Is the Anatomical Protrusion on the Posterior Hypopharyngeal Wall Associated with Cadavers of Only the Elderly?

Abstract

Cricopharyngeal bars are commonly seen on a barium swallow radiologic examination and represent the failure of the cricopharyngeus to relax. Traditionally, the bars have been considered as functional or physiologic protrusions. Recently, anatomical cricopharyngeal protrusion has been found in about 30% of cadavers of the elderly, suggesting that such a structural change may become a physical barrier that affects the normal deglutition in a living person. This suggests that such a radiographic finding should be carefully considered when interpreting radiologic and manometrical examinations and managing dysphagia of the elderly. However, the finding of the anatomical cricopharyngeal protrusion was based on the observation of cadavers of the elderly (mean age = 77 years). The aim of this study was to further investigate whether such an anatomical cricopharyngeal protrusion exists in cadavers of other ages. Using the dissection method, we examined 63 human cadavers that were divided into three age groups: young adult (6 females and 10 males, age = 16-24 years old), adult (8 females and 23 males, age = 25-64 years old), and early elderly (5 females and 11 males, age = 65-69 years old). We found that 57 of the 63 cadavers had a smooth mucosal surface on the posterior hypopharyngeal and upper esophageal wall. A slightly thickened posterior muscular wall was observed at the cricoid level in six cadavers (five from the adult group and one from the early elderly group), but its boundary was not clearly identified. Taking the previous reports together, our results suggest that an anatomical cricopharyngeal protrusion is closely associated with the aging process.

Morphometric and anthropometric analysis of Killian's triangle

“…In this study we investigated the variability in the macroscopic morphology of this muscle, and found that in about one third of the examined cases the muscle showed a deformation that was causing a constriction or recess on the pharyngoesophageal transition. These findings seem to agree with those of other studies about the structural changes of the CPM in the elderly cadaver,15, 16 and suggest that the consequent protrusion in the pharyngeal lumen in the living person may become a physical barrier affecting normal swallowing and causing increased intrabolus pressures. The cricopharyngeal protrusion can appear as a cricopharyngeal bar on the lateral radiographs of barium swallows.…”

Effect of cricopharyngeus muscle surgery on the pharynx

“…These findings need to be considered in light of previous findings of nonobstructive and obstructive bars seen in asymptomatic elderly individuals 3, 19–21. Leonard et al reported asymptomatic CPBs of all sizes in more than 30% of 88 elderly subjects without dysphagia 19.…”