Background and Aims Appropriate pain management is essential to improve the postoperative recovery after total hip arthroplasty (THA). Some randomized trials have indicated that anterior quadratus lumborum block (QLB) provides effective postoperative analgesia in THA. However, whether anterior QLB improves postoperative recovery after THA is unclear.

Methods The participants were randomly assigned to either the anterior QLB or placebo groups. After induction of general anesthesia, anterior QLB was performed by using 0.25% levobupivacaine or normal saline. The primary outcome was the quality of recovery 40 score (QoR-40). Secondary outcomes included the visual analog scale score of pain intensity at rest and movement, intraoperative and postoperative doses of fentanyl, and incidence of postoperative nausea and vomiting.

Results This study included and analyzed 70 participants of the anterior QLB group and 69 participants of the placebo group. The pain dimension in QoR-40 score 24 hours after the surgery was higher in the anterior QLB group than in the placebo group (median 30.5 [IQR 27.0, 32.0] vs 28.0 [24.0, 32.0] p=0.033). However, total score of QoR-40, which is the primary outcome, were not statistically significant different between each group (169 [153, 177] vs 158 [142, 177] p=0.122) (table 1). The anterior QLB group needed less intraoperative dose of fentanyl than the placebo group (275 [200, 350] vs 350 [250, 425] p=0.007). Other secondary outcomes were not statistically significant different.

Conclusions Anterior QLB combined with general anesthesia did not improved postoperative recovery after total hip arthroplasty.