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.