Objectives:

To compare patient-reported outcomes and radiographic outcomes between using PEEK and TiPEEK as an interbody cage in patients who underwent MIS-TLIF.

Methods:

Eighty-six patients who underwent 1-2 levels of MIS-TLIF were randomly allocated to receive a TiPEEK or PEEK cage. Patient-reported outcomes were recorded using Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and EuroQoL-5D-5L. Postoperative radiographs and CT were assessed for spinal fusion and cage subsidence.

Results:

The eligible 82 patients (41 patients, 49 operated levels in TiPEEK and 41 patients, 50 operated levels in PEEK group) were included in the final analysis. Over total follow-up, mean difference in VAS back and leg pain scores between TiPEEK vs. PEEK group was -0.04 (95%CI -0.5 to 0.4; P=0.85) and -0.12 (95%CI -0.6 to 0.3; P=0.62), respectively. The mean difference in ODI scores was -0.71 (95%CI -3.8 to 2.4; P=0.65), and mean difference in EQ-5D-5L was 0.03 (95%CI -0.01 to 0.06; P=0.11) in TiPEEK group vs. PEEK group as a reference. TiPEEK showed significantly higher fusion rates than PEEK at 6-month (91.8% vs. 76%; P=0.03), but no difference at 12-month post-operation. There was no significant difference in cage subsidence rates between two groups.

Conclusions:

The patient-reported outcomes showed significant improvements at 6- and 12-month post-operation following MIS-TLIF; the differences in those with TiPEEK vs. PEEK cages were minimal with tight confidence intervals. Fusion rates in both groups were ≥90%, with TiPEEK cages showing higher fusion rates at six months after the procedure.