Impact of local infiltration analgesia on the quality of recovery after anterior total hip arthroplasty: a randomised, triple-blind, placebo-controlled trial

Background: Local infiltration analgesia (LIA) is commonly used in anterior total hip arthroplasty (THA) surgery; however, evidence for its efficacy is lacking. We hypothesized that LIA with 0.2% ropivacaine when compared with injection of placebo (0.9% saline) would improve patient quality of recovery on postoperative day (POD) 1, as measured by the Quality of Recovery-15 (QoR-15) score. Methods: Patients scheduled to have a primary unilateral anterior THA with a single surgeon in a tertiary level metropolitan hospital were randomized to receive LIA with either 2.5 mL/kg of 0.2% ropivacaine or 0.9% saline as placebo. Patients and clinical and study personnel were blinded to group allocation. Perioperative care was standardized and this included spinal anesthesia and oral multimodal analgesia. The primary outcome was a multidimensional (pain, physical comfort, physical independence, emotions, and psychological support) patient-reported quality of recovery scale, QoR-15, measured on POD 1. Results: One hundred sixty patients were randomized; 6 patients were withdrawn after randomization and 2 patients had incomplete outcome data. The intention-to-treat analysis included 152 patients. The median (interquartile range [IQR]) QoR-15 score on POD 1 of the ropivacaine group was 119.5 (102-124), compared with the placebo group which had a median (IQR) of 115 (98-126). The median difference of 2 (95% confidence interval [CI], -4 to 7; P = .56) was not statistically or clinically significant. An as-per-protocol sensitivity analysis of 146 patients who received spinal anesthesia without general anesthesia, and the allocated intervention, also showed no evidence of a significant difference between groups. Secondary outcomes (worst pain numerical rating scale at rest and with movement on POD 1, opioid consumption on PODs 1 and 2, mobilization on POD 1, Brief Pain Inventory severity and interference on POD 90, and length of stay) were similar in both groups. Conclusions: LIA with