ACL's... another perspective for care

            What if I told you your ACL didn’t need to be repaired?

What if I said you could return to soccer, football, basketball, lacrosse or any other cutting and pivoting sport without an ACL? Would you believe me? Believe it or not, there is mounting evidence to support this idea.  In the past, it was common to believe that an ACL injury was a season ending, maybe even career ending injury, involving surgery and an intense 9-18 month rehabilitation program. We are now realizing that this isn’t always the case. There are many instances of athletes who have returned to elite sport without ACLs – DeJuan Blair playing 4 seasons with the San Antonio Spurs of the NBA is a good example. Another such athlete returned to the English Premier League 8 weeks after a complete rupture and played several seasons without issue! John Elway, Mickie Mantle, and Joe Namath are also reported to have played their entire career (or at the very least, several seasons) without an ACL (1). Kieran Richardson, a physiotherapist in Australia asks the question: What if we treated suspected ACL tears like ankle sprains? (2) You’d likely think twice about going to the surgeon’s office if you rolled your ankle, right?

            Wait, wait, wait… A-C-what?

The ACL, or Anterior Cruciate Ligament is one of the 4 large ligaments found in your knee. It has a variety of roles, the most important believed to be limiting anterior translation and internal rotation of the tibia on the femur. More simply put, the ACL stops your lower leg from sliding forward and rotating in on your thigh bone. It is also thought to play a very important role in proprioception, or your sense of where your leg and knee is in space. When injured, people often complain of a feeling of their knee “giving way” or buckling, pain, and swelling. It is most commonly injured in 2 scenarios: contact, whereby someone or something forces the lower leg into anterior translation and internal rotation, such as someone falling into the outside of your knee with your foot planted; or in non-contact whereby the forces your own body produces or resists forces that overcome the strength of the ACL, such as trying to decelerate (or accelerate) and pivot or cut to the side, allowing the knee to fall inwards.

So you’ve injured your ACL, now what?

You’re doomed to surgery and a long road of recovery, right? Don’t be so quick to assume so... For some people, yes, this is the best course of action.  But for some people, the necessity of an ACL repair has been recently questioned. Several studies have pointed out that there are no significant differences between surgical repair and conservative management (i.e. Physiotherapy and exercise therapy) in pain, symptoms, function in sport and recreation, and early osteoarthritis development (3). Some studies actually show an increase in risk of osteoarthritis development post early surgery following ACL injury (4). Essentially, the surgery can be considered a second trauma to the knee and causes an increase in inflammatory markers that can persist for years following surgery (4).

Yeah, but what about a multi-ligament or meniscus injury to the knee?

Your body is amazing. The MCL and meniscus, also commonly injured along with the ACL, are similarly capable of recovering conservatively. 3 months minimum is recommended as a timeline for conservative management (5). Consider this: whether the injury is surgically repaired or not, you will be participating in rehab, if you want to successfully return to daily activities and sport. Also, there is a poor relationship with meniscal injuries to pain and function, meaning that just because you have pain it does not necessarily mean your meniscus is torn (even vice versa, too!) (5). One of the major problems with the desire to have an x-ray, ultrasound, MRI, or CT scan is that many partial ACL tears are indistinguishable from a complete rupture or even a normal ACL on MRI (6). In a small study, with 2 and 3 year follow ups of conservative management after ACL injury, 10 of 14 patients had shown to have complete healing of the ligament (7).

Where do I go from here?

Structured rehabilitation involving exercise with progressive strengthening, balance, and neuromuscular re-education, as well as manual therapy techniques can reduce pain, improve range of motion, and increase muscle function (8, 9). Education by the primary care provider will help in managing fear of reinjury, pain, and the psychological component of returning to sport and desired activities. So in short, given the right dose of individualized exercises, manual therapy, education and guidance, you may be able to return to pre-injury function and sporting activities.  If after structured rehabilitation you are not able to return to your desired activity, at least you can be confident that the decision for surgery was the best decision for you, for your situation.

As always, the research is mixed and the choice to have surgery completed or not is a difficult one. There are so many factors that play a significant role in this decision. Age, activity level, ability to cope, motivation, and patient preference are just some of the near endless list of influential factors. ACL surgeries are starting to be seen as an elective surgery in Scandanavian countries, similar to some other injuries like rotator cuff tears, lumbar degeneration, carpal tunnel syndrome, degenerative meniscus injuries and ankle instability surgeries. Some people truly need surgery, but there is a chance that everyone whom elects to have surgery may not need it, or may not do better after it.  This is where education about your own unique situation is incredibly important.  Talk to your surgeon, your family doctor, your care team, your coach and your family. Early ACL Repair is an option, but there are others. As an informed patient, ask yourself and your circle of care “is this surgery necessary? What do I stand to gain? What do I stand to lose?” Your body is surprisingly resilient and adaptive. Take advantage of that, but know whichever decision you make, we are here to support you in the best way we can.  

Matthias Karner, transitional Doctorate of Physcial Therapy


  1. Dr. William Sterett.
  2. Kieran Richardson.
  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 Jan 24;346:f232.
  4. Larsson S, Struglics A, Lohmander LS & Frobell R. Surgical reconstruction of ruptured anterior cruciate ligament prolongs trauma-induced increase of inflammatory cytokines in synovial fluid: an exploratory analysis in the KANON trial. Osteoarthritis Cartilage. 2017 Sep;25(9):1443-1451.
  5. Beaufils P, Pujol N. Management of traumatic meniscal tear and degerative meniscal lesions. Save the meniscus. Orthop Traumatol Surg Res. 2017 Dec;103(8S):S237-S244.
  6. Van Dyck P, De Smet E, Veryser J, Lambracht V, Gielen JL, Vanhoenacker FM, Dossche L, Parizel PM. Partial tear of the anterior cruciate ligament of the knee: injury patterns on MR imaging. Knee Surg Sports Trauamtol Arthrosc. 2012 Feb;20(2):256-61.
  7. Cost-Paz M, Ayerza MA, Tanoira I, Astoul J, Muscolo DL. Spontaneous healing in complete ACL ruptures: a clinical and MRI study. Clin Orthop Relat Res. 2012 Apr;470(4):979-985.
  8. Ofner M, Kastner A, Wallenboeck E, Pehn R, Schneider F, Groell R, Szolar D, Walach H, Litscher G, Sandner-Kiesling A. Manual khalifa therapy improves functional and morphological outcome of patients with anterior cruciate ligament rupture in the knee: a randomized controlled trial. Evid Based Complement Alternat Med. 2014 Jan 30;2014:462840.
  9. Hurd W, Axe M, Snyder-Mackler L. Management of the athlete with acute anterior cruciate ligament deficiency. Sports Health. 2009 Jan; 1(1):39-46.


Current Concept for Anterior Cruciate Ligament Reconstruction: A Criterion-Based Rehabilitation Progression


Anterior ‘not crucial’ ligament: Why we should start managing suspected ACL tears like ankle sprains (Kieran Richardson)


ACL Surgery – No Longer Kneeded? (Kieran Richardson)