Comparative Study Between the Cervical Cage with Screws and the Classical Cage in Anterior Cervical Discectomy and Fusion

Abstract

Background: Anterior cervical discectomy and fusion (ACDF) remains the gold-standard surgical treatment for cervical disc disease (CDD). Stand-alone zero-profile (Zero-P) cages with integrated screws provide low-profile fixation, potentially reducing complications such as implant subsidence compared to traditional cages. However, comparative data on clinical and radiological outcomes between these cage types remain limited, particularly in short- and intermediate-term follow-up systems. Methods: This prospective randomized study evaluated 50 patients with single- or double-level CDD undergoing ACDF, comparing outcomes between the stand-alone Zero-P device (n = 25) and a traditional cage (n = 25). Clinical assessments were conducted at 1, 6, and 12 months postoperatively, including neck and arm pain severity (visual analog scale, VAS), functional disability (neck disability index, NDI), neurological status (ASIA impairment scale), dysphagia (Bazaz score), fusion rates (assessed via dynamic radiographs and CT scans), and cervical sagittal alignment (Cobb angle measurements). Results: The stand-alone Zero-P group exhibited superior early and intermediate outcomes, including significantly reduced neck pain at 1 month (VAS: 3.52 vs. 4.48, p = 0.004), greater functional improvement at 12 months (NDI: 4.80 vs. 8.68, p < 0.001), and better neurological recovery (ASIA grade improvement: 4.58 vs. 3.64, p < 0.001). Radiologically, stand-alone Zero-P demonstrated higher fusion rates at 6 months (88% vs. 56%, p = 0.025) and improved early cervical alignment (1-month Cobb angle: 14.36° vs. 11.36°, p < 0.001). Final fusion rates at 12 months were comparable (96% vs. 84%, p = 0.349), which suggested no long-term disadvantage. Conclusion: The Zero-P device provides significant early and intermediate-term advantages over traditional cages in ACDF, including pain relief, functional restoration, and cervical alignment, without compromising long-term fusion success. These findings support its consideration as a preferred option for single or double-level ACDF.