Examination of clinical and radiographic outcomes after lumbar interbody fusion: a retrospective analysis of TLIF, MidLIF, and MIS-TLIF procedures

OBJECTIVE: Despite many available surgical techniques, the optimal method to achieve posterior lumbar interbody fusion (PLIF) 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 institutional spine quality database was performed to examine the medical records of patients who received a 1- or 2-level PLIF from January 2018 through April 2023. Quality of life (QOL) scores, including the Oswestry Disability Index (ODI), EuroQol 5-Dimension Index (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 after surgery. These metrics, along with patient demographics, radiographic measurements, and surgical parameters, were analyzed and compared across the three treatment modalities. RESULTS: Of the 953 patients who met 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 hospital length of stay and less blood loss compared with MidLIF (both p < 0.001) and open TLIF patients (both p < 0.001). In patients with single-level fusion, open TLIF yielded significantly higher construct lordosis at 12 months postoperatively compared with MidLIF (p = 0.017), although average corrections to construct lordosis were similar across groups. Fusion rates were highest among the open TLIF group and were significantly higher (p < 0.01) than the MIS-TLIF group. Changes in QOL scores at the 3- and 12-month follow-ups were similar between procedure types, with the exception of 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). CONCLUSIONS: This analysis shows that MidLIF, MIS-TLIF, and open TLIF techniques all provide similar durable improvement in change from baseline ODI, EQ-5D, EQ-VAS, NRS-BP, and NRS-LP scores, as well as similar corrections to segmental lordosis. While open TLIF had the highest radiographic fusion rate, fusion rates were high among all groups. These findings provide insight on the variability of each technique, which can inform surgeons in determining the modality of treatment best suited for their patient's condition and needs.