Background/Objectives: Rates of degenerative spinal pathology are increasing, driving interest in minimally invasive surgical (MIS) techniques that facilitate faster recovery. Full endoscopic lumbar discectomy (FELD) and biportal endoscopic lumbar discectomy (BELD) offer reduced tissue disruption, but comparative outcomes versus non-endoscopic MIS and optimal patient selection remain unclear. This systematic review examines pre-operative characteristics and post-operative outcomes of endoscopic lumbar microdiscectomy (ELMD) compared to MIS and open techniques. Methods: A PRISMA-guided search of PubMed, Embase, Scopus, and hand searches through 31 September 2024 identified studies on lumbar spinal surgery using endoscopic techniques, restricted to level 1a/b and 2a evidence. Articles were subgrouped by surgery type, with this analysis focusing on ELMD. Data extraction included risk-of-bias assessment, and meta-analysis was performed using multivariate mixed-effects regression. Pre-operative patient characteristics and post-operative outcomes for endoscopic lumbar microdiscectomy (ELMD) were directly compared to both open microdiscectomy and minimally invasive non-endoscopic microdiscectomy (MIS) techniques. Within the ELMD cohort, we further analyzed differences between full endoscopic (FELD) and biportal endoscopic (BELD) approaches, as well as between transforaminal and interlaminar access routes. Results: Of 6891 articles, 5469 unique titles/abstracts were screened, yielding 87 studies (3238 patients) for final synthesis. Compared to open microdiscectomy, ELMD patients were more often male, younger, of lower BMI, and had more comorbidities. They typically presented with shorter symptom duration and predominant radiculopathy. ELMD was performed most at L3–L4 and L4–L5. Post-operatively, ELMD patients had significantly lower VAS Leg Pain scores at 1 day and 1 year and reduced recurrence rates. ELMD was associated with lower recurrence rates and correspondingly lower revision surgery rates, with dural tears and wound infections trending lower compared to open surgery. Compared to non-endoscopic MIS, pre- and post-operative characteristics were similar. BELD patients more often had longer symptom duration, motor weakness, and hyporeflexia than FELD patients. Conclusions: ELMD patients demonstrate favorable pain relief and reduced recurrence versus open surgery, with outcomes comparable to MIS. These findings support ELMD as a less invasive alternative within the MIS spectrum.

Healthcare access in Latin America is highly unequal, with rural and peri-urban populations disproportionately excluded from essential and specialized services. To address the persistent gaps often obscured by conventional urban–rural classifications, this study developed a machine learning framework integrating the Functional Urban Area (FUA) model with Density-Based Spatial Clustering of Applications with Noise (DBSCAN) and Shannon entropy optimization to refine urbanization gradients and quantify inequities across 11 countries. High-resolution population density data from the Meta High Resolution Settlement Layer (HRSL, 2020) and CIESIN’s Gridded Population of the World (GPWv4, rev. 11), combined with healthcare facility locations from Healthsites.io, were processed in R to generate population-facility networks. Entropy optimization dynamically determined country-specific DBSCAN distance thresholds, ensuring representative clustering of functional urban and rural areas. Facilities were categorized by care level, and per-capita densities were compared across clusters. Results showed that entropy-optimized DBSCAN improved spatial precision over traditional approaches and revealed systemic urban bias: Peru, Chile, and Venezuela had the lowest hospital densities, while Ecuador, Bolivia, and Paraguay displayed the strongest rural deficits in primary care. Specialized services were overwhelmingly concentrated in urban clusters. This reproducible framework establishes a quantitative baseline for healthcare inequities, providing data-driven insights to inform the design of decentralized strategies to improve equitable access to care across Latin America.