Influence of Modic Changes on Cage Subsidence and Intervertebral Fusion after Single-Level Anterior Cervical Corpectomy and Fusion

Objectives This retrospective study aimed to determine the impact of Modic changes (MCs) on cage subsidence (CS) and intervertebral fusion after anterior cervical corpectomy and fusion (ACCF). Methods This study enrolled 61 patients with MCs who underwent single-level ACCF between January 2010 and December 2015 at our institution. The control group included 63 age-matched patients without MCs treated during the same period. The results from clinical and radiological assessments were reviewed, and radiographic CS was defined by an intervertebral height at the final follow-up that was less than the postoperative intervertebral height. Results No significant differences in gender, age, operative time, blood loss, or follow-up results were observed between the MCs and control groups. Significantly more patients experienced CS in the MCs group than in the control group (41.0% vs. 15.9%; p = 0.003). The frequencies of CS among patients with type I MCs (40.0%, 8/20) and type II MCs (41.5%, 17/41) were significantly higher than that in the control group (15.9%, 10/63; p < 0.05). Both groups showed significant improvements in clinical assessment scores after surgery and at final follow-up compared with preoperative values (p < 0.05). Conclusion In summary, all 61 patients with MCs who underwent ACCF achieved good fusion results. MCs in the surgical segment had no significant effect on intervertebral fusion, but both type 1 and type 2 MCs may increase the risk of CS.