Unit I Sensory Innervation of the Head and Neck Flashcards
What is another name for facial nerve paralysis?
Bell’s Palsy
What cranial nerve is the motor innervation to the muscles of facial expression?
VII (Facial)
What cranial nerve is the sensory innervation to the face?
V (Trigeminal)
What are the three branches of the trigeminal nerve?
Ophthalmic, maxillary, and mandibular
What does the opthalmic branch of C.N. V innervate?
Face and scalp
What does the maxillary branch of C.N. V innervate?
Cheek and area lateral to the orbit
What does the mandibular branch of C.N. V innervate?
Chin and temporal region
What are the branches of the ophthalmic nerve?
Supraorbital, supratrochlear, external nasal, infratrochlear, and lacrimal nerves
What are the two smaller branches of the maxillary nerve?
Zygomaticotemporal and zygomaticofacial nerves
What is the most frequently injured nerve with blows to the face (boxers)?
Infraorbital nerve
The infraorbital nerve is a branch of what larger nerve?
Maxillary nerve
What are the three branches of the mandibular nerve?
Auriculotemporal, buccal, and mental nerves
Which branch of the mandibular nerve is the largest?
Auriculotemporal nerve
What is trigeminal neuralgia?
A condition characterized by sudden attacks of severe pain occurring in an area of sensory distribution of the trigeminal nerve
What usually triggers the pain felt with trigeminal neuralgia?
Touch
What is the cause of trigeminal neuralgia?
Unknown
Where does trigeminal neuralgia typically occur neurologically?
Maxillary division (infraorbital nerve)
Where is the second most common neurological location for trigeminal neuralgia?
Mandibular division
What is the sensory innervation of the posterior aspect of the neck and scalp?
Posterior dorsal primary rami of cervical nerves 2-4
How far does the spinal trigeminal nucleus extend down?
C4
What is the innervation for the occipital region of the head?
Greater occipital nerve (posterior primary ramus of C2)
What is the innervation for the upper part of the back of the neck?
Third occipital nerve (posterior primary ramus of C3)
What is the innervation for the lower part of the back of the neck?
Posterior primary ramus of C4
Which cervical nerve has no posterior root carrying sensory fibers and is strictly a motor nerve?
C1
What makes up the cervical plexus?
Anterior primary rami of C1-C4
What is the sensory innervation of the anterior and lateral aspect of the neck?
Anterior ventral primary rami of cervical nerves 2 to 4
Which cervical nerves supply sensory innervation to the skin of the upper limb?
C5-C8
What is the innervation of the lateral part of the occipital region, posterior to the ear?
Lesser occipital nerve (C2)
What is the innervation for the angle of the mandible and the area inferior to the ear?
Great auricular nerve (C2, C3)
Which nerve accompanies the external jugular vein in its path?
Great auricular nerve
What is the innervation for the anterior surface of the neck (the throat)?
Transverse cervical nerve (C2, C3)
What is the innervation for the lateral surface of the neck?
Supraclavicular nerve (C3, C4)
What are the three subdivisions of the supraclavicular nerve?
Medial, intermediate, and lateral supraclavicular nerves
To which muscles does the cervical plexus carry out motor fibers?
Infrahyoid (strap) muscles
What spinal nerves are associates with the ansa cervicalis?
C1-C3
From where does the superior root of the ansa cervicalis descend from?
Hypoglossal nerve
What cervical nerves make up the superior root of the ansa cervicalis?
C1 alone or C1 and C2
From where does the inferior root of the ansa cervicalis descend from?
Cervical nerve branches
Which infrahyoid muscles are innervated by the ansa cervicalis?
Sternohyoid, sternothyroid, and omohyoid
What is the innervation for the thyrohyoid muscle?
Hypoglossal nerve (C1 fibers)
What extra nerve is considered to be a part of the cervical plexus but does nothing for the neck?
Phrenic nerve
From which cervical nerves does the phrenic nerve originate?
C3-C5 (mostly C4)
The phrenic nerve is motor to what?
Diaphragm
The phrenic nerve is sensory to what?
Some of the membranes of the thorax and abdomen
Where is the phrenic nerve located?
Lying on the anterior surface of the anterior scalene muscle running vertically down into the thorax
What is the origin of the platysma?
Superficial fascia over the pectoralis major and deltoid muscles
What is the insertion of the platysma?
Lower border of the mandible and the angle of the mouth
What is the innervation of the platysma?
Cervical branch of facial nerve (C.N. VII)
What is the function of the platysma?
Depresses the mandible and draws down the corner of the mouth
What is the origin of the SCM?
Sternal head from the front of the manubrium, clavicular head from the medial third of the clavicle
What is the insertion of the SCM?
Lateral surface of mastoid process, lateral half of the superior nuchal line
What is the innervation of the SCM?
Accessory nerve (CN XI)
What is the function of the SCM?
Chief flexor of the head
What is a lay term for torticollis?
Wryneck
What is torticollis?
Pathological contraction of SCM
Is torticollis usually bilateral or unilateral?
Unilateral (head tilted toward and the face turned away from the affected side)
Which form of torticollis results from a fibrous tissue tumor which develops at or shortly before birth?
Congenital
Which form of torticollis is due to birth injury?
Muscular
Which form of torticollis occurs in adults and is due to abnormal tonicity (often responds well to chiropractic care)?
Spasmodic
What is the origin of the trapezius?
External occipital protuberance, ligamentum nuchae, and the spinous processes of the seventh cervical and all thoracic vertebrae (all midline)
What is the insertion of the trapezius?
The lateral third of the clavicle, spine of the scapula, and the acromion process (all lateral)
What is the innervation of the trapezius?
Accessory nerve (C.N. XI) and C3 and C4 from the cervical plexus
What is the function of the trapezius?
The upper portion elevates, the middle portion retracts, and the lower portion depresses the scapula
The trapezius also functions in relation with muscles involved with the humerus and scapula exhibiting what type of rhythm?
Scapulohumeral
What vein drains the face and scalp while also containing a large amount of cerebral blood?
External jugular vein
The external jugular vein is formed by the joining of which two veins?
Retromandibular and posterior auricular
Where can the external jugular vein be found?
Running downward and backward along the lateral surface of the SCM and empties into the subclavian vein
What are the six tributaries of the external jugular vein?
Retromandibular, posterior auricular, posterior external jugular, anterior jugular, transverse cervical, and suprascapular veins
During what pathology does the external jugular vein become prominent?
Congestive heart failure or obstruction of the superior vena cava
During what non-pathologic situation is the external jugular vein prominent?
Common among opera singers and bagpipe players due to increased intrathoracic pressure during singing or playing
What specifically can be found along the external jugular vein superficial to the SCM (clinical note)?
Lymph nodes
