Killian's dehiscence (pharyngeal dimple) is a weak spot between Thyropharyngeus and Cricopharyngeus components of the inferior pharyngeal constrictor, through which pharyngeal pouches (Zenker diverticulum) may herniate. Which two muscle components form this dehiscence?
- A Oblique fibres of thyropharyngeus above and horizontal fibres of cricopharyngeus below ✓
- B Upper and lower fibres of stylopharyngeus
- C Middle and inferior pharyngeal constrictors
- D Superior pharyngeal constrictor and palatopharyngeus
Explanation
Killian's dehiscence is a triangular gap in the posterior wall of the hypopharynx between the obliquely running thyropharyngeus fibres (from the thyroid cartilage) above and the horizontally running cricopharyngeus fibres (the upper oesophageal sphincter) below. This area of muscular weakness is where posterior pharyngeal pulsion diverticula (Zenker's diverticulum) develop due to raised intraluminal pressure. Zenker's diverticulum is technically a false (pulsion) diverticulum containing only mucosa and submucosa. It is the most common pharyngeal pouch and presents with regurgitation of undigested food and halitosis.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
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Written and medically reviewed by the StethoPrep medical team.