Endoscopic versus non-endoscopic decompression for degenerative lumbar spinal stenosis in adults: a systematic review and meta-analysis of randomised trials

Introduction Endoscopic decompression may reduce morbidity, but sustained benefits over non-endoscopic surgery remain uncertain. Objective To assess disability, pain and harms in adult randomised comparisons of decompression without fusion. Methods MEDLINE, Embase, CINAHL and the Cochrane Library were searched on 23 September 2026. English-language adult randomised trials comparing endoscopic and non-endoscopic decompression without fusion were eligible. Two reviewers independently selected studies and extracted data. Bias and certainty were assessed with the revised Cochrane risk-of-bias tool and the Grading of Recommendations Assessment, Development and Evaluation approach. Compatible estimates used random-effects models with modified Hartung–Knapp intervals. Registration and scope changes were retrospective (Open Science Framework: https://osf.io/qb9a6/). The review received no funding. Results Sixteen reports described 12 trials allocating 1,212 participants. The protocol-planned 12-month Oswestry Disability Index analysis included four trials (302 participants): mean difference −4.54 points (95% confidence interval −5.95 to −3.13). Zhang F supplied 95.1% of the weight and had reporting concerns. The post hoc sensitivity without that trial included three microscopic comparisons (234 participants): −3.74 (−12.30 to 4.81; low certainty). Six-month disability and exploratory pain analyses were similarly sensitive or uncertain. Nine trials reported 23 durotomies (risk ratio 0.61, 95% confidence interval 0.23 to 1.59; very low certainty). Inconsistent measurement limited blood-loss and reoperation comparisons. Conclusion Endoscopic decompression has not shown a reliable sustained advantage in disability, pain or safety. The small pooled disability benefit depended heavily on one trial with reporting concerns. Procedure selection should consider the required decompression and surgical expertise; these findings do not establish equivalent safety.