Feasibility of CaO-SiO₂-P₂O₅-B₂O₃ Bioactive Glass Ceramic Cage in Anterior Cervical Diskectomy and Fusion

Background: CaO-SiO₂-P₂O₅-B₂O₃ bioactive glass ceramic (BGC) is known to chemically bond with bones by forming a hydroxyapatite layer and inducing osteoblastic differentiation. This study was conducted to compare the clinical outcomes, radiographic outcomes, and safety of a CaO-SiO₂-P₂O₅-B₂O₃ BGC cage in anterior cervical diskectomy and fusion (ACDF) with those of an allograft interbody spacer.

Methods: A total of 63 patients who underwent 2-level ACDF to treat degenerative cervical radiculopathy/myelopathy were reviewed. Results from 26 patients who were recruited prospectively using CaO-SiO₂-P₂O₅-B₂O₃ BGC as a cage material (BGC group) were compared with a historical control group of 37 patients who underwent surgery using an allograft (allograft group). Fusion rates, subsidence, and adjacent segment degeneration were compared between the groups. Demographic data, fusion rates, visual analog scale (VAS) scores for neck or arm pain, Neck Disability Index (NDI) scores, and complications were also compared.

Results: Fusion rates were 88.5% when assessed by interspinous motion and 92.3% when assessed by intragraft bone bridging in the BGC group at 12-month follow-up. The neck pain or arm pain VAS scores and NDI scores significantly improved in both groups. No material-related complications were observed in the BGC group, such as graft resorption and breakage. Fusion rates, subsidence, neck pain or arm pain VAS scores, and NDI scores did not significantly differ between the BGC and allograft groups.

Conclusions: CaO-SiO₂-P₂O₅-B₂O₃ BGC cage was effective and safe when used in ACDF, conferring a high fusion rate and favorable clinical outcomes similar to those of the allograft.