Efficacy of Ultrasound-Guided Quadratus Lumborum Block for Postoperative Analgesia After Hip Arthroplasty: A Meta-Analysis of Randomized Controlled Trials

Abstract

BackgroundUltrasound-guided quadratus lumborum (QL) block as a novel regional anesthetic technique was proposed in 2007 that can be applied in patients following hip arthroplasty. This study aimed to evaluate the efficacy of the QL block for pain control in patients undergoing hip arthroplasty. MethodsWe performed a comprehensive search of PubMed, Web of Science, Scopus, Cochrane Library, Embase databases, Google Scholar, and CNKI for randomized controlled trials up to December 2021. According to the inclusion and exclusion criteria established in advance, “QL block” and “hip arthroplasty” related MeSH terms and free-text words were used. ResultsOur meta-analysis included 11 randomized controlled trials involving a total of 830 patients between 2018 and 2021. The results indicated that compared to the non-QL block group, Visual Analog Scale (VAS) score at mobilization in the QL block group demonstrated statistical and clinical significance at all time points (12, 24, and 48 hours), but VAS score at rest failed to reach the MCID (minimal clinically important difference). Meanwhile, opioid consumption in the QL block group only demonstrated statistical and clinical significance at 48 hours postoperatively, but did not reach the MCID at 12 or 24 hours postoperatively. The QL block increased satisfaction scores. There was a statistically significant reduction in the incidence of postoperative nausea and vomiting, but no difference in the incidence of pruritus and urinary retention. ConclusionThe QL block significantly reduced postoperative VAS score at mobilization, and opioid consumption at 48 hours in patients after hip arthroplasty compared to no block, which reached the MCID. The QL block also decreased postoperative nausea and vomiting and increased satisfaction scores. Although these are promising results, the clinical relevance of the efficacy of the QL block remains to be further understood as larger studies are needed.