407 Results of Biphasic Calcium Phosphate Bone Graft With Submicron-Sized Needle-Shaped Surface Topography as Standalone Alternative to Autograft Are Favorable in a Prospective, Multi-center, Randomized, Intra-patient Controlled Trial

INTRODUCTION: Pseudoarthrosis after spinal fusion is an important complication leading to revision spine surgeries. Iliac Crest Bone Graft is considered the gold standard, but with limited availability and associated co-morbidities, spine surgeons often utilize alternative bone grafts. METHODS: Adult patients indicated for instrumented PLF of one to six levels from T10-S2 were enrolled at five participating centers. After preparation of the bone bed, one side was grafted with 10 cc of autograft per level containing a minimum of 50% iliac crest bone. The other side was grafted with 10 cc of BCP < µm granules standalone. In total, 71 levels were treated. Prospective follow-up included a fine-cut (<1 mm) Computerized Tomography (CT) at one year. Fusion was systematically scored as fused or not fused per level per side by two spine surgeons blinded for the procedure. RESULTS: The first fifty patients enrolled are included in this analysis. Average age was 57 years old, with 60% female and 40% male. The diagnoses included deformity (56%), structural instability (28%), and instability from decompression (20%). The fusion rate determined by fine-cut CT for BCP < μm was 76.1% (54/71 levels), which compared favorably to the autograft fusion rate of 43.7% (31/71 levels). Fusion of the BCP < μm side was not contingent upon fusion of the autograft side, as 36.6% (26/71) of levels fused on the BCP < μm side but did not fuse on the autograft side. Binomial modeling revealed that the odds of fusion of BCP < μm was 2.54 times higher than that of autograft. CONCLUSIONS: These data, aiming to determine non-inferiority of standalone BCP < μm as compared to autograft for PLF, are promising. Ongoing studies with additional patients are forthcoming.