Comparison of Clinical Outcome and Radiologic Parameters in Open TLIF Versus MIS-TLIF in Single- or Double-Level Lumbar Surgeries

Purpose: The objective of this study was to compare clinical and radiologic parameters between minimally invasive surgery–transforaminal lumbar interbody fusion (MIS-TLIF) and open TLIF.

Methods: Data of 145 patients who underwent single- or double-level TLIF procedures with an open (n = 76) or a MIS (n = 69) technique were analyzed. Average operation time, estimated blood loss, and hospital stay were compared between open TLIF and MIS-TLIF. Improvement in clinical scores was analyzed using visual analog scale (VAS) and Oswestry Disability Index (ODI) scores in both groups and statistically compared using t tests. Radiologic parameters, such as lumbar lordosis, focal lordosis at the index level, and pelvic incidence (PI), were calculated at preoperative, postoperative, and final follow-up for comparison. The differences in improvement between open and MIS groups were analyzed using unpaired t tests.

Results: Average follow-up was 35.8 ± 15.4 months in open TLIF and 37.9 ± 14.4 months in MIS-TLIF. The average blood loss and operation times were higher and hospital stay was less in MIS-TLIF compared to open TLIF. VAS scores were improved from preoperative (8.5 ± 0.6) to postoperative (2.1 ± 0.8) and preoperative (8.4 ± 0.8) to postoperative (2.0 ± 0.7) in open TLIF and MIS-TLIF, respectively (P < .0001), and ODI scores were improved from preoperative (55.2 ± 5.2) to postoperative (22.5 ± 4.3) and preoperative (56.7 ± 4.9) to postoperative (22.0 ± 5.0) in open TLIF and MIS-TLIF, respectively (P < .0001). Similarly, there were significant improvements in lumbar lordosis and focal lordosis at the index level with a difference of 3.9° and 2.5°, respectively, in open TLIF and 4.0° and 2.9°, respectively, in MIS-TLIF. However, there were no differences in PI in both groups. There were 9 (11.8%) and 9 (13%) complications encountered in open TLIF and MIS-TLIF, respectively. Two patients from open TLIF and 5 from MIS-TLIF had to undergo revision surgeries without any statistical difference.

Conclusions: Open TLIF and MIS-TLIF are equally efficient surgical techniques with similar clinical and radiologic outcomes. MIS-TLIF is associated with less intraoperative blood loss and hospital stay; however, it increases operation time significantly.