Postoperative Segmental Motion up to 1 Year Following Single-Level Anterior Cervical Discectomy and Fusion: Plate versus Non-plate

STUDY DESIGN: Retrospective observational study. PURPOSE: This study aimed to investigate the impact of plating on postoperative serial segmental motion and its correlation with clinical outcomes in single-level anterior cervical discectomy and fusion (ACDF) for up to 1 year. OVERVIEW OF LITERATURE: The advantages and disadvantages of using cervical plating in ACDF have been well discussed; however, few studies compared the early serial segmental motions at the postoperative level between plating and non-plating. METHODS: In retrospectively collected data, 149 patients who underwent single-level ACDF for degenerative disease were enrolled and divided into non-plating (n=66) and plating (n=83). Interspinous motion (ISM) at the arthrodesis segment, Numeric Rating Scale (NRS) for neck pain, and Neck Disability Index (NDI) were serially evaluated at 3, 6, and 12 months postoperatively. Predictable factors for fusion, including age, sex, plating, diabetes, smoking, and type of grafts, were investigated, and fusion was defined as ISM <1 mm. RESULTS: In both groups, ISM was the highest at 3 months and gradually decreased thereafter, and the plating group showed significantly lower serial ISM than the non-plating group at 12 months. The plating group had lower NRS and NDI scores than the non-plating group at 12 months, and the difference in the NRS scores was statistically significant, particularly at 3 and 6 months, although that of the NDI scores was not. In a multivariate analysis, plating was the most powerful predictor for fusion. CONCLUSIONS: Plating significantly decreases the serial ISM compared with non-plating in single-level ACDF, and such decreased motion is correlated with decreased neck pain until 12 months postoperatively, particularly at 3 and 6 months. Given that plating was the most predictive factor for fusion, we recommend plating even in single-level ACDF for better early clinical outcomes.