Examination of Clinical and Radiographic Outcomes after Lumbar Interbody Fusion: A Retrospective Analysis of TLIF, MidLIF, and MIS-TLIF Procedures

Introduction: Despite many available surgical techniques, the optimal method to achieve posterior lumbar interbody fusion is unclear. This study compares the efficacy of open transforaminal lumbar interbody fusion (TLIF), minimally-invasive TLIF (MIS-TLIF), and midline lumbar interbody fusion (MidLIF) based on patient-reported outcome measures and radiographic parameters.

Methods: A retrospective review of a prospectively collected multi-institutional spine quality database was performed to examine medical records of patients who received a one- or two-level posterior lumbar interbody fusion from January 2018 through April 2023. Quality of life (QOL) scores including the Oswestry Disability Index (ODI), EuroQol 5 Dimension (EQ-5D), EuroQol Visual Analog Scale (EQ-VAS), and numeric rating scale for back pain (NRS-BP) and leg pain (NRS-LP), were used to assess patient conditions at baseline, 3 months, and 12 months post-surgery. These metrics, along with patient demographics, radiographic measurements, and surgical parameters, were compared across the three treatment modalities.

Results: Of 953 patients meeting criteria, 81 (8.5%) underwent MidLIF, 108 (11.3%) underwent MIS-TLIF, and 764 (80.2%) underwent open TLIF. MIS-TLIF patients had significantly shorter length of stay and less blood loss than MidLIF (p < 0.001; p < 0.001) and open TLIF patients (p < 0.001; p < 0.001). In single-level fusion patients, the open TLIF procedure yielded significantly higher construct lordosis at 12-month follow-up compared to MidLIF (p = 0.017). Fusion rates were highest among open TLIF patients and were significantly higher than MIS-TLIF (p < 0.01). Changes in QOL scores at 3- and 12-month follow-ups were similar between groups, excluding NRS-LP at 3 months, which improved the most in the open TLIF cohort and was significantly higher than the MIS-TLIF cohort (p = 0.013).

Conclusion : Our analysis shows that MidLIF, MIS-TLIF, and open TLIF techniques all provide similar, durable improvement in change from baseline QOL scores. While the open TLIF cohort had the highest radiographic fusion rate and most improved segmental lordosis, fusion rates and lordosis measures were high among all groups. These findings provide insight on the variability of each technique, which can inform surgeons in determining the optimal treatment modality.