Cricoid Cartilage

cartilago cricoidea

The cricoid cartilage is the only complete cartilaginous ring of the airway, forming the inferior laryngeal framework. It has a narrow anterior arch and a wider posterior lamina (Killian's pout) that bears facets for the arytenoid cartilages superiorly and for the inferior thyroid horns at the cricothyroid joints laterally. The first tracheal ring lies immediately below it. The cricoid defines the subglottic space inferiorly.

Region: Neck

Clinical Relevance

Clinical Notes

The cricoid is the narrowest part of the paediatric airway (at the subglottic level within the cricoid ring) and the determinant of paediatric endotracheal tube size (uncuffed tubes used to avoid mucosal pressure necrosis within the inelastic cartilage ring). In adults, cuffed tubes are used as the glottis is the narrowest point. Cricoid pressure (Sellick manoeuvre) is applied by compressing the cricoid arch to occlude the oesophagus during rapid sequence induction. Subglottic stenosis develops from prolonged intubation irritating the subglottic mucosa adjacent to the cricoid.

Pathology

Common Injuries & Conditions

Subglottic Stenosis from Prolonged Intubation

Prolonged endotracheal intubation causes mucosal ischaemia at the subglottic level where the tube cuff presses against the cricoid inner surface, producing circumferential scar contracture within the rigid cartilage ring causing airway narrowing presenting as exertional dyspnoea and stridor weeks to months after extubation.