Dysphagia Following Cervical Spine Surgery With Anterior Instrumentation Evidence From Fluoroscopic Swallow Studies

Study Design. Retrospective review. Objective. The purpose of this study was to evaluate alterations in objective swallowing parameters in patients reporting dysphagia after anterior cervical-spine surgery. Summary of Background Data. Dysphagia is increasingly recognized as a potential complication of anterior surgical approaches to the cervical spine. Retraction pressure on the esophagus that alters blood flow, edema of the pharynx, and laryngeal nerve injury are among factors implicated. There has been little investigation of the biomechanics of swallowing in a large cohort of patients reporting postoperative dysphagia. Methods. The fluoroscopic swallow studies of all persons reporting dysphagia after anterior c-spine surgery between January 1, 2000, and December 31, 2008, were retrospectively reviewed. The dysphagic cohort was divided into early (<2 months postsurgery) and late (>2 months) groups. Aspiration and completeness of epiglottic inversion were noted. Objective measures of pharyngeal wall thickness, upper esophageal sphincter opening, hyoid displacement, pharyngeal constriction, and pharyngeal transit time were abstracted and compared to the same parameters in age and sex-matched normal control subjects. Analysis of variance was used for statistical comparison of objective measures across groups. Results. Sixty-seven patients were identified. Significant differences were identified between control subjects and both patient groups, as well as between the 2 patient groups, for most objective measures considered. Instances of aspiration were identified in 50% of patients in the early postoperative group, reduced to 18% in the later group. Significantly increased pharyngeal wall thickness and poor epiglottic inversion were characteristic of both c-spine groups. Conclusion. Significant alterations in swallowing mechanics can accompany c-spine surgery with anterior plating. A number of these changes improve over time, leaving patients with relatively minor impairment; however, some appear to be long-lasting. Education and dysphagia therapy can be useful treatment adjuncts.