Regional anesthesia strategies for proximal humerus fracture surgery: anatomical considerations, diaphragm-sparing techniques, and expert perspectives—a narrative review

BACKGROUND: Proximal Humerus Fractures (PHFs) are increasingly common, particularly in elderly patients with osteoporotic bone. Surgical and anesthetic management significantly influence outcomes, yet evidence guiding optimal strategies remains limited. Regional Anesthesia (RA) offers effective analgesia, opioid sparing, and the potential to avoid general anesthesia in frail or high-risk patients. This narrative review summarizes current knowledge, highlights diaphragm-sparing approaches, and integrates expert clinical insights to provide practical recommendations for anesthesiologists managing PHF surgery. METHODS: A narrative review was conducted using a structured non-systematic search of PubMed, Embase, and Scopus (January 2000–November 2025). Eligible studies included adults undergoing PHFs surgery with RA and reporting clinical outcomes; case reports, purely anatomical studies, non-surgical analgesia, and non-PHF procedures were excluded. Nine studies met inclusion criteria. Additional references provided anatomical, surgical, and anesthetic context. Orthopedic data were reviewed to contextualize anesthetic strategies, and an “Expert Opinion” section integrated multidisciplinary insights. RESULTS: Among the nine PHF-specific studies, evidence was limited and heterogeneous, focusing mainly on analgesic efficacy, technical feasibility, and respiratory safety rather than long-term outcomes. Interscalene Brachial Plexus Block (ISBPB) provided effective analgesia but was frequently associated with phrenic nerve involvement. Diaphragm-sparing approaches—such as Superior Trunk Block (STB), infraclavicular techniques, and selective suprascapular and axillary nerve blocks—may reduce respiratory impairment while maintaining acceptable analgesia. Only a minority of studies evaluated continuous RA, reporting prolonged postoperative pain control and opioid sparing in small cohorts. Additional literature supported tailoring block selection to fracture pattern, surgical approach, and patient comorbidities. Expert perspectives emphasized pragmatic, patient-centered strategies, particularly for high-risk or frail patients. CONCLUSIONS: RA is an important component of PHFs surgery, although PHF-specific evidence remains limited. Integrating available data, contextual literature, and expert experience supports an individualized approach balancing analgesic efficacy with safety. Diaphragm-sparing and selected continuous techniques may be considered in patients at increased respiratory risk. Further well-designed studies are needed to refine patient selection and evaluate functional and long-term outcomes.