Implementation and evaluation of a multimodal analgesia protocol for total knee arthroplasty including ultrasound-guided adductor canal block and periarticular local anesthetic infiltration

Abstract

Background: Ultrasound-guided regional anesthesia is a safe and effective technique in postoperative pain management. This study evaluates the implementation an analgesic protocol for total knee arthroplasty (TKA) including different nerve blocks. Methods: An observational ambispective non randomized cohort study was performed between a group of patients undergoing TKA who received local infiltration analgesia plus adductor canal block (LIA+ACB) as part of a new analgesic protocol against a previous group who received perineural femoral catheter plus sciatic nerve block (PFC+SNB). The measurement of pain intensity was made using the numerical rating scale (NRS). The main outcome was the immediate postoperative pain, at 24 and 48 hours. The fulfillment of physical rehabilitation goals was evaluated as a secondary outcome. Results: 112 patients were analyzed (67 in LIA+ACB and 45 in PFC+SNB). Both groups were comparable in demographic characteristics. The median pain at rest on the first and second postoperative days was NRS 2/10 for both groups. The average pain on movement on the second postoperative day was NRS 5/10 for patients with LIA+ACB and 4/10 for patients with PFC+SNB, p=0,073. The percentage of patients who fulfilled ≥80% of the rehabilitation goals was similar in both groups (p=0,201). Conclusions: In the TKA postoperative analgesic management, both techniques are equivalent during the first 48 hours. Although it is known that the LIA+ACB technique generates less motor impairment of the quadriceps muscle, this was not reflected on better performance during physical rehabilitation, possibly due to insufficient analgesic control at 48 hours.