Which nerve block wins for shoulder surgery pain?

This study tested two types of nerve blocks to control pain after shoulder surgery. Sixty adults having arthroscopic shoulder surgery received either an interscalene block or a serratus posterior superior intercostal plane block. Researchers measured how much pain medicine patients needed in the first 24 hours, their pain levels, and side effects like diaphragm weakness. The goal was to find which block provides better pain relief with fewer breathing problems.