Comparative Analysis of Allograft Versus Hydroxyapatite in Anterior Cervical Discectomy and Fusion

STUDY DESIGN: This is a retrospective study. OBJECTIVE: To evaluate and compare the clinical efficacy and fusion outcomes of allograft versus hydroxyapatite (HA) as bone graft materials in anterior cervical discectomy and fusion (ACDF) surgery. SUMMARY OF BACKGROUND DATA: ACDF is used for cervical disc herniation treatment; however, there is no consensus on the optimal bone graft material, particularly between allograft and hydroxyapatite. METHODS: This retrospective study included patients who underwent ACDF at the Third Affiliated Hospital of Southern Medical University between January 2015 and December 2019. A total of 63 patients met the inclusion criteria and were divided into 2 groups: the allograft group (n=39) and the HA group (n=24). Clinical outcomes were assessed using the Visual Analogue Scale (VAS), Japanese Orthopaedic Association (JOA) score, and Neck Disability Index (NDI). Cervical spine radiographs were utilized to evaluate fusion status, intervertebral height, and sagittal alignment parameters. RESULTS: Both groups demonstrated significant postoperative improvement in VAS, JOA, and NDI scores compared with preoperative values. The magnitude of improvement was similar between the 2 groups, the allograft group exhibited superior final VAS, JOA, and NDI scores relative to the HA group. Radiographic analysis revealed a significantly lower fusion rate and score in the HA group. The incidence of cage subsidence was higher in the HA group, although no significant difference in intervertebral height was observed between groups. Notably, 6 patients (25.0%) in the HA group experienced fusion failure requiring revision surgery, of whom 3 underwent reoperation. No fusion failure or revision surgery was reported in the allograft group. CONCLUSION: ACDF remains a widely accepted and effective treatment for cervical disc herniation. While both graft types provide symptomatic relief and functional recovery, the allograft demonstrates superior performance in terms of fusion rate, structural integrity, and lower revision risk.