Anatomy of the Back - Unit 1 Flashcards
What are the types of ligaments associated with the vertebral column?
- supraspinous
- nuchal
Name the ligaments that connect the tips of spinous processes from C7 to sacrum.
supraspinous ligaments
Name the ligaments that extend from external occipital protuberance and posterior border of foramen magnum to spinous process of cervical vertebrae.
nuchal ligaments
What does the transverse cervical artery supply?
trapezius
What is the origination of the transverse cervical artery?
Thyrocervical Trunk off the subclavian artery
Which nerve travels with the transverse cervical artery?
CN XI
What are the branches of the transverse cervical artery?
- superficial cervical
- dorsal scapular (33% of the time)
What does the dorsal scapular artery supply?
- levator scapula
- Rhomboids
What is the origination of the dorsal scapular artery?
- 33% of the time it is a branch of the transverse cervical a.
- 66% of the time it is a branch of the subclavian a.
What nerve travels with the dorsal scapular artery?
dorsal scapular nerve
What is the origination of the vertebral artery?
subclavian artery
Where does the vertebral artery enter and exit the neck?
- enters at C6 and exits at C1 through transverse foramina
- enters foramen magnum to help form the Circle of Wills
What does the vertebral artery supply?
suboccipital muscles
What does the thoracodorsal artery supply?
latissimus dorsi
What nerve travels with the thoracodorsal artery?
thoracodorsal nerve
Where does the thoracodorsal artery originate?
it is one of two terminal branches of the sub scapular artery which comes off the subclavian
Where does the posterior intercostal artery originate?
descending thoracic aorta
What does the dorsal cutaneous branches of the posterior intercostal artery supply?
deep back muscles
Where does the occipital artery originate?
the external carotid artery
What does the occipital artery supply?
posterior scalp and sub occipital muscles
What does the Dorsal (posterior) rami of the spinal nerve supply?
- intrinsic back muscles
- zygopophyseal joints
- dermatomal cutaneous innervations of the skin
What are then “named” dorsal rami?
- suboccipital nerve
- greater occipital nerve
Where does the sub occipital nerve exit the vertebral column?
between occiput and C1
What does the sub occipital nerve supply?
suboccipital muscles
Where does the greater occipital nerve exit the vertebral column?
between C1 and C2
What is another name for CN XI?
spinal accessory nerve
What does CN XI supply?
trapezius muscle and sternocleidomastoid muscle
Where does the dorsal scapular nerve originate?
ventral (anterior) ramus of C5
Where and with what artery does the dorsal scapular nerve travel?
along the scapula with dorsal scapular artery
Where does the thoracodorsal nerve originate?
posterior cord of brachial plexus (C6-C8)
What does the thoracodorsal nerve supply?
latissimus dorsi
What is the deep fascia of the thoracic and lumbar regions?
thoracolumbar fascia
Describe thoracolumbar fascia
- extends laterally from spinous processes
- forms thin covering intrinsic thoracic back muscles
- forms thick covering over lumbar muscles
- continuous with deep fascia from cranium and pelvis
Major groups of Back Muscles
Extrinsic
Intrinsic
Subdivisions of extrinsic back muscles and how many muscles are in each subdivision.
- superficial, 5
- intermediate, 2
What is the function of the extrinsic back muscles?
produce and control upper limb and respiratory movements
Subdivisions of intrinsic back muscles and how many muscles are in each subdivision.
- superficial,2
- intermediate, 3
- deep, 4
- minor deep, 4
What is the function of the intrinsic back muscles?
produce vertebral movements and maintain posture
What are the 5 superficial extrinsic back muscles?
- trapezius
- latissimus dorsi
- levator scapulae
- rhomboid major
- rhomboid minor
What is the function of the superficial extrinsic back muscles?
- Connect axial skeleton to superior appendicular skeleton
- produce and control upper limb movements
Where do the superficial back muscles receive innervation? What is the exception?
- from the dorsal rami of cervical nerve
- trapezius receives innervation from CN XI
Describe the trapezius size and shape
it is a large muscles with three parts (superior, middle and inferior) that can act independently or together
Where do insertions tend to be located?
more distal
Where do origins tend to be located?
towards the midline
What are the origins of the trapezius?
- medial 1/3 of superior nuchal line
- external occipital protuberance
- nuchal ligament
- spinal processes of C7-T12
What are the insertions of the trapezius?
- lateral 1/3 of clavicle
- acromion
- spine of scapula
What are the actions of the trapezius?
- elevation of the scapula (by inferior trap)
- retraction of scapula (by middle trap)
- depression of scapula (by inferior trap)
- upward rotation (by inferior and superior trap)
What nerves innervated the trapezius?
- CN XI for motor
- C3,C4 for sensory
What artery supplies the trapezius?
transverse cervical
Describe the latissimus dorsi
covers large area of back from medial posterior trunk to anterior humerus
What are the origins of latissimus dorsi?
- spinal processes of T6-T12
- thoracolumbar fascia
- iliac crest
- inferior 3-4 ribs
What is the insertion of the latissimus dorsi?
-floor of the inter tubercular groove of the humerus
What are the actions of the latissimus dorsi?
- extension
- adduction
- medial rotation of the humerus
- downward rotation of the scapula
- raise body to arms when climbing
What nerve innervates the latissimus dorsi?
thoracodorsal nerve (C6-C8)
What artery supplies the latissimus dorsi?
thoracodorsal artery
Describe levator scapulae fibers and their location
- fibers pass inferiorly from origin to insertion
- located deep to sternocleidomastoid and trapezius
What is the insertion of levator scapulae?
Medial border of scapula superior to root of scapular spine
What is the origin of levator scapulae?
posterior tubercles of transverse processes of C1-C4