Muscle of Back Flashcards
What 4 things does vertebral column mobility depend on
- Thickness of intervertebral discs
- orientation of articular surfaces in Z joint
- Presence of the ribs
- Tension of the surrounding soft tissues (Joint capsule, muscles, ligaments)
A vertebral segment which has a ______ thickness of disk to height of vertebrae ratio has the most mobility
highest
What is the thickness of disk to height of vertebrae ratio in cervical vertebrae
2/5
What is the thickness of disk to height of vertebrae ratio in thoracic vertebrae
1/5
What is the thickness of disk to height of vertebrae ratio in lumbar vertebrae
1/3
Which portion of the spine has the thinest disks? Greatest?
cervical
lumbar
The articular surfaces in the cervical region are sitting in what plane?
almost horizontal
The articular surfaces in the thoracic region are sitting in what plane?
Coronal
The articular surfaces in the lumbar region are sitting in what plane?
turning into sagittal
What spinal region has the most flexion
lumbar
What spinal region has the most extension
cervical
What spinal region has the most lateral flexion
cervical
What lumbar region has the most rotation
cervical
what is the MAIN origina of lat dorsi
thoracolumbar fascia
Is the lat dorsi capable of dislocating the shoulder? why doesnt it?
yes but it doesnt because triceps oppose the downward pull with upward pull
Where does lat dorsi insert
floor of intertubercular sulcus of humerus
lat dorsi is the prime mover of what action
extension at GH joint
What is the reverse function of lat dorsi
Lift trunk
In what populations is the reverse function of lat dorsi important
people who are paralegiac - used in wheelchair transfers
What is the nerve supply and spinal segments of lat dorsi
thoracodorsal nerve C6, C7, C8
What is the nerve supply for trap
accessory nerve
O of rhomboid major?
Spinous process of T2-T5
O of rhomboid minor?
Spinous processes of C7-T1
What is the nerve supply of the rhomboids
Dorsal scapular nerve
C4, C5
O, I, Action, and nerve supply of serratus posterior superior
O - SP C7-T2, supraspinous ligaments, distal nuchal ligament
I - upper ribs
A - Elevates ribs accesory muscle in inspiration
NS - Ventral rami T2-T5
O, I, Action, and nerve supply of serratus posterior inferior
O - SP T11-L2 and supraspinous ligament
I - 8th-12th rib
A - depresses ribs - accessory muscle in respiration
NS - Ventral rami T9-T12
What is the O, I, A, and NS of splenius capitis
O - Spinous processes of C7-T3 vertebrae, nuchal ligament and supraspinous ligament
I - mastoid process
A - extension of head and cervical spine, ipsilateral rotation of head, lateral flexion of neck
NS - Cervical nerves 2 and 3
What is the O, I, A, and NS of splenius cervicis
O - SP of T3-T6 and supraspinous ligament
I - Transverse process of C1-C2
A - extension and side flexion of neck
NS - Lateral branches of posterior rami of lower cervical nerves
Erector spinae is comprised of which 3 logitudinal muscle bundles
- Ilio-costalis
- Longissimus
- Spinalis
____ muscles occupy the bony gutter between spinous and transverse processes
Transverso-spinalis
The transverso-spinalis muscle include with muscles
Semi-spinalis
Multifidus
Rotatores
What are the 3 other less talked about segmental muscular groups
- Interspinales
- Intertransversarii
- Levatores costarum
Rotation of vertebral column is primarily done by…
rotares
What is the O, I, A, and NS of levator costarum
O - TP of C7-T11
I - Upper margin of rib
A - Elevate ribs
NS - Dorsal rami
Which segmental muscle group can sometimes turn into a ligament by becoming fibrotic
intertransversarii
The occipital triangle is formed by…
- Obliquus capitis superior
- Obliquus capitis inferior
- Rectus capitis posterior major
What are 3 contents of the sub-occipital triangle
- Vertebral artery
- Greater occipital nerve (C2)
- Sub-occipital nerve (C1)
How does the sub-occipital triangle relate to headaches
The vertebral artery lies right inside i. any muscles could compress the artery if they spasm and cause significant changes in blood pressure inside cranium
