An Enlarged Superior Horn of Thyroid Cartilage Presenting During Intubation: A Case Report

Variations in laryngeal anatomy, particularly of the superior horn of the thyroid cartilage (SHTC), can pose challenges in airway management. While minor anatomic differences are commonly encountered, clinical encounters of SHTC variants are rarely documented. We present a case of an asymptomatic SHTC variant identified during routine intubation, the first documented with high-definition video.

A 55-year-old male presented for a sacroiliac fusion operation. He reported a prior intubation during which clinicians noted an abnormal laryngeal structure. Preoperatively, he denied dysphagia, phonation changes, or respiratory symptoms, though he did describe intermittent throat "tightness." Intubation was performed with video laryngoscopy, which revealed a prominent SHTC without impediment to endotracheal tube placement. The procedure and extubation were uneventful. Postoperative review of prior imaging demonstrated the variant anatomy on a cervical CT scan obtained 23 years earlier, predating anterior cervical fusion surgery, and on a lateral cervical radiograph from 4 years prior.

SHTC variants are uncommon and often asymptomatic, though patients may report foreign body sensation, odynophagia, or neck discomfort. They are often associated with prior neck trauma, and age-related ossification increases fracture risk. Literature documents occasional airway management complications, including failed laryngeal mask airway placement. Consideration of anatomic variants should be in the differential diagnosis, as they may support avoidance of supraglottic airway devices in these patients. Management ranges from observation to specialist referral for symptomatic or severe cases.

Anomalous SHTC morphology is a rare finding with implications for airway management. Clinicians should include thyroid cartilage variants in the differential diagnosis of patients with unexplained throat symptoms and remain vigilant during intubation. Further research is warranted to better define the prevalence, clinical impact, and management strategies for atypical thyroid cartilage anatomy.