Correlation of Clinical and Radiological Outcome After Anterior Cervical Discectomy and Fusion With a Polyetheretherketone Cage

BACKGROUND: data on the impact of ACDF on the cervical kinematics and its association with patient-reported clinical outcomes. The purpose of this study was to investigate the impact of altered cervical sagittal alignment (cervical lordosis) and sagittal range of motion (ROM) on patients' self-reported pain and functional disability, after ACDF with a PEEK cage. METHODS: We prospectively studied 74 patients, who underwent single-, or consecutive two-level ACDF with a PEEK interbody cage. The clinical outcomes were assessed by using the pain numeric rating scale (NRS) and the neck disability index (NDI). Radiological outcomes included cervical lordosis and C2-C7 sagittal ROM. The outcome measures were collected preoperatively, at the day of patients' hospital discharge, and also at 6 and 12 months postoperatively. RESULTS: There was a statistically significant reduction of the NRS and NDI scores postoperatively at each time point (P < 0.005). Cervical lordosis and also ROM significantly reduced until the last follow-up (P < 0.005). There was significant positive correlation between NRS and NDI preoperatively, as well as at 6 and 12 months postoperatively (P < 0.005). In regard to the ROM and the NDI scores, there was no correlation preoperatively (P = 0.199) or postoperatively (6 months, P = 0.322; 12 months, P = 0.476). Additionally, there was no preoperative (P = 0.134) or postoperative (6 months, P = 0.772; 12 months, P = 0.335) correlation between the NDI scores and cervical lordosis. CONCLUSIONS: In our study, reduction of cervical lordosis and sagittal ROM did not appear to significantly influence on patients' self-reported disability. Such findings further highlight the greater role of pain level over the mechanical limitations of ACDF with a PEEK cage on patients' own perceived recovery.