Background and Aims The anterior suprascapular block (ASSB) is a recently described regional anaesthesia technique for non-arthroplasty shoulder surgery. This systematic review and meta-analysis compared the early analgesic efficacy of the ASSB to the interscalene nerve block(ISB) in patients presenting for non-arthroplasty shoulder surgery.

Methods After performing a systematic review, randomised control trials comparing ISB and ASSB performed for ambulatory or arthroscopic surgery were included for analysis. Only randomised controlled trials of arthroscopic shoulder surgery comparing ASSB versus ISB were included. Analgesia consumption intraoperatively and in PACU were assessed. Meta-analysis was performed using a random effects model. The GRADEpro tool was used to determine certainty outcome results.

Results A total of six studies were eligible for evaluation in this systematic review and meta-analysis. All six studies examined the effect on opioid consumption, demonstrating no statistically significant differences between studies. Four studies measured intraoperative opioid use with heterogenous, non-significantly different results (MD=0.26 mg; 95%I=-0.86 to 1.38 mg; I2=77%; p=0.65; moderate certainty). Similarly, with heterogeneity there was no difference in opioid requirements in PACU (MD=0.74; 95%CI=-0.18 to 1.66 mg; I2=60%; p=0.11; moderate certainty).

Conclusions The analgesia requirements when using anterior suprascapular block in ambulatory or arthroscopic shoulder surgery showed no significant difference to interscalene block for opioid use intraoperatively and in PACU.