Function of the upper esophageal sphincter during swallowing: the
grabbing effect.
Pouderoux, Philippe, & Peter J. Kahrilas.
Department of Medicine, Northwestern University Medical School,
Chicago, Illinois 60611
APStracts 3:0264G, 1996.
This study investigated deglutitive axial force developed within the
pharynx, upper esophageal sphincter (UES), and cervical esophagus.
Position and deglutitive excursion of the UES were determined using
combined manometry and videofluoroscopy in 8 healthy volunteers.
Deglutitive clearing force was quantified with a force transducer to
which Nylon balls of 6 or 8 mm diameter were tethered and positioned
within the oropharynx, hypopharynx, UES, and the cervical esophagus.
Axial force recordings were synchronized with videofluoroscopic
imaging. Clearing force was dependent upon both sphere diameter
(p<0.05) and location with greater force exhibited in the
hypopharynx and UES compared to the oropharynx and esophagus
(p<0.05). Within the UES, the onset of traction force
coincided with passage of the pharyngeal clearing wave but persisted
well beyond this. On videofluoroscopy, the persistent force was
associated with the aboral motion of the ball caught within the UES.
Force abated with gradual slippage of the UES around the ball. The
force attributable to the combination of UES contraction and
laryngeal descent was named the grabbing effect. The grabbing effect
functions to transfer luminal contents distal to the laryngeal inlet
at the end of the pharyngeal swallow, presumably acting to prevent
regurgitation and/ or aspiration of swallowed material.
Received 6 June 1996; accepted in final form 13 November 1996.
APS Manuscript Number G228-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996