Polyetheretherketone Cage filled with Beta-Tricalcium Phosphate versus Autogenous Tricortical Iliac Bone Graft in Anterior Cervical Discectomy and Fusion

ABSTRACT

OBJECTIVE: To compare clinical and radiologic results of two graft materials for anterior cervical discectomy and fusion (ACDF) with rigid plate fixation for cervical spinal disorder. METHODS: Twenty-eight patients treated with single-level ACDF with rigid plate fixation were retrospectively reviewed. They were divided into twogroups Polyetheretherketone (PEEK) cage filled with beta-tricalcium phosphate (beta-TCP) in Group A (n=15); and autogenous tricortical iliac bone graft in group B (n=13). The average follow-up durations were 16.3 months and 19.90 months for group A and group B, respectively. Clinical outcomes were graded using the visual analogue scale (VAS) score and neck disability index (NDI). Interbody height, segmental kyphotic angle and overall kyphotic angle were used as parameters to evaluate radiographic change in the 2 treatment groups. RESULTS: Clinically, VAS scores and NDI significantly improved after the surgery in both groups (p0.05). The fusion rates after 12 months in group A and B were 93.3% and 100%, respectively. One case of cage subsidence which resulted in pseudoarthrosis occurred in group A. However, statistical analysis did not show difference in fusion rate between the two groups (p>0.05). CONCLUSION: ACDF using PEEK cage filled with alpha-TCP showed comparable clinical and radiologic results with the standard of autogenous iliac bone graft. However, pseudoarthrosis did occur even with rigid plate and screw fixation in ACDF using PEEK cage filled with beta-TCP. There is high likelihood of emerging pseudoarthrosis, especially when there is a sign of chronic and progressive cage subsidence.