ACL Injury: Early Surgery, Delayed Surgery, or Exercise Therapy?

Jun 07, 2017

In a recent study in the British Journal of Sports Medicine, the researchers found that delaying ACL surgery and treating with exercise therapy alone may provide better outcomes in the long term inactive individuals.

The anterior cruciate ligament (ACL) is one of the most commonly injured ligaments of the knee. Injuries to the ACL usually occur from twisting the knee while the foot is firmly on the ground or when landing from a jump. Serious injuries can affect sporting careers including football, basketball, netball, and alpine skiing.

Surgical reconstruction is a very common method to repair a torn ACL. However, not all cases come out with better results, and the long-term outcomes may come out differently depending on how the injury has been treated.

Why Some Post Surgical Outcomes Can Be Poor

There are factors that have been associated with worse results such as meniscal injury, related meniscal surgery and full-thickness cartilage damage during ACL reconstruction. These worse results are referred to as pain, symptoms, function, activity levels, and quality of life.

Psychological factors play a role as well including external locus of control, fear of re-injury and reduced self-efficacy of the knee. Other factors that can lead to worse outcomes are smoking and low education levels.

The Study

Filbay et al conducted a study involving 118 active adults with ACL rupture. The data gathered in the exploratory analysis of the Knee Anterior Cruciate Ligament, Nonsurgical versus Surgical Treatment (KANON) trial was used.

The aims of the study were to identify injury-related, patient-reported and treatment-reported predictive factors for 5-year patient-reported results in individuals with ACL rupture, and to compare predictive factors between the three as-treated groups – early reconstruction with exercise therapy, exercise therapy with delayed reconstruction and exercise therapy alone.

After the randomisation, the surgeries were performed 46 weeks later, while the delayed surgeries ranged from 2-56 months later. All groups performed the same neuromuscular exercise programme supervised by physiotherapists.

The researchers found that experiencing an ACL graft rupture or contralateral ACL rupture, and having at least one knee surgery not involving ACL reconstruction or revision were associated with worse outcomes in individuals with an ACL tear.

It was also found that participants who were managed with exercise therapy alone reported an estimated 10-point better Knee injury and Osteoarthritis Outcome Score (KOOS) at 5 years, as compared to participants who underwent early reconstruction with exercise therapy. Additionally, delaying ACL reconstruction and managing ACL rupture with exercise therapy alone are associated with better outcomes.

Individuals with severe knee symptoms following ACL rupture may benefit from commencing exercise therapy before considering ACL surgery.

How These Findings May Impact the Clinical Practice in the Future

If the findings would be supported by further study, the characteristics including associated meniscus damage and a higher degree of self-reported knee injury within 4 weeks of ACL rupture, may be used to indicate the likelihood of benefiting from exercise therapy first before considering surgery.

Also, an individual with an acute ACL rupture can be able to make an informed decision about treatment options, and clinicians should be able to personally discuss the possibility of better or worse outcomes with each treatment option. They should explain the benefits and risks associated with different treatment methods.

If you need exercise therapy for your ACL injury in Perth, book in today with the experts at Happy Physio.



  • Filbay SR, Roos EM, Frobell RB, et al. Delaying ACL reconstruction and treating with exercise therapy alone may alter prognostic factors for 5-year outcome: an exploratory analysis of the KANON trial. Br J Sports Med Published Online First: 17 May 2017. doi: 10.1136/bjsports-2016-097124