Objectives: The cricothyroid muscle (CTM) has a separate innervation from that of intrinsic laryngeal muscles; therefore, its action may contribute to airflow resistance in children with laryngeal paralysis (LP) secondary to recurrent laryngeal nerve (RLN) palsy. We proposed removal of the CTM as a means of indirectly widening the paralyzed neonatal glottis.
Methods: A prospective study was conducted using a piglet animal model to simulate LP and evaluate the proposed treatment's outcome. LP was induced via bilateral RLN sectioning in seven piglets. The CTMs were then removed. Animals acted as their own controls. Outcome measures consisted of serial inspiratory and expiratory airflow resistance measurements taken (1) with no intervention, (2) after RLN sectioning, and (3) after CTM removal. Several animals were awakened to assess their clinical responses to the interventions. The paired Student's t-test was used for statistical analysis.
Results: Inspiratory airflow resistance was significantly increased by RLN sectioning (p = .0062) and then significantly decreased after subsequent CTM removal (p = .0005). Clinical responses to the interventions mirrored the measured findings.
Conclusions: Removal of the CTM significantly decreases inspiratory airway resistance in piglets with induced LP. This proposed surgical therapy for pediatric bilateral LP warrants further investigation.