(I-686) Results of Biphasic Calcium Phosphate Bone Graft with Submicron-Sized Needle-Shaped Surface Topography as Standalone Alternative to Autograft Are Favorable in an Ongoing Prospective RCT

Introduction: Pseudoarthrosis after spinal fusion can lead to revision spine surgeries. The aim of this study was to determine the non-inferiority of a novel submicron-sized needle-shaped surface biphasic calcium phosphate (BCP<µm) used standalone, as compared to autograft in instrumented posterolateral spinal fusion.

Methods: Adult patients undergoing instrumented posterolateral spinal fusion of one to six levels from T10-S2 were enrolled at five participating centers. After instrumentation and preparation of the bone bed, the randomized allocation side of the graft type was disclosed. One side was grafted with 10 cc of autograft per level (50% iliac crest). The other side was grafted with 10 cc of BCP<µm granules standalone. Prospective follow-up included adverse events, Oswestry Disability Index (ODI), and a fine-cut ( < 1mm) Computerized Tomography (CT) at one year. Fusion was scored 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 (27-79 years), 60% female and 40% male. The diagnoses included deformity (56%), structural instability (28%), and instability from decompression (20%). The fusion rate determined by CT for BCP<μm was 76.1% (54/71 levels), which compared favorably to the autograft fusion rate of 43.7% (31/71 levels). Statistical analysis through binomial modeling showed that the odds of fusion of BCP<μm was 2.54 times higher than that of autograft. Oswestry Disability Index (ODI) score decreased from a mean of 46.0 (±15.0) to a mean of 31.7 (±16.9), and 52.4% of patients improved with at least 15-point decrease.

Conclusion : This data to determine non-inferiority of standalone BCP<μm to autograft is promising. Ongoing studies are forthcoming.

How to Improve Patient Care: Pseudoarthrosis can lead to pain, disability, and revision spine surgeries. Utilizing a bone graft that is both efficacious and cost-effective can decrease the burden of non-union and revision surgery and add financial value to the healthcare system.