Group three (G3): proximal ACB technique
After the US identification of the proximal end of the AC, the transducer was moved distally to identify the adductor hiatus, where the femoral artery diverges from the sartorius muscle and goes through the adductor magnus tendon. Once the two ends of the AC were located, the distance between them was divided in thirds. The injection point was located where the proximal and medium thirds met. The needle was inserted from the lateral aspect of the thigh until locating the tip laterally to the femoral artery.