Early Fusion Status after Posterior Lumbar Interbody Fusion with Cortical Bone Trajectory Screw Fixation: A Comparison of Titanium-Coated Polyetheretherketone Cages and Carbon Polyetheretherketone Cages
- Author:
Hironobu SAKAURA
1
;
Atsunori OHNISHI
;
Akira YAMAGISHI
;
Tetsuo OHWADA
Author Information
- Publication Type:Original Article
- Keywords: Degenerative lumbar spondylolisthesis; Posterior lumbar interbody fusion; Cortical bone trajectory screw technique; Titanium-coated polyetheretherketone cage; Carbon polyetheretherketone cage
- MeSH: Carbon; Cohort Studies; Follow-Up Studies; Humans; Incidence; Pathology; Pedicle Screws; Retrospective Studies; Risk Factors
- From:Asian Spine Journal 2019;13(2):248-253
- CountryRepublic of Korea
- Language:English
- Abstract: STUDY DESIGN: Retrospective cohort study. PURPOSE: We recently reported that when compared to posterior lumbar interbody fusion (PLIF) using traditional pedicle screw fixation, PLIF with cortical bone trajectory screw fixation (CBT-PLIF) provided favorable clinical outcomes and reduced the incidence of symptomatic adjacent segment pathology, but resulted in relatively lower fusion rates. Since titanium-coated polyetheretherketone (PEEK) cages (TP) could improve and accelerate fusion status after CBT-PLIF, early fusion status was compared between CBT-PLIF using TP and carbon PEEK cages (CP). OVERVIEW OF LITERATURE: A systematic review demonstrated that clinical studies at this early stage show similar fusion rates for TP compared to PEEK cages. METHODS: We studied 36 consecutive patients undergoing CBT-PLIF with TP (TP group) and 92 undergoing CBT-PLIF with CP (CP group). On multiplanar reconstruction computed tomography (MPR-CT) at 6 months postoperatively, vertebral endplate cysts (cyst signs) were evaluated and classified as diffuse or local cysts. Early fusion status was assessed by dynamic plain radiographs and MPR-CT at 1 year postoperatively. RESULTS: The incidences of cyst signs, diffuse cysts, and early fusion rate in the TP and CP groups were 38.9% and 66.3% (p<0.01), 16.7% and 32.6% (p=0.07), and 83.3% and 79.3% (p>0.05), respectively. Combining the two groups, 22 of 36 patients with diffuse cysts had nonunion at 1-year follow-up, compared to only three of 92 patients with local cysts or without cyst signs (p<0.01). CONCLUSIONS: Despite having fewer patients with endplate cysts at 6 months (a known risk factor for nonunion), the TP group had the same fusion rate as the CP group at 1-year follow-up. Thus, TP did not accelerate the fusion process after CBT-PLIF.