Diaphragm-Sparing Nerve Blocks for Arthroscopic Rotator Cuff Repair: A Systematic Review of Efficacy, Safety, and Multimodal Analgesia Integration

Background: Arthroscopic rotator cuff repair (ARCR) is associated with significant postoperative pain. While the interscalene brachial plexus block (ISB) is the analgesic gold standard, it causes nearly universal hemidiaphragmatic paralysis. This systematic review evaluated the efficacy, safety, and opioid-sparing effects of diaphragm-sparing nerve blocks (DSNBs) as alternatives to ISB. Methods: A systematic literature search was conducted following PRISMA guidelines in PubMed, Scopus, and the Cochrane Library for studies published between January 1, 2010, and May 1, 2025. After screening 193 identified records, 36 studies met the inclusion criteria and were analyzed. Results: Diaphragm-sparing nerve blocks—including the Superior Trunk Block (STB), Suprascapular plus Axillary Nerve Block (SSNB + AXNB), and Costoclavicular Block (CCB)—provided analgesic efficacy equivalent to ISB. The key finding was a dramatic reduction in the incidence of hemidiaphragmatic paralysis, from nearly 100% with ISB to below 10% with DSNBs. Specifically, the STB achieved non-inferior analgesia with only 0–5% diaphragmatic involvement. When incorporated into multimodal analgesia protocols, these techniques reduced postoperative opioid consumption by approximately 40–60% and demonstrated significant safety advantages for patients with pulmonary comorbidities, without compromising pain control or block success rate. Conclusions: Diaphragm-sparing nerve blocks represent effective and safe alternatives to ISB for pain management after ARCR, establishing a new standard of care that prioritizes respiratory safety. They achieve comparable analgesia while markedly reducing the risk of hemidiaphragmatic paralysis. Block selection should be individualized based on patient factors and surgical needs, but evidence strongly supports the integration of DSNBs into clinical practice to enhance recovery and minimize opioid-related side effects.