Anterior Quadratus Lumborum Block Does Not Provide Superior Pain Control after Hip Arthroscopy: A Double-blinded Randomized Controlled Trial

Abstract

Background Hip arthroscopy is associated with moderate to severe postoperative pain. This prospective, randomized, double-blinded study investigates the clinically analgesic effect of anterior quadratus lumborum block with multimodal analgesia compared to multimodal analgesia alone. The authors hypothesized that an anterior quadratus lumborum block with multimodal analgesia would be superior for pain control. Methods Ninety-six adult patients undergoing ambulatory hip arthroscopy were enrolled. Patients were randomized to either a single-shot anterior quadratus lumborum block (30 ml bupivacaine 0.5% with 2 mg preservative-free dexamethasone) or no block. All patients received neuraxial anesthesia, IV sedation, and multimodal analgesia (IV acetaminophen and ketorolac). The primary outcome was numerical rating scale pain scores at rest and movement at 30 min and 1, 2, 3, and 24 h. Results Ninety-six patients were enrolled and included in the analysis. Anterior quadratus lumborum block with multimodal analgesia (overall treatment effect, marginal mean [standard error]: 4.4 [0.3]) was not superior to multimodal analgesia alone (overall treatment effect, marginal mean [standard error]: 3.7 [0.3]) in pain scores over the study period (treatment differences between no block and anterior quadratus lumborum block, 0.7 [95% CI, –0.1 to 1.5]; P = 0.059). Postanesthesia care unit antiemetic use, patient satisfaction, and opioid consumption for 0 to 24 h were not significantly different. There was no difference in quadriceps strength on the operative side between groups (differences in means, 1.9 [95% CI, –1.5 to 5.3]; P = 0.268). Conclusions Anterior quadratus lumborum block may not add to the benefits provided by multimodal analgesia alone after hip arthroscopy. Anterior quadratus lumborum block did not cause a motor deficit. The lack of treatment effect in this study demonstrates a surgical procedure without benefit from this novel block. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Efficacy of Quadratus Lumborum Block for Pain Control in Patients Undergoing Hip Surgeries: A Systematic Review and Meta-Analysis

“…While most of the studies included in our review utilized the posterior QLB, a few did report the use of anterior or lateral QLB but with variable results. While Haskins et al (33) reported the lack of beneficial effect with anterior QLB in hip arthroscopic surgeries, Kukreja et al (26) found a statistically significant reduction in pain scores and opioid consumption with anterior QLB in patients undergoing hip arthroplasties. Another retrospective study of Kinjo et al (27) also reported no significant difference in pain scores with anterior QLB.…”

“…Eighteen articles were selected for full-text analysis. Of them, thirteen studies fulfilled the inclusion criteria and were analyzed in this review (21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33).…”

“…Details of the included studies are presented in Table 1. Nine (21,24,26,(28)(29)(30)(31)(32)(33) were RCTs while four (22,23,25,27) were retrospective studies. Most studies were carried out in the USA or China.…”

“…Most studies were carried out in the USA or China. Seven (21,22,25,26,28,30,31) were conducted on patients undergoing hip arthroplasty, while five (23,27,29,32,33) were on patients undergoing arthroscopic surgeries. The sample size of the QLB group ranged from 10 to 79 patients while that of the control group ranged from 10 to 159 patients.…”

“…Subgroup analysis of RCTs (MD: −6.59, 95% CI: −10.66, −2.52 I 2 = 98% p = 0.002) and the lone non-RCT (MD: −23.75, 95% CI: −36.02, −11.48 p = 0.0001) demonstrated similar results (Figure 4). On excluding two studies on arthroscopy (29,33), meta-analysis of RCTs reporting only arthroplasty results revealed significantly reduced opioid consumption in the QLB group (MD: −8.67, 95% CI: −14.90, −2.44 I 2 = 98% p = 0.006) (Supplementary Figure 2).…”