Outcome Analysis for Minimally Invasive Spine Surgery and Navigation

STUDY RATIONALE AND PRIMARY OBJECTIVE/HYPOTHESIS To assess the clinical and radiographic outcome of spinal fusion procedures using Silicate-Substituted Calcium Phosphate (Si-CaP), a newer-generation of synthetic ceramics designed to maximize osteoinduction and osteoconduction.

STUDY DESIGN Retrospective Study

PURPOSE OF THE STUDY Providing compelling evidence for the efficacy of Si-CaP in terms of resulting in satisfactory fusion.

SUMMARY OF METHODS A prospectively collected database will be reviewed retrospectively, to retrieve data of 200 patients who have undergone different spinal fusion procedures using Silicate-Substituted Calcium Phosphate (Si-CaP). An average follow up duration of at least 12 months will be considered. Clinical outcomes will be assessed using the visual analog scale (VAS), Oswestry Disability Index (ODI), and Neck Disability Index (NDI). Pre-operative scores will be compared to the latest follow-up scores. A board certified Neuro-radiologist will assess the fusion rate. Fusion will be determined by the presence of bony bridging on 2 consecutive sections in at least 2 planes on computed tomographic imaging.

SECONDARY ENDPOINTS AND EXPECTED RESULTS The purpose of this study is to evaluate the level of clinical and radiographic improvement in patients implanted with Silicate-Substituted Calcium Phosphate (Si-CaP) as a bone graft substitute material for spinal fusions. More comprehensive long term studies will be able to provide compelling evidence for the efficacy of Si-CaP in terms of resulting in satisfactory fusion. They can more strongly support the previously published data implying that Si-CaP can be utilized as an alternative to autogenous bone graft in spinal arthrodesis procedures.

Inclusion criteria

• Patients with different spinal fusion procedures (including axial lumbar interbody fusion, transforaminal lumbar interbody fusion, extreme lateral interbody fusion, posterior cervical fusion, and anterior discectomy and fusion using Silicate-Substituted Calcium Phosphate as a bone graft substitute.

Exclusion criteria

• Utilization of any other bone extenders in addition to Si-CaP as a bone graft substitute.