Struggling to lift your leg after knee surgery? You are not alone. In this post, Dr. Justin Lin explains why your quadriceps shut off after ACL repair or knee replacement due to Arthrogenic Muscle Inhibition (AMI). Discover why the straight leg raise after knee surgery is the ultimate reactivation switch for your brain and leg, how quad strength predicts walking independence, and a step-by-step PT protocol to perform this crucial exercise safely at home.