Clinical and Patient-Reported Outcomes after Posterior (PLIF) versus Transforaminal Lumbar Interbody Fusion (TLIF) - A Propensity-Score Matched Cohort Study on 422 Patients with two-Year Follow-up.

Study design This was a dual-center study over an eight-year period on patients undergoing single level fusion surgery with either posterior- (PLIF) or transforaminal lumbar interbody fusion (TLIF). We analyzed prospectively collected pre- and postoperative data from the national Danish surgical spine database (DaneSpine). Objective To compare clinical and patient-reported outcome (PRO) two years after TLIF or PLIF in patients with symptomatic lumbar mechanical disc degeneration. Summary of background data PLIF and TLIF are well-described techniques for treating lumbar mechanical disc degeneration but whether the theoretical differences between the two techniques translate to different clinical outcomes is unknown. Methods The primary outcome was Oswestry Disability Index (ODI) score at two-year follow-up. Secondary outcome measures were scores on the European Quality of Life-5 Dimensions (EQ-5D) and visual analog scale (VAS) and the rate of intraoperative complications. To minimize baseline differences between the groups, propensity-score matching was employed in a 1:1 fashion, balancing the groups on preoperative factors including age, sex, back and leg pain, ODI, EQ-5D and previous spine surgery. Results The matched cohort included 211 patients in each cohort. There was no significant difference between the groups in the mean score on the ODI at two years (PLIF: 33 ± 20 vs. TLIF: 35 ± 20, p = 0.328). We found no statistically significant differences in EQ-5D score (0.54 ± 0.35 vs. 0.51 ± 0.34, p = 0.327), VAS score for back pain (47 ± 32 vs. 48 ± 29, p = 0.570) or leg pain (42 ± 33 vs.41 ± 32, p = 0.936) between the PLIF and TLIF groups, respectively at two-year follow-up. Dural tears occurred in 9.5% in the PLIF group and 1.9% in the TLIF group (p = 0.002) corresponding to a relative risk of 5.0 (95%CI 1.7-14.4). Conclusions We found no significant difference in PRO at two-year follow-up between PLIF and TLIF for the treatment of lumbar disc degeneration. PLIF is associated with a five-times higher risk of dural tears.Level of evidence: 3.