Bilateral versus Unilateral Decompression in Single-Level Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis: A Retrospective Comparative Study

OBJECTIVE: To assess if pre-emptive bilateral approach decompression (BAD) lowers early neural events and enhances very-early recovery versus unilateral approach decompression (UAD) in single-level transforaminal lumbar interbody fusion for Meyerding grade I degenerative spondylolisthesis. METHODS: Single-center retrospective study (2015-2022) with ≥24-month follow-up. Allocation by practice evolution: UAD (2015-2018) and BAD (2019-2022), limited to uniform mild-to-moderate contralateral risks. PRIMARY ENDPOINTS: very-early recovery (visual analog scale/Oswestry Disability Index/Japanese Orthopaedic Association at postoperative day [POD] 1/POD7) and neural complications. RESULTS: Analyzed 208 patients (UAD n = 102; BAD n = 106). BAD had longer operative time (114 ± 10 vs. 75 ± 9 minutes; P < 0.001). BAD improved very-early recovery: visual analog scale POD7 4.2 ± 0.6 versus 5.0 ± 0.7 (P < 0.001). Neural events were lower in BAD: early postoperative radicular pain 1.9% versus 9.8% (P = 0.017) and contralateral aggravation 0% versus 4.9% (P = 0.027). Two-year Japanese Orthopaedic Association recovery was similar (73% vs. 73%). CONCLUSIONS: In grade I spondylolisthesis transforaminal lumbar interbody fusion, BAD reduces early neural events and boosts very-early recovery without added blood loss or fusion compromise.