Posterior triangle muscles Flashcards Preview

Head and Neck Anatomy > Posterior triangle muscles > Flashcards

Flashcards in Posterior triangle muscles Deck (31)
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1
Q

Platysma is found in the? (origin and insertion)

A

superficial fascia

2
Q

sternocleidomastoid (SCM) origin

A

manubrium and medial clavicle

3
Q

SCM insertion

A

mastoid process and superior nuchal line

4
Q

SCM innervation

A

CN XI aka Spinal accessory nerve

5
Q

SCM action

A
  • acting unilaterally = laterally flexes and rotates

* acting bilaterally= posterior fibers act to extend the neck; anterior fibers act to flex the neck

6
Q

SCM anterior and posterior fibers attach?

A
  • *posterior fibers attach at superior nuchal line and clavicle AND ACT to extend the neck
  • *anterior fibers attach at mastoid process and manubrium AND ACT to flex the neck
7
Q

SCM stands for?

A

sternocleidomastoid muscle

8
Q

trapezius origin

A

external occipital protuberance, nuchal ligament, spinous processes down to T12

9
Q

trapezius insertion

A

lateral 1/3rd of clavicle, acromion, spine of scapula

10
Q

trapezius innervation

A

CN XI aka Spinal accessory nerve

11
Q

trapezius action

A

elevate, depress, and retract scapula; rotate scapula superiorly

12
Q

Semispinalis capitis and Splenius capitis origin

A

upper thoracic and lower cerivical vertebrae

13
Q

Semispinalis capitis and Splenius capitis insertion

A

occipital bone, between nuchal lines to mastoid process

14
Q

Semispinalis capitis and Splenius capitis innervation

A

posterior rami of cervical nerves (Dorsal rami because deep neck)

15
Q

Semispinalis capitis and Splenius capitis action

A
Unilateral = lateral flexion and rotation
bilateral= extension of head
16
Q

What two muscles are innervated by CN XI aka Spinal accessory nerve?

A

trapezius and sternocleidomastoid (SCM)

17
Q

Levator scapulae origin

A

C1-C4 vertebrae

18
Q

Levator scapulae insertion

A

medial border of scapula

19
Q

Levator scapulae innervation

A

C3-C5 nerves

20
Q

Levator scapulae action

A

Elevate scapula

21
Q

Posterior, Middle and Anterior Scalene origin?

A

C2-C7 vertebrae

22
Q

Posterior, Middle and Anterior Scalene insertion?

A

1st and 2nd ribs

23
Q

Posterior, Middle and Anterior Scalene innervation?

A

C3-C6 nerves

24
Q

Posterior, Middle and Anterior Scalene action?

A
Elevate ribs (inspiration)
*scalene muscles are accessory muscles to the diaphragm because they help to elevate the ribs, which increase the volume in the thoracic cavity
25
Q

Inferior belly of omohyoid origin

A

superior scapula

26
Q

Inferior belly of omohyoid insertion

A

hyoid bone via intermediate tendon

27
Q

Inferior belly of omohyoid innervation

A

ansa cervicalis (part of cervical plexus)

28
Q

Inferior belly of omohyoid action

A

depresses larynx (phonation and swallowing)

29
Q

What triangle is the superior and inferior belly of omohyoid found?

A
inferior= posterior
superior= anterior
30
Q

Platysma innervation?

A

facial nerve

31
Q

Platysma action?

A

tenses skin of neck