Joint replacement surgeries rank among the most common procedures performed globally, yet the optimal anesthetic approach remains surprisingly unclear. While surgeons and anesthesiologists have long debated whether spinal or general anesthesia delivers better outcomes, conflicting evidence has prevented clear clinical guidelines from emerging. This ambiguity affects millions of patients annually who undergo hip and knee arthroplasties. Danish researchers are launching a comprehensive systematic review to definitively compare serious adverse events between spinal and general anesthesia for joint replacement procedures. Their protocol follows rigorous PRISMA guidelines and will analyze randomized controlled trials across major medical databases. The primary focus centers on serious adverse events, while secondary measures include pain levels, opioid requirements, mobilization timing, and hospital stays. The methodology incorporates Trial Sequential Analysis, a statistical approach that helps determine when sufficient evidence exists to draw reliable conclusions. Previous systematic reviews yielded contradictory findings, partly due to methodological limitations and the inclusion of lower-quality studies. This updated analysis specifically targets randomized trials comparing the two anesthetic approaches head-to-head in adult joint replacement patients. The timing proves crucial as healthcare systems worldwide grapple with optimizing surgical outcomes while managing costs. Joint replacements continue growing as populations age, making anesthetic choice increasingly consequential for patient safety and resource allocation. If this review identifies a clear winner between spinal and general anesthesia, it could standardize practice patterns and potentially improve outcomes for the estimated 2 million joint replacements performed annually worldwide.