and those assigned to initial rehab with the option of delayed reconstruction2,3.

All of this is to say that rehabilitation in addition to the option of delayed ACL reconstruction resulted in 49% of subjects not requiring surgery and having no statistical difference in key objective measures at 2 and 5 years post injury compared to the subjects that did have early reconstruction. Therefore, if all of the study participants had gone through a conservative management plan could an additional 30 ACL reconstructions have been avoided with no adverse effect on outcomes?

The impacts of this study are significant on the rehabilitation world as it provided us our first high quality study to support the decision of a non-surgical option in the management of an acute ACL tear.

It is important to note that this study did have some key exclusion criteria including the presence of a full thickness MCL or LCL tear and full thickness cartilage lesion on MRI. Therefore, imaging and discussing imaging results with an orthopedic surgeon is an essential component of determining the most appropriate management option.

In conclusion, ACL injuries are a common and significant knee injury that can lead to unsatisfactory knee health, decreased activity levels and a higher risk of future knee OA. The KANON study was the first high quality randomized controlled trial that provided evidence to support a strategy of rehabilitation plus optional delayed reconstruction of ACL injuries. With this strategy, nearly half of ACL reconstructions could be avoided without adversely affecting outcomes.

If you have had an ACL injury it is important to know that you may have rehabilitation options. It is important to have a team around you that is familiar with the management and outcomes of ACL rehab. This includes a physiotherapist, sports medicine doctor and orthopedic surgeon. With the right team, you can be confident that you are making the most informed and best decision for your physical health and quality of life.

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1 – High prevalence of osteoarthritis 14 years after an anterior cruciate ligament tear in male soccer players: a study of radiographic and patient relevant outcomes. Ann Rheum Dis 2004;63:269-73.

2 – Frobell, RB, Roos, EM, Roos, HP, Ranstam, J, Lohmander, LS. A randomized trial of treatment for acute anterior cruciate ligament tears. N Engl J Med. 2010;363(4):331-342.

3 – Frobell, RB, Roos, HP, Roos, EM, Roemer, FW, Ranstam, J, Lohmander, LS. Treatment for acute anterior cruciate ligament tear: five year outcome of randomised trial. BMJ. 2013;346:F232.