Anat 1- Neck Flashcards
What is the origin and distribution of the cervical plexus?
The cervical plexus originates from the ventral rami of spinal nerves C1-C4. It innervates the muscles and skin of the neck. Dermatomes include C2-C4 for sensory distribution.
Where would you inject anesthetic to produce numbness over the front and side of the neck?
Anesthetic should be injected near the cervical plexus, particularly around the nerve roots from C2-C4, to anesthetize the relevant dermatomes for surgical procedures.
What is the innervation and function of the sternocleidomastoid muscle?
The sternocleidomastoid is innervated by the accessory nerve (cranial nerve XI) and cervical nerves (C2-C3). It functions to rotate the head to the opposite side and flex the neck.
What is the effect of a short sternocleidomastoid muscle?
A short sternocleidomastoid may cause torticollis (wry neck), leading to abnormal head positioning due to muscular tightness.
What are the major structures deep to the sternocleidomastoid?
Major structures deep to the sternocleidomastoid include the carotid artery, jugular vein, vagus nerve, and portions of the brachial plexus.
What structures are located between the skin and the trachea during a tracheostomy?
The skin, platysma, anterior jugular veins, thyroid isthmus, and pretracheal fascia lie anterior to the trachea.
What are the major relations of the thyroid gland?
The thyroid gland is located anteriorly to the trachea and is related to the recurrent laryngeal nerve, carotid sheath, and parathyroid glands.
What nerves must be protected when tying off blood vessels during thyroid surgery?
The recurrent laryngeal nerves and external branch of the superior laryngeal nerves should be carefully preserved during thyroid surgery.
What is the carotid sheath, and what are its contents?
The carotid sheath is a fascial structure containing the common and internal carotid arteries, internal jugular vein, and vagus nerve.
What are the major branches and distribution of the subclavian artery?
The subclavian artery gives rise to the vertebral artery, internal thoracic artery, and thyrocervical trunk, supplying the brain, neck, and upper chest.
What happens in subclavian steal syndrome?
Subclavian steal syndrome occurs when the subclavian artery is obstructed, causing reversed blood flow in the vertebral artery to compensate, potentially leading to dizziness or arm ischemia.
What structures define the boundaries of the neck?
The suprasternal notch, clavicles, acromion process, spine of the scapula, mental prominence, lower border and angle of the mandible, mastoid process, superior nuchal line, and external occipital prominence.
Where is the hyoid bone located, and what is its level relative to the cervical vertebrae?
The hyoid bone is located at the level of C3 on the cervical vertebrae.
Where are the thyroid and cricoid cartilages located in relation to cervical vertebrae?
The thyroid cartilage is located at the level of C4-C5, and the cricoid cartilage is at C6.
What are the major parts of the first rib?
The first rib has two surfaces, a head, neck, scalene tubercle, and grooves for the subclavian artery and vein.
What vein runs superficially to the sternocleidomastoid muscle?
The external jugular vein (EJV).
What branches of the cervical plexus are located in the posterior triangle of the neck?
The great auricular nerve, lesser occipital nerve, transverse cervical nerve, and supraclavicular nerves.
What is the function and location of the sympathetic trunk in the neck?
The sympathetic trunk lies along the vertebral column and is responsible for sympathetic innervation to structures in the head, neck, and thorax.
