English: Arthroscopic reconstruction of the anterior cruciate ligament (ACL) of the right knee. The tendon of the semitendinosus muscle was prelevated and used as an autograft. The tendon was folded to form three bundles. A string (shown here anterior to the posterior cruciate ligament) is used to pull the autograft through a channel that is drilled through the tibia and femur. The string pulls the autograft towards the upper tunnel in the top of the intercondylar area.