Efficacy of Thoracolumbar Interfascial Plane Block for Postoperative Analgesia in Lumbar Spine Surgery: A Meta-analysis of Randomized Clinical Trials

Background: Thoracolumbar interfascial plane (TLIP) block as a novel plane block technique was proposed in 2015 and can be performed in patients undergoing lumbar spine surgery. However, no meta-analysis demonstrates the effects of TLIP block on postoperative pain undergoing lumbar spine surgery. Objectives: The purpose of this study is to evaluate the postoperative analgesic efficacy of TLIP block with patient-controlled analgesia (PCA) undergoing lumbar spine surgery compared to be given PCA alone after lumbar spine surgery. Study Design: This meta-analysis pooled all data published in randomized controlled trials (RCTs) examining the efficacy of TLIP following lumbar spine surgery. Methods: We conducted a comprehensive search of PubMed, Web of Science, Embase databases, the Cochrane Library, and Google Scholar for randomized controlled trials (RCTs) up to December 2020. According to the inclusion and exclusion criteria established in advance, "TLIP" and "lumbar spine surgery" related MeSH terms and free-text words were used. All of the data on visual analog scales (VAS) scores, PCA compression frequency, PCA consumption, and nausea rates were reported. All analyses were performed with RevMan 5.4 software. Results: A total of 9 RCTs with 618 patients meet the inclusion criteria. The results demonstrated that VAS scores for pain during movement and while at rest were markedly lower in the TLIP group than those in the control group in all the postoperative periods (1-2 h, 12 h, 18 h, and 24 h) (P < 0.05). VAS scores at rest 1-2 h postoperatively (MD:-2.16; 95% CI: [-3.86,-0.46]); 12 h (MD: -1.22; 95% CI: [-2.33,-0.11]); 18 h (MD:-1.40; 95% CI: [-1.55,-1.24]); 24 h (MD:-1.38; 95% CI: [-1.94,-0.81]); VAS scores at movement 1-2 postoperatively (MD:-2.26; 95% CI: [-4.28,-0.23]); 12 h (MD:-2.11; 95% CI: [-3.13,-1.10]); 18 h (MD:-1.63; 95% CI: [-1.77,-1.48]); 24 h (MD: -1.47; 95% CI: [-1.98,-0.95]). Meanwhile, PCA compression frequency, PCA consumption, and nausea rates were significantly lower in the TLIP group after lumbar spine surgery (P < 0.05): PCA compressions frequency (MD:-4.08; 95% CI: [-5.28,-2.88]); PCA consumption (MD:-14.30; 95% CI: [-20.68,-7.92]); nausea rates (RR: 0.47; 95% CI: [0.32, 0.68]). Limitations: Despite 9 RCTs, the sample size was still small, so more high-quality RCTs with large samples will be urgently required for stronger evidence to support TLIP block in lumbar spine surgery. Conclusions: The TLIP block is an effective strategy to improve postoperative pain at rest/movement and to reduce PCA consumption in patients undergoing lumbar spine surgery, which exerts significant analgesia. In the future, it is worth being applied in lumbar spine surgery extensively.