Superficial Triangles and Cervical Viscera Flashcards
What nerve is associated with the first (mandibular) pharyngeal arch? What muscles are associated with it?
Trigeminal (CN V)
Muscles of mastication Mylohyoid Anterior belly digastric Tensor tympanic Tensor veli palatini
What nerve is associated with the second (hyoid) pharyngeal arch? What muscles are associated with it?
Facial n (CN VII)
Muscles of facial expression
Stapedius
Stylohyoid
Posterior belly digastric
What nerve and muscle are associated with the third pharyngeal arch?
Glossopharyngeal (CN IX)
Stylopharyngeus m.
What nerve is associated with the fourth and sixth pharyngeal arches? What muscles are associated with them?
CN X: Vagus n. (Superior laryngeal branch and recurrent laryngeal branch)
Cricothyroid Levator veli palatini Constrictors of pharynx Intrinsic muscles of larynx Striated mm of esophagus
What skeletal structures are associated with the fourth and sixth arches?
Thyroid cartilage Cricoid cartilage Arytenoid cartilage Corniculate cartilage Cuneiform cartilage
Meckel’s cartilage leads to development of what head/neck structure?
Mandible
[also contributes to alisphenoid, malleus, and incus]
Development of the hyoid involves what 2 arches?
Arches II and III
The larynx is derived from what pharyngeal arch?
4th arch
What muscles are supplied by the spinal accessory n. (CN XI)?
Sternocleidomastoid m.
Trapezius m.
Borders of posterior triangle of the neck
Posterior: trapezius m.
Anterior: SCM m.
Inferior: middle 1/3 of clavicle
Roof = investing fascia Floor = prevertebral fascia
Borders of anterior triangle of the neck
Superior: inferior border of the mandible
Lateral: anterior border of SCM m.
Medial: sagittal line down the midline of the neck
Roof = investing fascia Floor = visceral fascia
What fossa is present in the anterior cervical triangle?
Lesser supraclavicular fossa
What fossa is present in the posterior cervical triangle?
Greater supraclavicular fossa
What is the most superficial cutaneous muscle of facial expression?
Platysma m.
What innervates the platysma m.
Cervical branch of facial n.
What happens with unilateral contraction of SCM?
Turns head to opposite side (particularly sternal head of SCM)
T/F: SCM can either flex or extend the head
True — depending on center of rotation it can do either
If center of rotation is anterior to the OA, the SCM extends the head
If center of rotation is posterior to the OA, the SCM flexes the head
What condition is characterized by contracture of the SCM?
Muscular torticollis
What is the most common cause of muscular torticollis
Birth trauma
[can also be muscle or nerve injury later in life]
A benign fibrous tumor may accompany muscular torticollis, called _____ ____
Fibromatosis colli
The complexity of the neck is due in part to the fascial compartments. What are the 5 compartments?
Superficial fascia Investing layer Pretracheal layer Prevertebral layer Alar fascia and carotid sheath
What is the first “deep” fascial layer you encounter in the neck?
Investing layer
In what fascial compartment would you find the platysma m.?
Superficial fascia
In what fascial compartment/layer would you find the deep neck muscles?
Prevertebral layer
In what fascial layer of the neck would you find the esophagus, trachea, thyroid, and strap muscles?
Pretracheal layer
What type of fascia runs between the carotid sheaths?
Alar fascia
What is the function of the carotid sheath?
Surrounds and protects the great vessels and nerves in the neck as the head moves
There are 3 named zones of penetrating trauma. Define the boundaries of zone I and the structures that are included in that zone
Zone I = the horizontal area between the clavicle/suprasternal notch and the cricoid cartilage
Important structures: Thoracic outlet structures Cupola of lung Proximal common carotid a. Vertebral a. Subclavian a. Trachea Esophagus Thoracic duct Thymus
There are 3 named zones of penetrating trauma. Define the boundaries of zone II and the structures that are included in that zone
Zone II = area between the cricoid cartilage and the angle of the mandible
Important structures: Internal carotid a. External carotid a. Jugular vv. Pharynx Larynx Esophagus Recurrent laryngeal n. Spinal cord Trachea Thyroid Parathyroids
There are 3 named zones of penetrating trauma. Define the boundaries of zone III and the structures that are included in that zone
Zone III = area that lies between the angle of the mandible and the base of the skull
Important structures:
Distal extracranial carotid a.
Vertebral a.
Uppermost segments of jugular vv.
What landmark in the posterior cervical triangle exists halfway between the mastoid process and clavicle, serving as the outlet for the cutaneous branches of the cervical plexus?
Erb’s point
T/F: the bulk of nuchal innervation anterolaterally comes from Erbs point
True
What are some of the cutaneous nerves of the neck?
From Erb’s point: Great auricular n. Transverse cervical n. Supraclavicular n. Lesser occipital n.
Others include cutaneous branches of posterior rami C4-8, greater occipital n., and third occipital n.
What are the other 2 names for the transverse cervical a.?
Superficial cervical a. or cervicodorsal a.
[same names apply to corresponding vv.]
What nerve bundle emerges around the scalene musculature in the neck?
Brachial plexus
What is the most superficial vein in the posterior cervical triangle?
External jugular v.
The superficial temporal v. joins the _______ vein to become the ________ vein, which then splits again into anterior and posterior divisions
Maxillary; retromandibular
The superficial temporal v. joins the maxillary vein to become the retromandibular vein, which then splits again into anterior and posterior divisions. The anterior division of the retromandibular v. joins the _____ v., while the posterior division joins the _______ v.
Facial; posterior auricular