Midline Lumbar Interbody Fusion (MIDLIF) Is Associated with Decreased Operative Time, Blood Loss, and Length of Stay, Compared to Conventional Transforaminal Lumbar Interbody Fusion (TLIF)

Introduction: Transforaminal lumbar interbody fusion (TLIF) is a commonly performed surgical technique for treatment of symptomatic mobile lumbar spondylolisthesis refractory to conservative therapies. Midline lumbar interbody fusion (MIDLIF) utilizing cortical bone trajectories has been described as a less invasive alternative fixation technique to reduce invasiveness of the approach and facilitate faster recovery.

Methods: A retrospective review was performed of all consecutive single-level MIDLIFs performed from 2019-2022 and compared to a cohort of conventional open TLIFs performed in 2018. Baseline demographics were extracted from the medical record and peri-operative characteristics were extracted including operative time, estimated blood loss, length of stay, and discharge disposition. Statistical group analysis was performed using paired t-test.

Results: A total of 69 patients underwent single-level MIDLIF between 2019-2022. Baseline demographics were not significantly different between the MIDLIF and TLIF cohorts. Mean operative time was 195 +/- 38 minutes in the MIDLIF group (range 127-328 minutes), shorter than the conventional TLIF group (mean 220 +/- 37 minutes), p< 0.05. Mean estimated blood loss was 167 +/- 110 ml in the MIDLIF group, significantly less than the conventional TLIF group (mean 305 +/- 175 ml), p< 0.05. Mean length of stay was 74 +/- 32 hours in the MIDLIF group (range 1-10 days), significantly less than the conventional TLIF comparison group (mean 88 +/- 24 hours), p< 0.05. Screw trajectory was converted to traditional pedicle screw placement in two patients (2.8%). In three patients (4.3%), the disc space was not accessible due to severity of disc degeneration and posterior instrumented fusion without interbody was performed.

Conclusion : MIDLIF with cortical bone trajectories is an alternative to conventional open TLIF for symptomatic single-level mobile spondylolisthesis and is associated with decreased estimated blood loss, decreased operative time, and decreased length of stay.