To evaluate the efficacy of adductor canal combined with interspace between the popliteal artery and the capsule of the posterior knee (IPACK) block for multimodal analgesia after total knee arthroplasty (TKA).

Sixty American Society of Anesthesiologists physical status Ⅰ-Ⅲ patients of both sexes, aged 55-78 yr, scheduled for elective unilateral TKA under combined spinal-epidural anesthesia, were assigned into 2 groups (n=30 each) using a computer random number method: adductor canal combined with IPACK block group (group A+ I) and adductor canal block group (group A). Preventive multimodal analgesia was applied as follows: preoperative pain management education was performed; flurbiprofen 50 mg was intravenously injected before induction of anesthesia, and celecoxib 200 mg was taken orally after surgery, twice a day, to control inflammatory pain; ultrasound-guided adductor canal combined with IPACK block was performed in group A+ I, and ultrasound-guided adductor canal block was performed in group A to inhibit incisional pain; nalbuphine 0.08 mg/kg was intravenously injected to inhibit breakthrough pain. Postoperative numeric rating scale (NRS) scores at rest (NRS_r) and on movement (NRS_m) were maintained <5 within 48 h after surgery. The area under the curve(AUC) of NRS_r and NRS_m (AUC_NRSr and AUC_NRSm)were calculated within 48 h after surgery. The requirement for nalbuphine as rescue analgesic was recorded. The maximum number of ambulatory steps and maximum range of knee motion were recorded on 1 and 2 days after surgery. The development of nerve block- and postoperative rehabilitation training-related adverse events and postoperative length of hospitalization were also recorded.

Compared with group A, AUC_NRSr and AUC_NRSm were significantly decreased, the consumption of nalbuphine was reduced, and the maximum number of ambulatory steps and maximum range of knee motion were increased (P<0.05), and no significant change was found in the requirement for nalbuphine or length of hospitalization in group A+ I (P>0.05). No nerve block- and postoperative rehabilitation training-related adverse events were found in neither group.

Adductor canal combined with IPACK block can provide a relatively perfect efficacy when used for multimodal analgesia after TKA and is helpful for patient′s recovery.

Nerve block; Arthroplasty, replacement, knee; Analgesia