Altered pharyngeal structure and dynamics among patients with cervical kyphosis

Abstract

Objectives/hypothesis: Deformities of the anterior cervical spine are an established cause of dysphagia. Whereas osteophytes and spinal fusion hardware have been reported to alter bolus flow and contribute to swallowing dysfunction, the relationship between abnormal spine curvature and swallowing dysfunction is not established. The purpose of this investigation was to evaluate the association between cervical kyphosis and objective measures of swallowing dysfunction on videofluoroscopy.

Study design: Case-control study of patients presenting to tertiary dysphagia center.

Methods: All videofluoroscopic swallow studies (VFSS) performed at our institution, between August 1, 2014, and August 1, 2015, were retrospectively reviewed to identify patients with abnormal cervical kyphosis, according to Cobb and Jackson angle measurements. Patients with kyphosis were age- and gender-matched to persons without kyphosis. VFSS and demographic parameters were collected and compared between groups.

Results: Thirty-six patients with cervical kyphosis exceeding two standard deviations (SD) beyond established age-specific normal ranges were identified. The mean age of the entire cohort was 61.6 (SD ±19.1) years. Mean pharyngeal area was 3.34 cm² greater in kyphosis patients compared to controls (95% confidence interval [CI]: 0.47-5.21 cm² ; P = .0007). This was associated with increased hypopharyngeal transit time (0.57 seconds, 95% CI: 0.045-1.09 seconds, P = .034), and higher prevalence of penetration (P = .014). There was no significant difference in the pharyngeal constriction ratio (PCR), a surrogate measure of pharyngeal strength (P = .83).

Conclusions: Patients with cervical spine kyphosis have a significantly dilated pharynx (P = .0007), elongated hypopharyngeal transit time (P = .034), and worsened penetration aspiration scores (P = .021). Absence of a difference in PCR suggests adequate compensation as a group.

Level of evidence: 3b. Laryngoscope, 127:1832-1837, 2017.

Keywords: Dysphagia; VFSS; cervical spine; deglutition; dynamic swallow study; kyphosis; laryngology; myelopathy; penetration aspiration scale; pharynx.