A Correlation Analysis Between Postoperative Dysphagia and Change of C2-C7 Angle after Anterior Cervical Spine Surgery

Abstract

Background. Dysphagia after cervical spinal surgery is one of highly prevalent comorbidities in clinical practice. Studies suggest that excessive O-C2 angle change at occipital-cervical fusion causes the oropharyngeal volume reduction leading to severe dysphagia and even respiratory distress after operation. However, rare study has accessed the impact of C2-C7 angle change on the occurrence of dysphagia after anterior cervical spinal surgery. Methods. From June 2007 to May 2010, A total of 198 patients was treated with anterior cervical decompression and plate fixation and 12 months follow-up was completed in 172 patients. Within the same session, a total of 154 patients underwent anterior cervical disc replacement and at least 1-year follow-up was completed in 98 patients. All 270 patients who participated in this study completed a questionnaire (Bazaz dysphagia questionnaire) after telephone follow-up including the onset and time of appearance of dysphagia, symptom relief, treatment plan and so on. To determine whether excessive cervical lordosis change (change of C2-C7 angle) and other risk factors were associated with the dysphagia symptom, all patients were divided into the dysphagia group and the control group, followed over 12 months.Results. The results showed that 12.8% presented with postoperative dysphagia in anterior cervical discectomy and fusion (ACDF) group and 5.1% in cervical disc replacement (CDR) group. According to the regression equation, the excessive change of C2-C7 angle can significantly increase the incidence rate of postoperative dysphagia. The incidence rate of postoperative dysphagia in patients whose C2-C7 angle change more than 5 degree was significantly greater than patients less than 5 degree. Sex, age, BMI, operation time, blood loss, surgery approach (anterior/posterior), revision ratio, the number of surgical segments, the highest surgical segment, and C3 segment included or not cannot affect the occurrence of dysphagia. Conclusions. Dysphagia after cervical spinal surgery is one of highly prevalent comorbidities. Cervical lordosis change is an important influencing factor on the occurrence of dysphagia after anterior cervical spine surgery.