Clinical and Functional Outcomes of Delta Large-Channel Endoscopic Lumbar Decompression: A Systematic Review and...

Background: Delta large-channel endoscopic decompression is an emerging, minimally invasive approach for lumbar degenerative disease, but its comparative effectiveness and perioperative performance have not been comprehensively synthesized. We performed a systematic review and meta-analysis to evaluate clinical, functional, and safety outcomes of Delta large-channel endoscopy relative to established decompression techniques. Methods: PubMed, Embase, and Scopus were searched from database inception through July 2025 (PROSPERO #CRD420251107750). Peer-reviewed English-language studies reporting extractable outcomes after Delta large-channel endoscopic surgery in adults were included. Random-effects meta-analyses were used for pooled comparisons. Results: Nine studies met the inclusion criteria, comprising 737 patients overall, including 379 treated with Delta large-channel endoscopy and 358 treated with comparator procedures. Reported outcome assessment generally ranged from 1 week to 12 months postoperatively, or variable latest follow-up timepoints, and mean follow-up was inconsistently reported. All studies originated in China and included five retrospective cohorts, two randomized controlled trials, one prospective cohort, and one case series. The pooled mean operative time for Delta procedures was 88.28 min (95% CI, 79.24-97.31), pooled mean intraoperative blood loss was 24.58 mL (95% CI, 11.14-38.02), and pooled mean hospital stay was 4.59 days (95% CI, 2.87-6.31). Compared with microscopic, endoscopic, and open techniques, Delta large-channel endoscopy showed no statistically significant differences in operative time (MD = 6.95 min, 95% CI: -11.51-25.40 min; p = 0.4037), intraoperative blood loss (MD, -40.62 mL; 95% CI, -83.68-2.44; p = 0.0598), 3-month ODI change from baseline (MD, 1.26; 95% CI, -2.17-4.69; p = 0.3661), or complication rates (OR, 0.67; 95% CI, 0.40-1.12; p = 0.1094). Delta procedures were associated with shorter hospital stay (MD, -1.69 days; 95% CI, -2.83 to -0.56; p = 0.0122) and marginally greater improvement in six-month VAS low back pain change from baseline (MD, 0.28; 95% CI, 0.26-0.29; p = 0.0002), though clinically insignificant. The pooled complication rate for Delta procedures was 6.0% (95% CI, 4-10%) and reported rates of excellent or good MacNab outcomes ranged from 80 to 93% across Delta cohorts. Conclusions: Delta large-channel endoscopy may provide clinical and functional outcomes comparable to established decompression techniques, with similar safety and potential perioperative benefits, including shorter hospitalization. However, these findings are based on limited, low-certainty evidence with high heterogeneity and should be interpreted as exploratory rather than definitive. Additional multicenter studies with longer follow-up, broader geographic representation, and higher methodological quality are necessary before definitive conclusions regarding comparative effectiveness can be established.