Minimally invasive versus mini-open transforaminal lumbar interbody fusion in managing low-grade degenerative spondylolisthesis

Data background

Because the traditional open-TLIF approach has several drawbacks, minimally invasive surgery (MIS) approaches for TLIF (MISTLIF) have been developed to speed up recovery after surgery and minimize pressure on the para-spinal muscles, necessitating a cost-utility analysis for comparison in healthcare reforms.

Objectives and aim of the work

This study aimed to compare the radiological and clinical parameters between mini-open TLIF and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery in patients with single-level lumbar degenerative spondylolisthesis.

Hypothesis

This study hypothesizes that both minimally invasive and mini-open methods using sublaminar trimming laminoplasty (SLTL) (while preserving midline structures) and interbody cages have comparable mid- and long-term clinical and radiological outcomes.

Methods

Retrospective analyses were performed on 120 patients who underwent single-level TLIF procedures with a minimum of two years of follow-up utilizing either the mini-open (n = 60) or MIS (n = 60) technique. Records of the operation's time frame, intraoperative fluoroscopy, blood loss, postoperative drainage volume, duration of bed rest, and complications were recorded. The Oswestry Disability Index (ODI) and visual analog scale (VAS) scores for both groups were utilized to assess improvements in clinical scores, and t tests were employed to statistically compare the outcomes. For comparison, radiological parameters, including lumbar lordosis, pelvic incidence (PI), and localized lordosis at the index level, were measured preoperatively, postoperatively, and at the final follow-up. To assess postoperative interbody fusion, the Bridwell grading system was used.

Results

In the Mini-open TLIF group, the average follow-up time was 24.91 ± 5.7 months, while in the MIS-TLIF group, the average follow-up time was 25.15 ± 4.2 months. In the MIS-TLIF group, the mean operation and radiological time were longer. However, compared to the Mini-open TLIF group, the MISTLIF group experienced less blood loss and a shorter hospital stay. The MIS-TLIF group outperformed the Open-TLIF group in terms of the VAS score for back pain and the ODI at less than 6 months following surgery, and the differences were statistically significant. However, at the final follow-up, there were no statistically significant differences in the VAS score for the back between the two groups, but the ODI score was significantly greater in the MIS-TLIF group. Both groups' lumbar lordosis and focal lordosis significantly improved at the index level, with the Mini-open-TLIF group showing more focal lordosis. The interbody fusion rate did not significantly differ between the two groups.

Conclusion

MIS-TLIF and mini-open-TLIF can be surgically effective in treating single-level degenerative lumbar spine spondylolisthesis.