Long-term clinical and radiological outcomes following anterior cervical discectomy and fusion by zero-profile anchored cage

OBJECTIVES: The purpose of this study was to extend the results of our previous study providing a minimum of 4-year follow-up results of a prospective study following implantation of a cervical cage with an integrated fixation system. SUMMARY OF BACKGROUND DATA: The use of cervical intersomatic cages with an integrated fixation system for anterior cervical discectomy and fusion (ACDF) has increased rapidly in this last decade. In addition to immediate stabilization, these implants allow avoidance of anterior plating and iliac crest bone-grafting. METHODS: Patients were studied prospectively, and data were collected and analyzed. Intersomatic cages with an integrated fixation system were used in consecutive 100 patients operated on for ACDF. Intraoperative parameters, clinical, and outcome scores were recorded. Radiographs were taken to evaluate implant positioning and fusion rate, disc height (DH), and changes in adjacent disc spaces. All the patients had a minimum 4-year follow-up. RESULTS: A total of 127 cages were implanted in the 100 patients. Compared to preoperatively, the visual analog scale, 36-item short-form health survey, the Japanese Orthopedic Association, and the Neck Disability Index scores were significantly improved at 1-year follow-up without change during subsequent follow-up. At 4 years, the fusion rate was 97%. Two patients complained about minor dysphagia-related symptoms, which resolved rapidly. DH index and cervical Cobb angle were significantly restored after surgery, and the results were maintained during the whole follow-up. CONCLUSIONS: This is a prospective, independently conducted study on cages with an integrated fixation system with 4-year long follow-up. Findings of this study seem to be interesting regarding outcomes and low complications rates compared to recent series using other implants with integrated fixation system. Larger, randomized controlled trials are warranted.