A prospective randomized comparison of coralline hydroxyapatite with autograft in cervical interbody fusion

Abstract

Study Design. A prospective randomized trial with independent clinical and radiographic outcome review of patients receiving either hydroxyapatite or tricortical iliac crest graft for cervical interbody fusion was conducted. Objective. To determine whether coralline-derived hydroxyapatite is a suitable bone graft substitute in cervical interbody fusion. of Background Data. Tricortical iliac crest bone is the gold standard graft material for cervical interbody fusion. Various bone substitutes have been used for this procedure to avoid potential donor site morbidity. ProOsteon 200 is a coralline-derived hydroxyapatite product, the use of which remains unclear for cervical interbody fusion. Methods. In this study, 29 patients undergoing anterior cervical fusion and plating were randomized to receive either ProOsteon 200 or iliac crest grafts. The SF-36 and Oswestry Disability index were used to measure clinical outcome. Postoperative radiographs were analyzed for graft fragmentation, loss of height, angular alignment, and hardware failure to assess structural integrity of the graft material. Plain radiographs and computed tomography scans were used to evaluate fusion. Results. Both the ProOsteon 200 and iliac crest groups demonstrated significant improvement in clinical outcome scores. There was no significant difference in clinical outcome or fusion rates between the two groups. Graft fragmentation occurred in 89% of the hydroxyapatite grafts and 11% of the autografts (P = 0.001). Significant graft settling occurred in 50% of the hydroxyapatite grafts, as compared with 11% of the autografts (P = 0. 009). One patient in the ProOsteon 200 group required revision surgery for graft failure. Conclusions. ProOsteon 200 does not possess adequate structural integrity to resist axial loading and maintain disc height or segmental lordosis during cervical interbody fusion.