Fig. 2. Changes in numeric rating scale perioperative pain severity. NRS: numeric rating scale, CACB: continuous adductor canal block, IVACB: intravenous patient-controlled analgesia with adductor canal block, Pre: before ACB, Post: 30 minutes after ACB, 30 min: 30 minutes after surgery, 2 h: 2 hours after surgery, 4 h: 4 hours after surgery, 8 h: 8 hours after surgery, 24 h: 24 hours after surgery, 48 h: 48 hours after surgery. *P < 0.05 compared with Group IVACB.
