Head and neck Flashcards
What are the main features of the neck?
- hyoid bone
- cricoid cartilage
- thyroid cartilage
- lower border of mandible
- cricothyroid membrane
- sternocleidomastoid
- tracheal rings
What are the skeletal components of the neck?
- cervical vertebrae
- mandible
- hyoid bone
- thyroid cartilage
- cricoid cartilage
- tracheal rings
Which cervical vertebrae are important for attachment and rotation of the skull?
C1 and C2
What does C1 do?
articulates with occipital condyles on base of skull to allow nodding motion
What is the other name of C1?
atlas
What is the other name of C2?
axis
How is a shaking head motion acheived?
The atlas articulates with the axis to allow rotation
What are the triangles of the neck?
the topographic areas of the neck bounded by the neck muscles
What are the two major triangles of the neck?
the anterior triangle and posterior triangle
What divides the neck into the anterior and posterior triangles?
The sternocleidomastoid muscle
Where does the sternocleidomastoid muscle originate?
the upper edge of the sternum and the clavicle
What does the sternocledomastoid muscle do?
- when one side contracts, it tilts the head to the same side and turns the face to the opposite side
- when R and L contract together they pull the head forwards
What CN supplies the sternocleidomastoid and trapezius?
the spinal accessory nerve - CNX1
What are the main structures in the anterior triangle of the neck?
- suprahyoid muscles
- infrahyoid muscle
- carotid sheath
What do the suprahyoid muscles do?
- attach hyoid to mandible
- imp for moving the hyoid bone in speech and swallowing
What does the infrahyoid muscle do?
attaches hyoid bone to sternum, thyroid cartilage, and scapula
What does the carotid sheath do?
contains the major arteries to the head and brain
What does the carotid sheath surround?
- common carotid artery
- internal carotid artery
- internal jugular vein
- vagus nerve
What are the main structures of the posterior triangle of the neck?
- external jugular vein
- spinal accessory nerve
- clusters of lymph nodes running along the jugular vein
Which is the main artery supplying the neck?
external carotid
Where does the superior thyroid artery arise from?
the external carotid
What does the superior thyroid artery supply?
part of the thyroid gland and part of the larynx
Where do the inferior thyroid arteries arise?
branch off the subclavian and travel up to the thyroid
What do the internal jugular veins do?
drain venous blood from the brain
Where are the internal jugular veins?
Formed at base of skull and run alongside the internal and common carotid arteries
What do the external jugular veins do?
drain venous blood from the superficial face and scalp
What are the features of the thyroid gland?
- R and L lobes connected by isthmus
- starts superiorly at the lateral edge of the thyroid cartilage and ends superiorly at the 4th or 5th tracheal rings
- very rich blood supply
- posterior border has parathyroid glands
What is a cricothyrotomy?
a procedure to establish an emergency airway
How is a cricothyrotomy done?
- incision made through skin
- cricothyroid membrane is located
- small midline incision made in membrane
- tracheostomy tube inserted
What is a tracheostomy?
a surgical operation to keep the airway open where a tube is inserted directly into the trachea
What are the points of noticeable surface anatomy of the face?
- frontal bone
- orbit
- nasal bones and cartilages
- zygomatic bone
- maxilla
- mandible
How many bones make up the cranium?
22
How many bones make up the neurocranium?
8
Which bones make up the neurocranium?
- frontal
- parietal (2)
- temporal (2)
- occipital (1)
Which bones make up the viscerocranium?
- nasal (2)
- lacrimal (2)
- inferior nasal concha (2)
- maxilla (2)
- mandible
- palatine (2)
- zygomatic (2)
- vomer
What are the temperomandibular joints?
- synovial joints
- between the condyle of the mandible and articular surfaces of temporal bones
- all movement in jaw for chewing and speaking
What are the superficial muscles of mastication?
masseter and temporalis
What are the superior muscles of mastication innervated by?
mandibular branches of CNV trigeminal
What is the masseter?
the most powerful muscle of mastication responsible for elevating the mandible
What is the temporalis?
Muscle of mastication located on the side of the skull in the temporal region which assists in elevating and retracting the mandible
