Muscles of the Back Flashcards
Back of the neck is supplied by dorsal rami of the _____ nerves.
cervical
Dorsal rami of C1 and C8 carry _____ axons only.
efferent; no sensory function!
The first layer of the back consists of:
latissimus dorsi and trapezius
The second layer of the back consists of:
splenius muscle, levator scapulae, rhomboid major and minor, serratus posterior superior and serratus posterior inferior muscle
Third layer of the back consists of:
erector spinae muscles
The fourth layer of the back consists of:
multifidus, rotators, intertransversii, and suboccipital muscles
Functionally, only the ____ group is involved in the movement of the vertebral column and maintaining posture.
deep (intrinsic muscles)
Deep (intrinsic) muscles are innervated by:
the dorsal rami of the spinal nerves
All muscles in the superficial group are supplied by
anterior rami of spinal nerves through brachial plexus except trapezius.
Superficial back muscles control ____ ____ movements as well as aid in respiration.
upper limb
The origin is the _____ end.
immovable
Insertion is the _____ end.
movabale
The ____ muscle is a large superficial back muscle that resembles a trapezoid.
trapezius
_____ _____ innervates the trapezius muscle.
accessory nerve
actions of the trapezius:
- retraction of the scapula
- depression of the scapula
- elevation of the scapula
- superiorly rotates glenoid cavity
- neck extension
Actions of the latissimus dorsi:
- medial rotation of shoulder joint
- extension of should joint
- adduction of shoulder joint
innervation of the latissimus dorsi
thoracodorsal nerve
Actions of the rhomboids
retract, elevate the scapula
innervation of the rhomboids
dorsal scapular nerve (C5)
Action of levator scapulae
elevation of the scapular only
innervation of the levator scapulae
dorsal scapular nerve
True muscles of the back and neck: Superficial layer
splenius capitis and splenius cervicis
True muscles of the back and neck: intermediate layer
iliocostalis, longissimus, and spinalis
True muscles of the back and neck: deep layer
semispinalis, multifidus, rotatores breves and rotatores longi