Extrinsic muscles
Nerve supply: Ansa cervicalis (CN XII + C1, C2, C3)
Infrahyoid muscles (Depressors of larynx):
Mnemonic: TOSS
- Thyrohyoid (Thyroid to hyoid)
- Omohyoid (Suprascapular notch to hyoid)
- Sternohyoid (Sternum to hyoid)
- Sternothyroid (Sternum to thyroid)
Suprahyoid muscles (Elevators of larynx):
Mnemonic: MDGS
- Mylohyoid (Mandible to hyoid)
- Digastric (Mandible and Mastoid to hyoid)
- Geniohyoid (Tongue to hyoid)
- Stylohyoid (Styloid process to hyoid)
Intrinsic muscles
Muscles | Origin | Insertion | Function |
Thyroepiglotticus | Thyroaryetenoid muscle | Epiglottis (lateral surface) | Opens laryngeal inlet |
Aryepiglotticus | Oblique arytenoid muscle | Epiglottis | Closes laryngeal inlet |
Posterior cricoarytenoid | Cricoid (posterior/lamina) | Arytenoid | Abductor of vocal cords |
Lateral cricoarytenoid | Cricoid (lateral/arch) | Arytenoid | Adductor of vocal cords |
Interarytenoid (Transverse and Oblique) | Arytenoid | Arytenoid | Adductor of vocal cords |
Cricothyroid | Cricoid | Thyroid | Tensor of vocal cords |
Thyroarytenoid/Vocalis | Thyroid | Arytenoid (Thyroarytenoid)/Vocal ligament (Vocalis) | Relaxor of vocal cords |
Nerve supply:
Mnemonic: SCAR
1. Superior laryngeal nerve (External laryngeal nerve): Cricothyroid
2. All other muscles: Recurrent laryngeal nerve
well structured.