Midterm Flashcards
1
Q
Collum is also known as?
A
“coller” or neck
2
Q
Nuchae is also known as?
A
Nape or posterior neck
3
Q
Cervix is also known as?
A
Neck
4
Q
Another name for “Adam’s Apple”
A
Laryngeal prominence
5
Q
What vertebral level is the Thyroid cartilage found?
A
C4- C5 vertebral level
6
Q
What is the function of the hyoid bone?
A
Site of attachment for many anterior neck muscles and some muscles of the tongue
7
Q
Parts of the hyoid bone
A
Body,
Greater and Lesser Cornus (horns)
8
Q
What vertebral level is the hyoid bone found?
A
C3`
9
Q
How many cricoid cartilage are there?
A
one
10
Q
Is the cricoid cartilage a part of the trachea?
A
No, it is a cartilage of the larynx
11
Q
What vertebral level is the cricoid cartilage found?
A
C6
12
Q
Where does the tracheal cartilage begin?
A
Below C6, inferior to the cricoid cartilage
13
Q
The Chin is also known as?
A
Mentum
14
Q
What muscle covers the Ramus of the Mandible?
A
Masseter
15
Q
What is the mastoid process a part of?
A
Temporal Bone
16
Q
What is the skin of the neck innervated by?
A
Primarily C2,3 &4 spinal nerves
17
Q
What are dermatomes?
A
Area of skin innervated by a specific nerve segment
18
Q
What nerve innervates the anterior 2/3 of the head (face)?
A
Trigeminal Nerve or V nerve
19
Q
Does the Trigeminal Nerve innervate the angle of mandible?
A
No, C2 innervates the angle of mandible
20
Q
What part of the head does C2 spinal nerve innervate?
A
Occiput, majority of ear, angle of mandible and under the chin/jawline (refer to image for C2, C3 and C4 dermatomes)
21
Q
What is the Origin of the platysma muscle?
A
Fascia and skin of deltoid & pectoral regions
22
Q
What is the insertion of the platysma muscle?
A
Mandible and tissues around the mouth
23
Q
What is the innervation of the platysma muscle?
A
Facial nerve (cervical branch), VII Nerve
24
Q
What are the actions of the Platysma muscle?
A
1) helps to depress the mandible
2) tighten and wrinkle the skin of antero-lateral neck
3) depresses the lower lip and angle of the mouth
25
What does the external jugular vein usually come from?
Posterior auricular vein and retromandibular veins
26
Where does the external jugular vein usually travel?
Superficial to the Sternocleidomastoid muscle and deep to the clavicle
27
Where can the facial vein drain into?
One, two of all of the following:
1) external jugular vein
2) anterior jugular vein
3) internal jugular vein
28
What are the borders of the anterior triangle of the neck?
Posterior - SCM
Superior - Inferior border of the mandible
Anterior - midline of anterior neck
29
What are the borders of the posterior triangle?
Inferior - clavicle
Anterior SCM
Posterior Trapezius
30
What is is the Origin of Sternocleidomastoid muscle?
Sternum (tendinous)
| Clavicle
31
What is is the insertion of Sternocleidomastoid muscle?
Mastoid process
| Occiput
32
What is is the innervation of Sternocleidomastoid muscle?
Spinal Accessory nerve (XI nerve) for motor innervation
| C2 (sometimes 3) for sensory innervation used for nociception and proprioception
33
What is is the action of Sternocleidomastoid muscle?
```
Unilateral = ipsilateral (same side) flexion and contralateral (opposite side) rotation of head and neck
Bilaterial = flexion of neck and extension of head
```
34
What are the borders of the submandibular triangle
Posterior - posterior belly of Digastric muscle
Anterior - anterior belly of diastric
Superior - body of mandible
35
What are the borders of the submental triangle
Inferior - hyoid bone
| Superior - Anterior bellies of left and right dygastric muscles
36
What are the borders of the carotid triangle?
Superior - posterior belly of digastric muscle
Posterior - SCM
Inferior - Superior belly of omohyoid muscle
37
What are the borders of the muscular triangle triangle
Superior - superior belly of omohyoid muscle
Posterior - SCM
Anterior - anterior midline of neck
38
What are the borders of the supraclavicular triangle
Superior- belly omohyoid
Inferior - clavicle
Anterior - SCM
39
What are the borders of the occipital triangle
Posterior - Trapezius
Anterior - SCM
Inferior - Inferior belly of omohyoid muscle
40
What are the contents of the submandibular triangle
```
submandibular glands (salivary gland)
Facial artery and vein
```
41
What are the contents of the carotid triangle
Carotid sheath and its contents:
1) common carotid artery and carotid bifurcation (internal and external carotids)
2) internal jugular vein
3) X nerve, vagus nerve
42
What are the contents of the muscular triangle
Infrahyoid muscles
Thyroid gland
Larynx (largeal cartilages) and tracheal cartilages
43
What are the contents of the supraclavicul triangle
Sublavian artery and vein
Elements of the brachial plexus
Scalene muscles
Phrenic nerve
44
What are the contents of the occipital triangle
```
XI nerve (spinal accessory)
Several cutaneous nerves from the cervical plexus
```
45
What forms spinal nerves form the cervical plexus?
ventral rami C1-C4
46
What are the five types of branches contributing to the cervical plexus?
```
Cutaneous branches
Communicating or hitchhiker branches
Ansa Cervicalis nerve
Phrenic Nerve
Motor branches (to muscle of deep anterior neck
```
47
Along the posterior border of what muscle do the 4 main terminal cutaneous branches exit?
SCM
48
What are the 4 main terminnal cutaneous branches?
Lesser occipital nerve
Great Auricular nerve
Transverse Cervical nerve (transverse coli nerve)
Supraclavicular nerve
49
What is the nerve innervation of the lesser occipital nerve?
Ventral ramii C2 fibers
50
What does the lesser occipital nerve innervate
Skin of posterior scalp behind the ear
51
What is the nerve innervation of the great auricular nerve?
Ventral ramii of C2, C3
52
What does the great auricular nerve innervate
Sensory innervation to skin below and anterior to external ear and part of ear
53
What is the nerve innervation of the transverse cervical nerve?
Ventral ramii of C2, C3
54
What does the transverse cervical nerve innervate
most skin of the anterior neck
| terminal branches penetrate the platysma muscle
55
What is the nerve innervation of the supraclavicular nerve?
Ventral ramii of C3, C4
56
What does the supraclavicular nerves innervate
```
innervates skin of base of neck, upper thorax and top of the shoulder
contains three branches:
1)medial
2) intermediate
3) lateral
```
57
What are communicating or hitchhiking branches?
Join with nerves en route to their destinations,
| but are not really part of those nerves
58
What Cervical fibers join the spinal accessory nerve?
C2, C3, & C4
59
What do C2, C3 & C4 provide sensory innervation to?
SCM (C2, C3) and Trapezius C3, C4
60
What nerve fiber joins with the hypoglossal nerve?
C1
61
What muscles do C1 fibers supply motor innervation to?
Geniohyoid muscle
| Thyrohoid muscle
62
What is ansa cervicalis?
A nerve loop
63
What is the Ansa Cervicalis comprised from?
Ventral ramii of C1-3
64
What does the Ansa Cervicalis supply?
all the infrahyoid muscles except the thyrohyoid muscle
65
What nerve root does the Superior root of Ansa Cervicalis contain?
C1
66
What cranial nerve does C1 hitchhike with?
cranial nerve XII
67
What is another name for Superior Root of Ansa Cervicalis?
Descending hypoglossal ramus of Ansa Cervicalis
68
What nerve root does the inferior ramus of Ansa Cervicalis contain?
C2-C3
69
What is another name for Inferior Ramus of Ansa Cervicalis?
Descending cervical ramus of Ansa Cervicalis
70
Which muscles do the two roots of the ansa cervicalis supply?
Omohyoid muscle, Sternohyoid & Sternothyroid muscles
71
What nerve roots does the Phrenic nerve contain?
C3-5
72
What does the Phrenic nerve supply?
Motor and sensory to the diaphragm
73
What is the appearance of the infrahyoid muscles?
Broad, flat muscles
74
What is the function of the infrahyoid muscles?
Swallowing and speech either to mover or stabilize the hyoid bone or thyroid cartilage
75
What is the origin of the sternohyoid muscles?
Manubrium
76
What is the origin of the sternothyroid muscles?
Manubrium
77
What is the origin of the inferior belly of the omohyoid muscle?
Scapula (superior border)
78
What is the origin of the superior belly of the omohyoid muscle?
Tendinous sling from the clavicle
79
What is the origin of the thyrohyoid muscles?
Thyroid Cartilage
80
What is the insertion of the sternohyoid muscles?
Body of hyoid
81
What is the insertion of the Sternothyroid muscles?
Thyroid cartilage
82
What is the insertion of the inferior belly of omohyoid muscle?
Tendinous sling on clavicle
83
What is the insertion of the superior belly of omohyoid muscle?
Body of hyoid
84
What is the insertion of the thyrohyoid muscles?
Greater Cornu of hyoid
85
What is the action of the sternohyoid muscles?
Depresses hyoid
86
What is the action of the sternothyroid muscles?
Depresses thyroid cart
87
What is the action of the Inferior belly of the omohyoid muscle?
Depresses hyoid or stabalize position
88
What is the action of the thyrohyoid muscle?
Depresses hyoid
| Elevates thyroid Cartilage
89
What is the innervation of the sternohyoid muscle?
Ansa Cervicalis (C1-C3)
90
What is the innervation of the sternothyroid muscle?
Ansa Cervicalis (C1-C3)
91
What is the innervation of the Inferior and Superior bellies of omohyoid muscles?
Ansa Cervicalis (C1-C3)
92
What is the innervation of the thyrohyoid muscle?
C1 that hitchhikes with XII nerve
93
Do the digastric muscles derive from the same innervations?
No, the anterior and posterior bellies have different embryonic origins
94
What is the location of the stylohyoid muscle?
Parallel to the posterior belly of the digastric muscle
| The tendon of insertion usually splits and passes on either side of the intermediate tendon of the digastric muscle
95
What is the location of the mylohyoid muscle?
Within the submental triangle
| Helps form the floor of the oral cavity
96
What is the location of the geniohyoid muscle?
superior to the mylohyoid muscle
97
What is the origin of the anterior belly of the digastric muscles?
Inner mandible (near symphysis)
98
What is the origin of the posterior belly of the digastric muscles?
Mastoid process
99
What is the origin of the stylohyoid muscles?
Styloid process part of the temporal bone
100
What is the origin of the mylohyoid muscle?
Body of mandible (inner surface)
101
What is the origin of the geniohyoid muscle?
Inner mandible (near symphysis menti)
102
What is the insertion of the anterior belly of the digastric muscle?
Intermediate tendon held by tendinous sling to hyoid
103
What is the insertion of the posterior belly of the digastric muscle?
Intermediate tendon held by tendinous sling to hyoid
104
What is the insertion of the stylohyoid muscles?
Hyoid
105
What is the insertion of the mylohyoid muscle?
Median raphe (seam) and hyoid
106
What is the insertion of the geniohyoid muscle?
Hyoid
107
What is the action of the anterior belly of the digastric muscle?
Protracts, retracts, & elevates hyoid; assists to depress mandible
108
What is the action of the posterior belly of the digastric muscle?
Protracts, retracts, & elevates hyoid; assists to depress mandible
109
What is the action of the stylohyoid muscle?
Elevates and retracts hyoid
110
What is the action of the mylohyoid muscle?
Elevates hyoid and floor of oral cavity
111
What is the action of the geniohyoid muscle?
Elevates and protracts hyoid
112
What is the innervation of the anterior belly of the digastric muscle?
Trigeminal (V) nerve
113
What is the innervation of the posterior belly of the digastric muscle?
Facial (VII) nerve
114
What is the innervation of the stylohyoid muscle?
Fascial (VII) nerve
115
What is the innervation of the mylohyoid muscle?
Trigeminal (V) nerve
116
What is the innervation of the geniohyoid muscle?
C1 (via XII)
117
What is the origins of anterior, middle, posterior scalenes and scaleneous minimis?
TPs of cervical
118
What are the insertion of the anterior, middle, and the scaleneous minimis?
First rib
119
What is the insertion of the posterior scalene muscle?
Second rib
120
What are the actions of the anterior, middle, and the scaleneous minimis?
Elevates first rib; Ipsilateral flexion of neck
121
What is the actions of the posterior scalene muscle?
Elevates second rib; Ipsilateral flexion of neck
122
What is the innervation of anterior, middle, posterior and the scaleneous minimis?
Lower cervical ventral rarnii
123
What are the borders of the scalene triangle?
Inferiorly: first rib
Anteriorly: anterior scalene
Posterior: middle scalene
124
What exits the neck en route to the extremities through the scalene triangles
```
Subclavian artery (subclavian vein enters neck neck anterior to the anterior scalene)
Roots of the brachial plexus - inclues ventral rami of C5 - T1
```
125
Clinical significance of the scalene triangle?
Brachial plexus and or the subclavian artery are subject to possible compression at this location: if this happens then this could lead to neuro-vascular problems of upper extremity
126
What is the origin of Longus Colli?
T.P.'s and bodies
127
What is the origin of Longus Capitis?
T.P's
128
What is the origin of Rectus Capitis Anterior?
T.P of C1 and Lateral Mass of C1
129
What is the origin of Rectus Capitis Lateralis?
T.P.
130
What is the insertion of Longus Colli?
T.P.'s and bodies
131
What is the insertion of Longus capitis?
Occiput (Basilar Portion)
132
What is the insertion of Rectus Capitis Anterior?
Occiput (basilar portion)
133
What is the insertion of Rectus Capitis Lateralis?
Occiput (jugular process)
134
What is the action of Longus Colli?
Flex and rotate neck
135
What is the action of Longus Capitis?
Flexion of head
136
What is the action of Rectus capitis Anterior?
Flexion of head
137
What is the action of Rectus Capitis Lateralis?
Ipsilateral flexion of head
138
What is the innervation of Longus Colli, Longus capitis, Rectus Capitis anterior, & Rectus Capitis Lateralis?
Cervical ventral Rami
139
What fascial layer provides attachments of clavicle, hyoid, occiput, mandible, s.p's of cervical vertebrae, ligamentum nuchae, and surround the trapezius and SCM?
superificial layer
140
What fascial layer defines the visceral compartment in the neck and surrounds the thyroid gland, trachea, esophagus, larynx, pharynx and infrahyoid muscles?
Pretracheal layer
141
What does the prevertebral layer of the deep fascia of the neck do?
Surrounds the cervical spine and deep muscles of the posterior neck. Also surrounds the deep muscles of the anterior neck (ie prevertebral muscles)
142
How many of the deep fascial layers form the carotid sheath?
three
143
What does the carotid sheath contain?
Common Carotid artery (and bifurcation)
Internal Jugular Vein
Vagus (X) nerve
Ansa Cervicalis
144
What is the clinical significance of the facial layers of the neck?
The interfascial planes (potential spcaes between fascial layers such as the retropharyngeal space) and extend logitudinally through the neck. Therefore, tumors/infection can potentially spread along these planes longitudinally through the neck (thoracic cavity -> neck -> base of the skull)
145
Where does the right common carotid originates from?
Brachiocephalic Artery
146
Where does the left common carotid originate from?
Aortic Arch
147
Where do the common carotids bifurcate?
Superior to the thyroid cartilage
148
What does the common carotid bifurcate into?
Internal and external carotid arteries
149
What is the dilation in are at the bifurcation of the common carotid artery into vertebral level C3 and C4?
Carotid sinus
150
What kind of receptor is the carotid sinus?
Mechanoreceptor (baroreceptor) which is a sensory receptor
151
What does the Carotid Sinus respond to and how?
Responds to blood pressure
Increases in blood pressure, increases the rate of nerve impulses which can result in vasodilation and decreased heart rate -> decreased blood pressure
152
What is the innervation of the carotid sinus?
sinus branch of the glossopharyngeal (IX) nerve and some X nerve innervation
153
What is the caroid sinus reflex?
Increases in blood pressure result in stimulation of the carotid sinus -> stimulation of the IX nerve -> CNS -> vasodilation, decreased heart rate and eventually decreased blood pressure
154
What does the carotid sinus respond to?
Any changes in pressure such as externally pressing on the sinus
a) inappropriate changes in cardiovascular function
b) activation of carotid sinus reflex
155
Where is the carotid body located?
Behind the carotid bifurcation
156
What does the carotid body consist of?
Specialized receptor cels, rich plexus of nerve endings and rich capillary bed
157
What is the receptor that the carotid body contains?
Chemoreceptor to monitor blood chemistry changes
| O2 and CO2
158
Where does the carotid artery go from and to?
from the carotid bifurcation and it travels deep and superiorly to the base of the skull
159
What does the internal carotid artery enter the skull from?
The carotid canal and distributes to the brain (much of the brain) and eyeball and other orbital structures
160
How many branches come off of the external carotid artery?
eight
161
What are the eight major branches of the external carotid artery?
```
Superior Thyroid Artery
Ascending Pharyngeal Artery
Lingual Artery
Facial Artery
Occipital Artery
Posterior Auricular Artery
Maxillary Artery
Superficial Temporal Artery
```
162
What does Superior thyroid artery give off?
Usually gives off a superior laryngeal artery
163
What does superior thyroid artery supply?
Supplies (including its branches) blood to thyroid, larynx, infrahyoid muscles and parts of the SCM
164
What does the ascending pharyngeal artery supply?
Supplies pharyngeal wall
165
Where does the lingual artery travel?
branch of external carotid near the posterior belly of digastric muscle, travels deep to it to the hypoglossus
166
What does the lingual artery supply?
Supplies tongue and floor of oral cavity
167
Where does the facial artery travel?
Travels through the submandibular triangle and crosses over onto the face at about the mid-body of the mandible
It transverses across the superficial face, paralleling the facial vein, and terminates at the medial angle of the eye
168
What does the facial artery supply?
submandibular gland
anterior face, up to the orbit
Superior and inferior lip (labia)
169
Does the facial artery supply the upper or lower teeth?
No
170
Where does the occipital artery travel?
Travels posterior to the external ear, parallels the greater occipital nerve and supplies the posterior scalp
171
Where does the posterior auricular artery travel and supply?
Travels behind the ear and supplies parts of the external ear and some of the skin behind the ear
172
what are the terminal branches of the external carotid artery?
Maxillary artery
| Superficial temperal artery
173
Where does the maxillary artery travel ?
travels deep to the mandible into the infratemporal fossa
174
Where does the maxillary artery arise from?
Deep to the mandible
175
Where does the maxillary artery send branches to?
Lower teeth and mandible
Maxilla and some of the upper jaw teeth
Muscles of mastication
Dura mater around the brain
176
Where is the superficial temporal artery located and supply?
Palpable above the TMJ in front of the ear and supplies much of the superficial structures of the parieto-temporal region of the head
177
What does the right subclavian branch from?
the brachiocephalic artery
178
What does the left subclavian branch from?
Aortic arch
179
What are the four major branches of the subclavian artery?
Internal Thoracic Artery
Vertebral Artery
Thyrocervical Trunk
Costocervical Trunk
180
Where does the internal thoracic artery travel?
Descends into the thorax along the internal surface of the thoracic wall
181
What does internal thoracic artery supply?
Supplies the anterior wall of the thorax and breast
182
Where does the vertebral artery travel?
Ascends and enters a transverse foramen at C6
183
Where does the vertebral artery send branches to?
Deep neck structures, spinal nerves and the spinal chord. Ultimately it becomes one of the major arteries to the brain
184
What are the 4 branches of the thyrocervical trunk?
Inferior thyroid artery
Ascending cervical artery
Transverse cervical artery
Suprascapular artery
185
What does the inferior thyroid artery supply?
Helps to supply thyroid gland, esophagus, larynx and trachea
186
What does the ascending cervical artery travel and supply?
Travels along the anterior scalene and transverse processes
| Supplies structures in the deep cervical region
187
What does the transverse cervical artery branch into?
Superficial transverse cervical artery
| Deep transverse cervical artery
188
What is another name for the deep transverse cervical artery?
Dorsal scapular artery
189
What does the superficial transverse cervical artery supply?
Trapezius muscles
190
What does the deep transverse cervical artery supply?
Rhomboid major, minor and levator scapula muscles
191
What does the suprascapular artery supply?
Supraspinatus and infraspinatus muscles
192
What two branches does the costocervical trunk split into?
Deep cervical branch and superior intercostal branch
193
What does the deep cervical branch supply?
Deep posterior neck structures
194
What does the superior intercostal branch supply?
Supply superior parts of the thorax
195
What are dural venus sinuses?
Venous sinuses within cranial dura mater and drain blood from the brain
196
Where does the internal jugular vein travel?
Begins at the jugular foramen (from the major sinus in the brain)
Travels inferiorly through the neck and receives tributaries from facial, lingual, thyroid and pharyngeal veins
197
What does the internal jugular vein form?
The internal jugular vein joins with the subclavian vein to form the brachiocephalic vein
198
Is the internal jugular vein a major vein?
Yes, it is the major vein that drains blood from the brain
199
Where does the vertebral veins travel?
Begin in the suboccipital triangle region
| It parallels the vertebral arteries
200
Where does the vertebral veins drain from and to?
Drain deep neck structures and drain into the brachiocephalic veins
201
What is the thyroid gland?
Endocrine (ductless) gland
| Weighs about 30 grams and enlarges during pregnancy
202
Where is the thyroid gland located?
Found at C5, C6 & C7 and straddles the lower larynx and the upper trachea
203
What are the parts of the thyroid gland?
Left and right lobe joined by an isthmus and sometimes a third lobe projecting superiorly from the isthmus along midline called the pyramidal lobe
204
What is the thyroglossal duct?
Marks the path of migration of the thyroid gland from the tongue to it's final position and it usually degenerates in the adult
205
What does the thyroid gland create and secrete?
Thyroxine (increase cellular metabolism)
| Calcitonin (decrease blood calcium)
206
What does the thyroid gland receive blood supply from?
Superior thyroid artery from the external carotid artery
Inferior thyroid artery from the thyrocervical trunk
Thyroideus ima artery (present less than 10%of the time) and a branch of the brachiocephalic artery of the aortic arch
207
What do the thyroid veins (superior, middle and inferior) drain into?
Internal jugular vein
208
What are the parathyroid glands?
```
Endocrine glands (ductless)
Small and ovoid (6 by 3mm)
```
209
What are the four parathyroid glands?
Superior parathyroid glands (Left and Right)
| Inferior parathyroid glands (left and right)
210
Where is are the parathyroid glands located?
Embedded in the posterior aspect of the thyroid gland
211
What do the parathyroid glands synthesize and secrete?
Parathyroid hormone - increases blood calcium through bone breakdown
212
What are the two primary groups of the lymphatics of the neck?
Superficial (cervical group), group of nodes and vessels
| Deep (cervical group), group of nodes and vessels
213
What does the superficial cervical group of lymph nodes drain into?
Generally drains to the deep cervical group
214
Where do the deep cervical group of lymph nodes drain into?
Drains lymph via vessels along the carotid sheath
215
Where are the deep cervical group of lymph nodes located?
Deep to SCM
216
What does the deep cervical group form?
Two jugular lymphatic trunks:
Right trunk drains into the right subclavian vein or right internal jugular vein at base of neck
Left trunk drains into the thoracic duct (the major lymph vessel of the body), which ascends out of the thorax
217
Where does the thoracic duct drain into?
The left internal jugular vein and left subclavian veins
218
What is the skin of the face innervated by?
Branches of the Trigeminal (V) nerve
219
What type of skin is the scalp made of?
Thick and hairy skin
220
What is the glea aponeurotica?
Intermediate tendon (aponeurosis) between the frontalis and occipitalis muscles
221
What are the 5 layers of the scalp?
```
Skin
Connective tissue (subcutaneous tissue)
Aponeurosis
Loose Connective Tissue
Pericranium
```
222
What are the superficial muscles of the face (mimetic muscles or muscles of fascial expression) innervated by?
Fascial nerve (VII)
223
What are the attachments of the frontalis muscle?
Attaches posteriorly to galea aponeurotica
| Anterior attachment to skin at eyebrow
224
What are the attachments of the occipitalis muscle?
Attaches anteriorly to galea aponeurotica
| Posterior attachment to occipital bone
225
What are the action of the epicranius muscles?
Move the scalp, elevate and wrinkle skin of the forehead and elevate the eyebrows
226
What are the epicranius muscle?
Frontalis muscle
| Occipitalis muscle
227
What is the orbicularis oculi muscle?
```
Muscle around the orbit
Made up of 3 portions:
1) orbital portion - around the orbital rim
2) palpebral portion - eyelids
3) lacrimal portion
```
228
What is the action of orbicularis oculi muscle?
Sphincter muscle that allows closure or tightening of the eye. Therefore it is the blink muscle
229
What is the orbicularis oris?
muscles located around the mouth
230
What is the action of the orbicularis oris?
Sphincter like action that allows to close lip/purse your lips. Important in speech and mastication (chewing)
231
What is the risorius muscle?
Smiling muscle and originates from the fascia of the cheek and inserts into the corner of the mouth
232
What is the action of risorius?
Retract the angle of the mouth
233
What is the insertion of the zygomaticus major muscle?
Inserts into the angle of the mouth
234
What is the action of the zygomaticus major muscle?
elevates the angle of the mouth
235
What is the zygomaticus minor muscle insertion?
Inserts into upper lip
236
What is the action of the zygomaticus min muscle?
Elevates the upper lip
237
What is the action of depressor anguli oris?
Depresses the angle of the mouth
238
What is the location and action of depressor labii oris?
More medial than depressor anguli oris
| Action - depresses lower lip
239
What is the action of the buccinator?
Deep to buccal fat pad and muscle of the cheek
| Action - compresses the cheek against the teeth and gums
240
What is the action of the mentalis muscle?
Action - depresses lower lip along midline
| Pouting muscle
