What you need to know about ACL Injuries

March 22, 2022 | Physiotherapy, Sports

The knee is often known as the most complex joint in the human body and is subject to large forces during sporting activities. These forces are resisted by a number of structures including the five main ‘static’ restraints of the knee: the two cruciate ligaments, the two collateral ligaments, and the popliteus tendon. The anterior cruciate ligament (ACL) is arguably the most important and most well-known of these five structures; if the ACL was in the band N-Sync, for example, it would be Justin Timberlake!

Although a direct blow to the knee can injure the ACL, you may not know that almost 80% of injuries are caused by non-contact events involving a sudden deceleration or change in direction. In females, the rupture of the ACL is 2.5 times more likely than in males. The most common reasons for these gender differences are:

  • Reduced knee and hip bending during landing
  • Increased “knock-knee’d-ness” (greater genu valgum of the knee)
  • Increased internal rotation of the thigh bone,
  • High quadriceps activity unbalanced by the hamstrings 
  • The influence of the menstrual cycle 

How do you know if you have torn your ACL?

The consistent description of ACL injuries includes twisting of the knee, feeling or hearing a pop, unable to continue the activity or even bear weight, or hemarthrosis as the knee fills up with blood very quickly because the ACL has an abundant blood supply. As the pain settles, walking and running in a straight line is not usually a problem, but when attempting to turn or sidestep, the knee feels wobbly and the individual may demonstrate instability by sliding their clenched fists against each other.

What to do if you have torn your ACL?

After an ACL injury, deficits occur in strength, proprioception, muscle timing, and gait patterns. In fact, strength and proprioception deficits can occur in an injured and non-injured limb. There are two approaches that can be taken post ACL injury – Operative and Conservative. The operative approach involves ACL reconstruction surgery vs the conservative approach of physiotherapy treatment. 

ACL reconstruction surgery is indicated in ACL deficient patients with symptomatic instability or a desire to compete in high-risk activities. Research demonstrates that physiotherapy provided pre-operatively is effective in increasing strength and balance. This may limit the number of episodes of ‘giving way’ and decrease the incidence of re-injury in the ACL deficient knee. However, studies have shown that patients who did not undergo surgery and focused on the rehabilitation of the knee did not have any instability in the knee with treatment.  Therefore, these conservatively treated patients were not exposed to surgery and its associated risks. 

If an ACL injury is confirmed, it is important to consider whether it is actually symptomatic (giving way) before rushing to surgery. ACL reconstructions aim to stabilize an unstable knee, but if it’s not unstable in the first place, what purpose does it serve?

With treatment, a gradual return to sport is initiated at the six to nine-month mark. This can begin only if the individual’s knee does not present with pain or effusion during or after functional sport-specific training drills. The individual must also be able to demonstrate the appropriate strength and endurance needed for their specific sport.

How do I prevent an ACL Injury?

ACL injury rates appear to be on the increase. This is a concern as recent reports show that rates of ACL injury have grown most rapidly at the younger end of the age spectrum. 

Implementing an ACL injury prevention program can be extremely beneficial for all individuals. Keep in mind that this program will not eliminate ACL tears from occurring but can help decrease the risk. There are five key steps that should be included in the planning of this program: 

  • Identification
  • Exercises
  • Training load and volume
  • Training Frequency
  • Exercise timing

As a helping hand, a physiotherapist is someone who routinely rehabs individuals following an ACL injury, and is capable of observing your movements, screening you for deficits, and helping you to correct them. 

To learn more, talk to your physiotherapist or schedule an appointment at www.curavita.com.  You can also call our CURAVITA Byward Clinic at 613-237-9000 or our CURAVITA Glebe Clinic at 613-860-8600.