Reassessing the Clock in Cauda Equina Syndrome: A Systematic Review and Meta-analysis of Surgical Timing and Outcomes.

Abstract

Despite universal advocacy for urgent decompression in cauda equina syndrome (CES), the literature remains inconsistent regarding the optimal surgical timing. Heterogeneous diagnostic criteria, variable timing definitions, and a mix of clinical cohorts and national datasets have contributed to ongoing debate over 24- and 48-hour thresholds. To evaluate whether timing of decompression influences urinary, neurological, functional, and inpatient outcomes in CES, and to identify clinically meaningful temporal thresholds. Systematic review and meta-analysis of comparative cohort studies conducted according to PRISMA 2020 and MOOSE guidelines. Fifteen comparative studies involving 26,627 adults undergoing decompression for degenerative CES. Urinary and bowel recovery, motor and sensory improvement, pain (VAS), disability (ODI), return to work, complications, in-hospital mortality, length of stay, and discharge disposition. Five databases were searched from inception through November 2025. Eligible studies compared at least two discrete time-to-surgery intervals. Risk of bias was assessed with ROBINS-I. Random-effects models were used for pooled analyses with prespecified subgroup analyses by CES subtype, timing definition, etiology, and follow-up duration. Across clinical cohorts, decompression within 48 hours of symptom onset significantly improved urinary recovery (pooled OR ≈2.3), motor function, and overall neurological outcomes compared with >48 hours. Incomplete CES showed a strong timing effect, whereas retention-type CES demonstrated no significant timing-related difference. National database studies showed increased mortality, longer length of stay, and worse discharge disposition when surgery was delayed beyond 48 hours. No consistent advantage was observed for <24 hours compared with 24-48 hours across neurological, urinary, functional, or inpatient outcomes. Early timing effects were most pronounced for short-term recovery; at ≥12 months, differences between early and delayed groups attenuated, and baseline bladder status was the dominant prognostic factor. Comparative evidence identifies a clinically meaningful threshold at approximately 48 hours from symptom onset for optimizing early urinary and neurological outcomes in CES, particularly in incomplete presentations. Surgery within the first 24 hours does not consistently outperform surgery performed between 24 and 48 hours. Long-term outcomes are driven primarily by preoperative bladder function rather than surgical timing. Clinical pathways should emphasize expedited diagnosis and decompression within 48 hours, with greatest urgency for patients who retain voluntary voiding.