Comparing one vs. two grafts in transforaminal lumbar interbody fusion: clinical and radiographic outcomes

The choice of structural grafts for transforaminal lumbar interbody fusion (TLIF) may influence clinical and radiographic outcomes. It remains unclear whether using one versus two grafts per level affects postoperative results.

To compare clinical and radiographic outcomes in patients undergoing one- or two-level TLIF with either one or two structural grafts per level.

This is a single-center post hoc analysis of prospectively collected data (October 2011-April 2017). The study allocated subjects who underwent one- or two-level TLIF into two groups based on the number of structural allografts per spinal level. Primary clinical outcomes included Visual Analog Scale, VAS back and leg; Oswestry Disability Index, ODI; Short Form, SF-36 v2, Physical and Mental Component Summary. Secondary radiographic outcomes included fusion rates, lumbar/segmental sagittal alignment, anterior and posterior vertebral body height.

A total of 115 patients were included: 38 and 78 were implanted with one or two grafts per level, respectively. At the 24 months postoperatively, there were no significant differences between the groups in primary clinical and radiographic outcomes, nor complication rates. However, both groups showed statistically significant (p < 0.0001) improvements from baseline across all primary clinical measures at the 24 months follow-up.

One or two structural grafts per level yield comparable clinical and radiographic outcomes in one- or two-level TLIF. When feasible, using a single graft per level may be considered without compromising patient outcomes.