A Comparison of Polyetheretherketone and Titanium-Coated Polyetheretherketone in Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Randomized Clinical Trial

To compare patient-reported outcomes and radiographic outcomes between using polyetheretherketone (PEEK) and titanium-coated PEEK (TiPEEK) as an interbody cage in patients who underwent minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).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, Oswestry Disability Index, and EuroQoL-5D-5L. Postoperative radiographs and computed tomography were assessed for spinal fusion and cage subsidence.The eligible 82 patients (41 patients, 49 operated levels in TiPEEK group and 41 patients, 50 operated levels in PEEK group) were included in the final analysis. Over total follow-up, the mean difference in visual analog scale back and leg pain scores between TiPEEK versus PEEK group was -0.04 (95% confidence interval [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 Oswestry Disability Index scores was -0.71 (95% CI, -3.8 to 2.4; P = 0.65), and the mean difference in EQ-5D-5 L was 0.03 (95% CI, -0.01 to 0.06; P = 0.11) in TiPEEK group versus 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 postoperation. There was no significant difference in cage subsidence rates between the 2 groups.The patient-reported outcomes showed significant improvements at 6- and 12-month postoperation following MIS-TLIF; the differences in those with TiPEEK versus PEEK cages were minimal with tight CIs. Fusion rates in both groups were ≥90%, with TiPEEK cages showing higher fusion rates at 6 months after the procedure.