Spondylodiscitis treated with freeze-dried bone allograft alone or combined with autograft: A randomized and blinded trial

Purpose: To compare the bone fusion of freeze-dried allograft alone versus freeze-dried allograft combined autograft in spinal instrumentation due to spondylodiscitis. Methods: A randomized prospective trial of patients with spondylodiscitis treated with surgical debridement and spinal fixation with freeze-dried bone allograft and autograft (Group 1) or freeze-dried bone allograft alone (Group 2) was performed. Patient follow-up was assessed with a CT-scan for bone fusion; consecutive serum inflammatory marker detection (C-reactive protein, [CRP], and erythrocyte sedimentation rate, [ESR]) and clinical assessment (pain, functional disability, and spinal cord injury recovery) were other outcome parameters. The primary outcome was the grade of bone allograft integration with the scale of Tan (which ranges from 1 to 4, with lower scores indicating a better fusion rate) at 1 year after surgery. Results: A total of 20 patients were evaluated, 13 (65%) men and 7 (35%) women with a mean age of 47.2 (±14.3) years. Homogeneous distribution of demographic data was observed. A similar satisfactory bone graft fusion grade was observed in both graft groups at 1 year after surgery (p = 1.0000). Serum inflammatory markers gradually decreased in both groups after surgical intervention (CRP, p < 0.001; ESR, p < 0.01). At one-year follow-up, gradual improvement of pain, functional disability, and neurological spinal injury recovery in both graft groups were achieved. Conclusion: Freeze-dried allograft alone could be a therapeutic option for spinal fixation surgery due to spondylodiscitis since it achieves a satisfactory graft fusion rate and clinical improvement. Level of Evidence: Level 1. Treatment ClinicalTrials.gov register: NCT03265561