Triple-injection perisartorius block versus dual subsartorial block for total knee arthroplasty: a double-blinded randomized controlled study

Background: Optimal pain control is essential for early rehabilitation after total knee arthroplasty (TKA). Blockade of the anterior femoral cutaneous nerves which is included in the triple-injection perisartorius (TIPS) block, may provide superior postoperative analgesia compared with the dual subsartorial block (DSB). The primary aim was to determine whether the addition of a suprasartorial injection as part of the TIPS block results in better visual analogue scale (VAS) scores than DSB during the first 24 postoperative h. Methods: Eighty-eight patients scheduled for TKA were randomly assigned to two groups after induction of general anesthesia. Group DSB received a femoral triangle block and a distal adductor canal block, whereas Group TIPS received DSB plus a third injection superficial to the sartorius muscle within the duplicated layer of the fascia lata.Results: Demographic characteristics were comparable between the two groups. The resting VAS scores at 4, 8, and 12 h postoperatively were significantly lower in the TIPS group (median: 2, 2, and 1, respectively) than in the DSB group (median: 4, 3, and 2, respectively) (P < 0.001, 0.001, and 0.001, respectively). Similarly, the dynamic VAS scores at 4, 8, and 12 h were significantly lower in the TIPS group (median: 3, 3, and 2, respectively) than in the DSB group (median: 4, 4, and 2, respectively) (P < 0.001, 0.001, and 0.005, respectively). Morphine consumption and time to first analgesic requirement were significantly lower in the TIPS group (P < 0.001). Functional assessments using the Timed Up and Go Test and the 30-s Chair Stand Test showed no significant differences between groups.Conclusions: The TIPS block provides superior postoperative analgesia after TKA compared with DSB, as evidenced by lower VAS scores and reduced opioid requirements in the early postoperative period. The addition of a suprasartorial injection to DSB offers optimal motor-sparing analgesia without compromising functional recovery.