The three pharyngeal constrictors overlap like nested plant pots to form the posterior and lateral pharyngeal wall. Their sequential superior-to-inferior contraction during the pharyngeal phase of swallowing propels the food bolus from the oropharynx into the oesophagus in less than one second. Weakness from any cause produces pharyngeal dysphagia with pooling of secretions in the piriform sinuses and aspiration risk.
| Origin | Pterygoid hamulus, pterygomandibular raphe, mandible, and tongue; Greater and lesser horns of the hyoid and stylohyoid ligament; Oblique line of the thyroid cartilage and cricoid cartilage |
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| Insertion | Pharyngeal raphe on the posterior pharyngeal wall — all three constrictors overlap in a nested arrangement |
| Nerve Supply | Pharyngeal plexus (CN IX and X) with CN XI accessory fibres |
| Blood Supply | Ascending pharyngeal and facial arteries |
| Actions | Sequential contraction of superior to inferior produces the pharyngeal peristaltic wave that propels the food bolus into the oesophagus; Closes the pharyngeal cavity during swallowing to prevent nasopharyngeal regurgitation |
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The inferior constrictor's thyropharyngeal part produces the Killian dehiscence, a natural weakness between its two parts where Zenker diverticulum herniates posteriorly from increased swallowing pressure against a poorly relaxing cricopharyngeus.
Pharyngeal constrictor paralysis from vagus nerve injury, brainstem stroke, or motor neurone disease produces pharyngeal dysphagia identified by videofluoroscopy as pharyngeal residue and aspiration. Zenker diverticulum is a pulsion diverticulum through Killian's dehiscence between the thyropharyngeus and cricopharyngeus parts of the inferior constrictor, producing regurgitation of undigested food and halitosis managed endoscopically or surgically.
The pharyngeal constrictors are not accessible to external palpation but are assessed functionally by laryngoscopy and videofluoroscopic swallow study.
Constrictor paralysis from neurological injury producing pharyngeal pooling and aspiration risk, managed with modified diet, swallowing rehabilitation, and nasogastric or gastrostomy feeding when severe.
Pulsion diverticulum through Killian's dehiscence between the inferior constrictor parts producing regurgitation and food-smell breath, managed with endoscopic or open cricopharyngeal myotomy and diverticular excision.
