One of the main priorities of rehabilitation after anterior cruciate ligament (ACL) reconstruction is the restoration of quadriceps strength. While there is certainly considerable pain, swelling, temporary loss of motion and reduced function associated with the surgical procedure, it has been estimated that approximately 30% of patients demonstrate quadriceps strength deficits up to 12 months after surgery, and those deficits can be as high as 30% years after the procedure. This is important, as these collective problems have been linked to reduced knee function, lower functional performance, faulty biomechanics, delayed return to sport, increased osteoarthritis risk, sub-satisfactory outcomes, and heightened risk of re-injury. (See here)
Current strength training guidelines recommend the use of higher loading mechanisms (i.e. 60-80% of 1-repetition maximum) to achieve adequate strength gains. However, training at this intensity following injury or surgery may not be feasible given symptoms of pain, swelling, loss of motion, or weight-bearing restrictions, not to mention the concern for adversely stressing healing tissues.
In recent years, the use of blood flow restriction (BFR) training has gained considerable interest. BFR training, by definition, is the combination of low-load exercises (20-40% of 1-repetition maximum) with the simultaneous application of a strap or pneumatic tourniquet/cuff to the limb(s) that occludes venous outflow while maintaining arterial inflow. This method is believed to induce muscle hypertrophy (mass and strength gains) through a series of physiologic events that leads to tissue hypoxia, cellular swelling, elevated systemic growth hormone production, among other metabolic processes.
In a recent systematic review (see here), the authors found that low-load blood flow restriction training (LL-BFR) after ACL reconstruction may be beneficial on both quadriceps strength and mass compared to non-BFR training. In addition, they found that LL-BFR may be an effective alternative to non-BFR as it relates to knee joint pain and ACL laxity.
For a more advanced explanation of BFR principles, safety, and recommendations refer to this article.
At Uncommon Physical Therapy, we offer BFR training as part of a comprehensive rehabilitation program following ACL reconstruction.
Schedule with us today to learn more.
