Anatomy Of Head And Neck Flashcards
Surface anatomy of the neck
Tracheal rings reinforced with incomplete/rings of cartilage to keep the trachea open
Skeletal components of neck
Larynx reinforced by cartilage
Cervical vertebrae
4th cervical
-holes in transverse foramina
-spinous process is bifib
What is different about the structure of c1 and c2
Different because structure relates to function
Atlas (C1): Articulate with occipital condyles on base of skull (nod “yes”)
Axis (C2): The atlas articulates with the axis and allows rotation (shake head “no”)
Dens is to stop anterior displacement of the axis
Triangles of the neck
Posterior neck triangle
Describe the accessory nerve
-cranial nerve no.11 (CN XI)
-Is a motor nerve
-Supplies sternocleidomastoid and trapezius
-Clinical test for function: turn head and shrug shoulders against resistance
Anterior triangle
-trachea
-larynx
-pharynx
Arterial supply for the neck
Arterial supply (oxygenated blood which comes from the heart)
Subclavian and common carotid branch directly from the aorta
Venous drainage of the neck
Deoxygenated blood which returns to the heart
External jugular vein runs over the top of sternocleidomastoid
Internal jugular vein runs beneath the sternocleidomastoid
What structures are within the Carotid sheath
Internal jugular vein
Common carotid artery
Vagus nerve (CN X)
Thyroid gland
Describe the procedure to establish an emergency airway
Cricothyrotomy is a procedure to establish an emergency airway
1. An incision is made through the skin and the cricothyroid membrane is located
2. A small midline incision is made in the membrane and the tracheostomy tube is inserted.
3. A tracheostomy is a surgical operation to keep the airway open. A tube is inserted directly into the trachea.
Surface anatomy
Cheekbone: zygoma and zygomatic arch
Eye socket: orbit
Maxilla houses the upper teeth
Mandible houses the lower teeth
Bones of the skull
Connections between the bones of the skull is called sutures (stitch together after birth allows compression of head during natural childbirth)
Bones of the skull (tmj)
What are the (superficial) muscles of mastication needed for
For chewing when eating
Temporalis: when anterior muscles contract, mandible is pulled up
When posterior muscles contract, mandible pulled down
Muscles of facial expression
Orbicularis oculi (muscle around the eyes)
Orbicularis oris (muscle around the lips)
Zygomaticus: attaches to corner of mouth, contracts muscles for a smile
Describe the branches of the facial nerve
Cranial nerve no.7 (CN VII) - The facial nerve divides into 5 divisions in the parotid gland
Temporal, Zygomatic, Buccal, Manibular and Cervical
The branches are purely motor, very small and very superficial
They are easily damaged as a result of facial trauma, facial surgery
How to test the function of the facial nerve
Function can be tested by asking patient to make exaggerated facial expressions
Effect of Botox on facial nerve
Botox blocks neurotransmission in the facial nerve, preventing the muscles of facial expression from creasing the skin
Name the 3 main branches of the trigeminal nerve
Has three main branches:
ophthalmic (sensory)
maxillary (sensory)
mandibular (sensory and motor to muscles of mastication)
Skin innervation of the trigeminal nerves
The same division supplies the deeper structures.
test for function of trigeminal nerve
Functional test:
-For sensory innervation, sharp-blunt test over all divisions
-For motor innervation, ask patient to protrude lower jaw. If mandibular motor fibres have been damaged the jaw will deviate to the injured side
