Posterior Triangle Flashcards
(98 cards)
What forms the apex, anterior, posterior, and inferior borders of the posterior ∆?
Apex:
Occipital Bone
Anterior:
SCM
Posterior:
Trapezius
Inferior:
Clavicle (Middle 1/3)
What forms the roof of the posterior ∆?
Roof:
Investing Fascia
What fascial layers form the floor of the posterior ∆?
- Underlying muscles from superior to inferior
Floor Fascia:
- Prevertebral Fascia
Floor Muscles:
- Splenius Capitis
- Levator Scapulae
- Posterior, middle, and Anterior Scalene muscles
T or F: the scalene muscles are secondary muscles of respiration.
True
What is the origin and insertion of Splenius Capitis?
Origin:
- Lower half of ligamentum nuchae
- Spinous processes of vertebrae C7-T4
Insertion:
- Mastoid Process
- Skull below lateral one-third of superior nuchal line
What is the innervation and action of splenius capitis?
Innervation:
Posterior Rami of Middle Cervical Nerves
Action:
- Together: draw head backward
- Indiviual: Rotate head to one side (turn face to same side)
What is the origin and insertion of anterior scalene?
Origin:
Transverse processes of Cervical Vertebrae (like all the scalenes)
Insertion:
1st Rib
What is the action and innervation of the anterior scalene?
Innervation:
- Ventral Rami of the Cervical Plexus (like all of the scalenes)
Action:
- Laterally Bends the Neck
- Elevates the 1st Rib
What is origin and insertion of the middle scalene?
Origin:
Transverse Processes of Cervical Vertebrae (like all of the scalenes)
Insertion:
1st Rib
What is the action and innervation of the middle scalene?
Innervation:
- Ventral Rami of the cervical plexus (like all of the scales)
Action:
- Laterally Bends the Neck
- Elevates the 1st Rib
What is the origin and insertion of the posterior scalene?
Origin:
- Transverse Processes of the Cervical Vertebrae (like all of the scalenes)
Insertion:
- 2nd Rib
What is the action and innervation of the posterior scalene?
Innervation:
- Ventral Rami of the cervical plexus (like all of the scales)
Action:
- Laterally bends the Neck
- Elevates the 2nd rib
What is the origin and insertion of levator Scapulae?
Origin:
-C1-C4 transverse Processes
Insertion:
- Medial Border of the Scapula (above the spine)
Innervation and action of levator scapulae?
Innervation:
Dorsal Scapular n.
Action:
Moves the shoulder girdle
What is the common innervation of all scalene muscles?
- Ventral Rami of the Cervical Plexus
What muscle crosses the inferior border of the posterior ∆ crossing anterior to middle scalene?
- Inferior Belly of Omohyoid
What are the borders of the scalene ∆?
Anterior:
Anterior Scalene
Posterior:
Middle Scalene
Inferior:
Rib 1
What structures pass through the scalene ∆?
- Subclavian Artery
2. ROOTS and TRUNKS of the Brachial Plexus pass to upper limb
T or F: the Phenic nerve and Subclavian Vein pass though the scalene ∆.
FALSE, these DO NOT
What nerve roots give rise to the phrenic Nerve?
C3, C4, C5
C4 being the biggest contributor
What muscles does the phenic nerve emerge from behind then subsequently travel along?
Anterior Scalene
T or F: the subclavian artery provides an important source of oxygenated blood to the thyroid and brain.
True
What defines the 3 parts of the subclavian a?
- How many branches off of each part?
Anterior Scalene Parts: 1. Medial to Scalene (3) 2. Posterior to Scalene (1) 3. Lateral to Scalene (1)
What artery arises from the 3rd part of the subclavian?
Dorsal Scapular a. (to the rhomboids)