Clinical and radiographic outcomes of hybrid graft in patients with Modic changes undergoing transforaminal lumbar interbody fusion

BACKGROUND: This retrospective study aimed to analyze the influence of Modic changes (MCs) on the clinical and radiographic outcomes of transforaminal lumbar interbody fusion with hybrid graft. METHODS: Clinical data of 89 patients with Modic changes who underwent single-segment transforaminal lumbar interbody fusion between January 2015 and January 2019 at our institution were analyzed. Patients were divided into three groups: the MCs-0 group (no endplate changes; used as the control group), the MCs-1 group, and the MCs-2 group. Clinical and radiological parameters were compared between the three groups. RESULTS: There were no significant between-group differences in age (P = 0.216), sex (P = 0.903), body mass index (P = 0.805), smoking (P = 0.722), diagnosis (P = 0.758), surgical level (P = 0.760), blood loss (P = 0.172), operative time (P = 0.236), or follow-up (P = 0.372). Serum C-reactive protein level and erythrocyte sedimentation rate in the MCs-1 and MCs-2 groups were significantly higher than those in the MCs-0 group on the third and seventh days (P < 0.05). Postoperative radiographic parameters were significantly higher than preoperative parameters in all 3 groups (P < 0.05). Visual analog scale scores for low back pain in the MCs-0 and MCs-2 groups were significantly different from those in the MCs-1 group (P < 0.05). However, there were no significant between-group differences with respect to Oswestry Disability Index scores or visual analog scale scores for leg pain. CONCLUSION: In this study, Modic changes had no impact on fusion rates and clinical outcomes of transforaminal lumbar interbody fusion with hybrid graft (autologous local bone graft plus allogeneic freeze-dried bone graft). However, MCs-1 increased the risk of cage subsidence and showed superior outcomes in terms of visual analog scale scores for low back pain.