Radiographic Fusion Outcomes for Trinity Cellular Based Allograft versus Local Bone in Posterolateral Lumbar Fusion

Abstract

Introduction: Cellular-based autograft (CBA) is being used in posterolateral lumbar arthrodesis as a fusion supplementation alternative. Objective: To assess radiographic fusion in patients undergoing posterolateral lumbar fusion with unilateral Trinity CBA compared with contralateral local bone autograft as an internal control. Methods: A single surgeon's practice database was interrogated for consecutive patients undergoing primary posterolateral lumbar fusion with Trinity from 2018 to 2021. Patients had Trinity applied unilaterally, with local bone autograft applied contralaterally. Fusion was assessed postoperatively by using CT after 9 months. Demographics and patient-reported outcome measures were collected preoperatively and up to 12 months postoperatively. Results: Thirty-nine patients were included. There were 81 attempted fusion levels. Overall fusion rate, defined as bony bridging on at least one side of a given level for all levels fused, was 85.2% of patients. No statistically significant difference was observed in fusion rates between CBA versus local bone (79.0% versus 76.54% of levels attempted, respectively, P = 0.3527). Oswestry Disability Index improved by 3 months (P = 0.0152) and was maintained. Two patients required revision for symptomatic nonunion. Conclusions: Similar radiographic fusion rates were achieved with Trinity and local bone. Trinity is a viable alternative to local bone in posterolateral lumbar fusion.