Posterior and Anterior Triangles of the Neck

Question 1

Platysma

Answer 1

O:  Infraclavicular and supraclavicular regions
I:  1.  Base of Mandible
    2.  Orbicularis Oris
    3.  Skin of Cheek
    4.  Skin of Lower Lip
N:  Facial
A:  1.  Tenses skin of neck
     2.  Draws corners of mouth inferiorly
     3.  Assist in depressing mandible

Question 2

Sternocleidomastoid

Answer 2

O: 1. Lateral surface of mastoid process of temporal bone
2. Lateral half of Superior Nuchal Line
I: Sternal: Anterior surface of manubrium of sternum
Clavicular: Superior surface of medial 1/3 of clavicle
N: Spinal Accessory Nerve C3, C4
A: Unilateral: Tilts head to same side (Laterally flexes head) and rotates it so face is turned superiorly to opposite side
Bilateral: Extends neck at Atlanto-Occipital joints. Flexes cervical vertebrae so chin approches manubrium, extends superior cervical vertebrae while flexing inferior vertebrae so chin is thurst forward with head kept level
With Cervical Vertebrae Fixed: May elevate manubrium and medial ends of clavicles, assisting pump-handle action of deep respiration

Question 3

Trapezius

Answer 3

O:  1. Medial 1/3 of superior nuchal line
      2.  External occipital protuberance
      3.  Nuchal Ligament
      4.  Spinous Processes of C7-T12
I:  1. Lateral 1/3 of clave le
    2.  Acromion
    3.  Spine of scapula
N:  Spinal Accessory Nerve C3, C4
A:  1.  Descending part elevates
     2.  Ascending part depresses
     3.  Middle part retracts scapula
     4.  Descending and ascending parts act together to rotate glenoid cavity superiorly

Question 4

Splenius Capitus

Answer 4

Caudal: Cervical and Upper Thoracic Spinous Processes
Rostral: 1. Superior nuchal line
2. Mastoid Process
N: Cervical DPR
A: Extension and ipsilateral rotation of head and neck

Question 5

Levator Scapulae

Answer 5

O: Posterior Tubercles of transverse processes of C1-C4 vertebrae
I: Medial border of scapula inferior to root of scapular spine
N: Dorsal Scapular Nerve C3, C4
A: 1. Elevate scapula
2. Rotate glenoid cavity inferiorly by rotating scapula

Question 6

Scalenus Anterior

Answer 6

O: Transverse processes of C3-C6 vertebrae
I: 1st Rib
N: Cervical VPR
A: 1. Forward flexion of neck
2. Elevates 1st rib during forced inspiration

Question 7

Scalenus Medius

Answer 7

O: Posterior tubercles of transverse processes of C5-C7
I: 1. Superior surface of 1st rib
2. Posterior to groove for subclavian artery
N: Cervical VPR
A: 1. Flex neck laterally
2. Elevates 1st rib during forced inspiration

Question 8

Scalenus Posterior

Answer 8

O: Posterior Tubercles of transverse processes of C5-C7
I: External border of 2nd rib
N: Cervical VPR
A: 1. Flex neck laterally
2. Elevate 2nd rib during forced inspiration

Question 9

Omohyoid

Answer 9

N: Ansa cervicalis
A: (as an infrahyoid muscle) Fixate/depress hyoid and thyroid cartilage