Functions of larynx Flashcards
What is the function of the intrinsic muscles of the larynx?
Control laryngeal inlet
What are the intrinsic muscles of the larynx?
Aryepiglottic Thyroepiglottic Posterior cricoarytenoid Lateral cricoarytenoid Interarytenoid Cricothyroid Thryoarytenoid
What are the attachments of aryepiglottic muscle?
From the muscular process of one arytenoid to the apex of the other then to the lateral aspect of the epiglottis
What is the function of posterior cricoarytenoid?
Abduction (opening) of vocal folds
What is the function of lateral Cricoarytenoid?
Adduction (closing of vocal folds)
What is the function of interarytenoids?
Adduction of vocal folds
What are the attachments of interarytenoid muscles?
Muscular process of one to apex of the other
What is the function of criocthyroid?
Contract to lengthen the vocal folds
What is the function of thryoarytenoid?
Contract to shorten coal folds and close vestibule
What is the motor innervation of the laryngeal muscles?
All recurrent laryngeal (branch of X) except cricothryoid which is external laryngeal nerve (branch of X)
What is the sensory innervation of the larynx?
Below focal folds = recurrent laryngeal
Above vocal folds = internal laryngeal
What provides the blood supply to larynx?
Superior and inferior thyroid artery
What provides venous drainage to the larynx?
Laryngeal veins drain into superior and inferior thyroid veins which drain into internal jugular vein which drains into the left brachiocephalic vein
What is the function of the larynx when fully open?
Ventilation
What is the function of the larynx when half open?
Phonation
What is the function fo the larynx when fully closed?
Swallowing, ingestion of forgein bodies
How does phonation occur?
Vocal folds adducted during expiration, this increases pressure, when they open air is released and they close again and cycle repeats
What muscles raise the larynx?
Suprahyoid and infrahyoid muscles and longitudinal muscles of the pharynx
How does the larynx provide protection against ingestion of forgein matter?
Larynx is raised and epiglottis lowers passively, this closes laryngeal inlet, vocal folds adduct
What are the 3 stages swallowing?
Oral (voluntary) stage
Pharyngeal stage
Oesophageal stage
What forms in the oral stage of swallowing?
Bolus forms
When does the cough reflex occur?
Forgein body in supraglottic cavities detected by sensory receptors
What is the cough reflex?
Initial deep inspiration, VF adduct tightly, this increases thoracic pressure by forceful expiration against closed vocal folds, VF open suddenly, forgein body is dislodged.
