OBJECTIVES: The pharyngeal and esophageal shortenings during deglutition are attributable to longitudinal muscle contraction. The two shortenings may be independent events because the longitudinal pharyngeal and esophageal muscular insertions are believed to be separated from each other. The aim of this study was to investigate the superior attachments of the longitudinal esophageal muscle. STUDY DESIGN: Prospective. METHODS: With use of dissection, sectional anatomy, and confocal microscopy, 30 adult cadavers were examined in this study. RESULTS: We found that the longitudinal esophageal muscle fibers had multiple superior insertions. Some of the fibers were continuous with the longitudinal pharyngeal muscles and merged with a membrane-like fascia that anchored the pharyngoesophageal wall to the thyroid cartilage. CONCLUSIONS: This study demonstrates that the longitudinal pharyngeal and esophageal muscle fibers are continuous with each other and are integrated with fibrous and cartilaginous structures. Such anatomic integrity at the pharyngoesophageal junction is important for the function of the upper esophageal sphincter.
OBJECTIVES: The pharyngeal and esophageal shortenings during deglutition are attributable to longitudinal muscle contraction. The two shortenings may be independent events because the longitudinal pharyngeal and esophageal muscular insertions are believed to be separated from each other. The aim of this study was to investigate the superior attachments of the longitudinal esophageal muscle. STUDY DESIGN: Prospective. METHODS: With use of dissection, sectional anatomy, and confocal microscopy, 30 adult cadavers were examined in this study. RESULTS: We found that the longitudinal esophageal muscle fibers had multiple superior insertions. Some of the fibers were continuous with the longitudinal pharyngeal muscles and merged with a membrane-like fascia that anchored the pharyngoesophageal wall to the thyroid cartilage. CONCLUSIONS: This study demonstrates that the longitudinal pharyngeal and esophageal muscle fibers are continuous with each other and are integrated with fibrous and cartilaginous structures. Such anatomic integrity at the pharyngoesophageal junction is important for the function of the upper esophageal sphincter.