Advanced Infrahyoid Muscles Quiz

Q1. Why can injury to the ansa cervicalis weaken several infrahyoid muscles while sparing thyrohyoid?

• Thyrohyoid has no motor innervation
• Thyrohyoid is supplied by the facial nerve
• Thyrohyoid is supplied by the recurrent laryngeal nerve
• Thyrohyoid receives C1 fibers outside the ansa cervicalis loop

Q2. Why is sternothyroid unable to depress the hyoid directly?

• It attaches to the thyroid cartilage rather than the hyoid
• It has no attachment to the sternum
• It inserts on the mandible
• It is a suprahyoid muscle

Q3. How can sternothyroid and thyrohyoid act sequentially on the laryngeal framework?

• Both muscles only rotate the head
• Both muscles act exclusively on the tongue
• They can move the thyroid cartilage relative to the sternum and hyoid in complementary directions
• They form a sphincter around the trachea

Q4. Why is the omohyoid an important surgical landmark in the neck?

• It encloses the internal carotid artery
• It passes through the jugular foramen
• It forms the entire floor of the mouth
• Its course helps define cervical triangles and orient regional anatomy

Q5. What is the functional importance of stabilizing the hyoid bone?

• It provides a stable base for muscles acting on the tongue, floor of mouth, and mandible
• It fixes the cervical vertebrae together
• It closes the carotid arteries
• It prevents all laryngeal movement

Q6. Why may C1 fibers associated with the hypoglossal nerve be mistaken for fibers originating from CN XII?

• The hypoglossal nerve is a branch of the cervical plexus
• They hitchhike along CN XII before leaving it for cervical targets
• C1 and CN XII share the same motor nucleus
• CN XII originates from the C1 spinal cord

Q7. Which infrahyoid relationship is most relevant when approaching the thyroid gland from the anterior neck?

• Thyrohyoid surrounds the carotid bifurcation
• Sternohyoid and sternothyroid overlie the thyroid region
• All infrahyoid muscles lie posterior to the vertebral column
• Omohyoid lies inside the thyroid capsule

Q8. Why can the term strap muscles include more than one anatomical layer?

• The group contains superficial and deep muscles despite their shared strap-like organization
• All four muscles occupy exactly the same fascial plane
• The term refers only to sternohyoid
• The muscles are layers of one continuous muscle

Q9. Which action would be most impaired if sternohyoid, sternothyroid, and omohyoid were all denervated?

• Depression and stabilization of the hyoid-laryngeal complex
• Abduction of the vocal folds
• Elevation of the soft palate
• Protraction of the mandible

Q10. Which statement best integrates infrahyoid muscle anatomy?

• They are layered anterior neck muscles that coordinate hyoid and laryngeal movement through cervical motor innervation
• They are pharyngeal constrictors supplied entirely by the vagus nerve
• They are posterior neck extensors supplied by dorsal rami
• They are muscles of mastication supplied by the mandibular nerve