Hollow bone cement filled with impacted cancellous bone as a substitute for bone grafts in cervical spine fusion

Autogenous iliac crest bone is the gold standard for graft material in cervical spinal fusion, but a high incidence of donor site morbidity has been reported. Therefore, to achieve a better fusion rate and decrease the rate of donor site morbidity, we used a novel method whereby hollow bone cement filled with impacted cancellous bone is used as a substitute for bone graft in cervical interbody fusion. From 2003 to 2004, 21 patients with cervical spinal disorders who were treated using this method were included in this study. Fourteen patients underwent single-level grafts and seven underwent two-level grafts. Evaluation included a monthly clinical and X-ray examination for the first 3 months, and then follow-up every 3 months thereafter. Multiple-slice computed tomography (CT) scan with reconstruction to evaluate the viability of the bone graft was performed when evidence of bone fusion was found on X-ray. The mean age of the patients was 59 years (range 27-79). The mean follow-up period was 19 months (13-24 months). Evidence of impacted cancellous bone bridging the adjacent vertebral body was observed in all patients at the 6-month follow-up based on X-rays and reconstructive CT scans. No severe donor site morbidity occurred. One patient experienced hardware failure due to screw fracture, but a reconstructive CT scan revealed well-bridged cancellous bone between the vertebral bodies. Hollow bone cement filled with impacted cancellous bone could be an alternative material for cervical spine interbody fusion. Using this method, we found not only satisfactory growth of cancellous bone in the holes of the bone cement, but also low morbidity in the donor site. However, for this method, the long-term stability, potential complications, and the necessity of instrumentation all require further investigation.