Interscalene Block versus Posterior Suprascapular Block for Postoperative Analgesia on Arthroscopic Shoulder Surgery: Randomized, Controlled, Prospective Study

Objectives: This study aimed to compare the effects of interscalene block and posterior suprascapular nerve block on postoperative analgesia in the first 24 hours after unilateral arthroscopic shoulder surgery.
Methods: Ninety-eight adult patients aged between 18 and 65 years, with ASA (American Society of Anesthesiologists) physical status I–II, undergoing elective arthroscopic shoulder surgery were included in this prospective, randomized controlled study. All patients were randomized into two groups: the interscalene block group (Group ISB, n=48) and the suprascapular block group (Group SSB, n=50). Both groups received 10 mL of 0.5% bupivacaine. The duration of analgesia, total opioid consumption, compli-cations, and Visual Analog Scale (VAS) scores were recorded at postoperative 0, 1, 4, 6, 12, and 24 hours.
Results: Statistical data were analyzed in 87 patients after 7 patients from Group SSNB and 4 patients from Group ISB were excluded from the study. There was no significant difference between the two groups in analgesia duration, total opioid consumption, and patient satisfaction. While VAS values at 0 hours (p<0.01), 1 hour (p<0.05), 4 hours (p<0.01), and 6 hours (p<0.01) were lower in Group ISB, the VAS value at the 12th hour was similar between Group SSB and Group ISB (p>0.05). However, the VAS value at the 24th hour was lower in Group SSB (p<0.01). The complication rate was higher in Group ISB (p<0.01).
Conclusion: It was concluded that ultrasound-guided posterior SSB for postoperative pain after arthroscopic shoulder surgery is not equivalent to ISB, especially in the early postoperative period, but it is an effective alternative technique with fewer side effects.

Keywords: Arthroscopic shoulder surgery, arthroscopy, interscalene block, postoperative pain, shoulder surgery, suprascapular block