Subomohyoid Anterior Suprascapular Block versus Interscalene Block for Arthroscopic Shoulder Surgery

Abstract

Background: Interscalene brachial plexus block, the pain relief standard for shoulder surgery, is an invasive technique associated with important complications. The subomohyoid anterior suprascapular block is a potential alternative, but evidence of its comparative analgesic effect is sparse. The authors tested the hypothesis that anterior suprascapular block is noninferior to interscalene block for improving pain control after shoulder surgery. As a secondary objective, the authors evaluated the success of superior trunk (C5-C6 dermatomes) block with suprascapular block. Methods:In this multicenter double-blind noninferiority randomized trial, 140 patients undergoing shoulder surgery were randomized to either interscalene or anterior suprascapular block with 15 ml of ropivacaine 0.5% and epinephrine. The primary outcome was area under the curve of postoperative visual analog scale pain scores during the first 24 h postoperatively. The 90% CI for the difference (interscalene-suprascapular) was compared against a -4.4-U noninferiority margin. Secondary outcomes included presence of superior trunk blockade, pain scores at individual time points, opioid consumption, time to first analgesic request, opioid-related side-effects, and quality of recovery.Results: A total of 136 patients were included in the analysis. The mean difference (90% CI) in area under the curve of pain scores for the (interscalene-suprascapular) comparison was -0.3 U (-0.8 to 0.12), exceeding the noninferiority margin of -4.4 U and demonstrating noninferiority of suprascapular block. The risk ratio (95% CI) of combined superior trunk (C5-C6 dermatomes) blockade was 0.98 (0.92 to 1.01), excluding any meaningful difference in superior trunk block success rates between the two groups. When differences in other analgesic outcomes existed, they were not clinically important.conclusions: The suprascapular block was noninferior to interscalene block with respect to improvement of postoperative pain control, and also for blockade of the superior trunk. These findings suggest that the suprascapular block consistently blocks the superior trunk and qualify it as an effective interscalene block alternative. What We Already Know about This Topic• Interscalene brachial plexus block is a commonly used procedure for shoulder surgery, but it can be associated with important complications What This Article Tells Us That Is New• Subomohyoid anterior suprascapular block is noninferior to interscalene block in providing analgesia for the first 24 h after shoulder surgery • Subomohyoid anterior suprascapular block does not appear to differ significantly from interscalene block in terms of superior trunk blockade or overall quality of recovery T he ongoing quest for effective alternatives to the interscalene block of the brachial plexus for postoperative analgesia after shoulder surgery 1 has been prompted by the interscalene block's invasiveness 2,3 and undesirable respiratory side effects related to phrenic nerve block, 4 which restrict its use in certain population...

Randomized, controlled trial comparing respiratory and analgesic effects of interscalene, anterior suprascapular, and posterior suprascapular nerve blocks for arthroscopic shoulder surgery

“…Our results are congruent with those of Auyong's recent study [21] comparing single-shot anterior SSB, supraclavicular, and interscalene blocks, which showed that anterior SSB provided non-inferior analgesia than interscalene and also preserved vital capacity. Similarly, Abdallah et al [22] also found that the anterior SSB was not inferior to the ISB for postoperative pain control. However, the analgesic effects of posterior SSB are inferior to those of ISB, with high pain scores at 6 and 12 hours on movement.…”

Suprascapular nerve block is a clinically attractive alternative to interscalene nerve block during arthroscopic shoulder surgery: a meta-analysis of randomized controlled trials

“…Because some articles did not compare the suprascapular nerve block with interscalene nerve block, five studies were excluded. Finally, we identified 1255 patients assessed in 17 randomized controlled trials [ 1 , 3 , 7 , 11 , 20 , 21 , 25 , 28 – 31 , 34 , 35 , 40 , 42 – 44 ] (Fig. 1 ).…”

Continuous suprascapular nerve block compared with single-shot interscalene brachial plexus block for pain control after arthroscopic rotator cuff repair

“…Many studies have confirmed the efficacy of these two methods compared to control, intravenous patient-controlled analgesia (IV-PCA), and local anesthetic infiltration ( 5-7 , 11 , 16 ,). Although many studies have compared the analgesic efficacy of SSNB and ISNB ( 2 , 17 , 21 , 27 - 39 ), this is the first study to compare C-SSNB and S-ISNB with rebound pain at 6-12 h after surgery as a primary endpoint.…”