10.14 Vertebral Column And The Muscles Of The Back

Front 1

number of vertebrae in the vertebral column

Back 1

33

Front 2

number of vertebrae in the cervical region of the vertebral column

Back 2

7

Front 3

number of vertebrae in the thoracic region of the vertebral column

Back 3

12

Front 4

number of vertebrae in the lumbar region of the vertebral column

Back 4

5

Front 5

number of vertebrae in the sacral region of the vertebral column

Back 5

5 fused

Front 6

number of vertebrae in the coccygeal region of the vertebral column

Back 6

3-4 fused

Front 7

primary curves in the vertebral column

Back 7

thoracic and sacral
*develop during the fetal period, same direction as fetal vertebral column
*height difference in vertebrae (posterior higher)

Front 8

secondary curves in the vertebral column and when they arise

Back 8

cervical - when infants hold heads erect
lumbar - when infants stand/walk
*develop postnatally, opposite direction as fetal vertebral column
*height difference in intervertebral discs

Front 9

purpose of curvatures in the vertebral column

Back 9

1. align body's center of gravity
2. provide shock absorption during gait cycle

Front 10

abnormal curvature: kyphosis

Back 10

accentuated thoracic curvature; 'hunchback' or 'dowager's back'

cause: osteoporosis or poor posture

Front 11

abnormal curvature: lordosis

Back 11

accentuated lumbar curvature; 'swayback' or 'hollow back'

cause: weight gain/pregnancy, weak trunk muscles
**LORDS like to get FAT and have lots of BABIES

Front 12

abnormal curvature: scoliosis

Back 12

abnormal lateral curvature/rotation of vertebrae

Front 13

number of spinal nerve PAIRS housed and protected by the vertebral column

Back 13

31

Front 14

number of cervical spinal nerve pairs?
thoracic?
lumbar?
sacral?
coccygeal?

Back 14

8 cervical
12 thoracic
5 lumber
5 sacral
1 coccygeal (minor)

Front 15

some branches of spinal nerves come together to form...

Back 15

plexuses (brachial and lumbosacral)

Front 16

ventral root of the spinal nerve
- contains axons of _____ nerves
- conveys impulses _____ the spinal cord

Back 16

motor/away from

Front 17

dorsal root of the spinal nerve
- contains axons of _____ nerves
- conveys impulses _____ the spinal cord

Back 17

sensory/toward

Front 18

the dorsal and ventral roots form a _______ that conveys ____ axons

Back 18

spinal nerve/motor and sensory

Front 19

spinal nerves divide into ____ which convey ____

Back 19

dorsal and ventral rami/both motor and sensory axons

Front 20

the dorsal ramus conveys nerve axons to and from where? (three major categories)

Back 20

1. deep (intrinsic) muscles of the back
2. synovial joints of vertebral column
3. skin of the back

Front 21

the ventral ramus conveys nerve axons to and from where? (two major categories)

Back 21

1. upper and lower limbs
2. anterior/lateral body wall (torso)

Front 22

cell bodies of the motor nerves are found where?
what are these called?
where do they innervate?

Back 22

within spinal cord gray matter
"somatic motor nerves"
skeletal or voluntary muscles

Front 23

cell bodies of the sensory nerves are found where?
what are these called?
where do they innervate?

Back 23

dorsal root ganglion
"general sensory or somatic sensory nerves"
convey sensation, pain, touch, temperature into the spinal cord/CNS

Front 24

joints between the vertebral bodies are called?
what are these made of and designed for?

Back 24

intervertebral discs
cartilaginous joints - designed for weight bearing/strength

*provide stable/strong attachment between adjacent vertebrae

Front 25

two sections of an intervertebral disc and their purpose

Back 25

1. anulus fibrosus - outer concentric layers, fibrocartilage that adheres to vertebral bodies
2. nucleus pulposus - gelatinous, watery central mass; shock absorption

Front 26

joints between the articular processes of adjacent vertebrae
what kind of joints are these?

Back 26

facet joints (zygapophysial joints)
- synovial joints

Front 27

function of the facet (zygapophysial) joints

Back 27

individually: permit small amounts of gliding between vertebrae
collectively: motion in vertebral column
- can become arthritic
- each vertebrae has 4 of these joints

Front 28

space near the facet joints where the spinal nerve can exit the vertebral column

Back 28

intervertebral foramen
- arthritic facet joints: nerve impinged upon, and will have pain!

Front 29

anterior longitudinal ligament

Back 29

unites anterior surface of vertebral bodies
- prevent hyperextension

Front 30

posterior longitudinal ligament

Back 30

unites posterior surface of vertebral bodies - INSIDE vertebral canal

Front 31

supraspinous ligament

Back 31

connects spinous process from sacrum to C7, then expands into the ligamentum nuchae

Front 32

ligamentum nuchae

Back 32

broad, strong ligament of the neck --> attachment for cervical muscles

Front 33

interspinous ligament

Back 33

adjoin spinous processes

Front 34

intertransverse ligament

Back 34

adjoin transverse processes

Front 35

ligamentum flavum

Back 35

yellow, elastic fibers
adjoin adjacent lamina
prevent hyperflexion

Front 36

movements of the vertebral column affected by what four factors

Back 36

1. tension of joint capsule around facet joint
2. compressibility, elasticity, thickness of intervertebral disc
3. resistance of surrounding muscles/ligaments
4. SHAPE/ORIENTATION OF FACET JOINTS

Front 37

orientation of cervical facet joints and what type of motion allowed

Back 37

transverse plane orientation

multiaxial motion

Front 38

orientation of thoracic facet joints and what type of motion allowed

Back 38

frontal plane orientation

rotation/torsion

Front 39

orientation of lumbar facet joints and what type of motion allowed

Back 39

sagittal plane orientation

flexion/extension

Front 40

whiplash or football injuries can cause what kind of damage?

Back 40

hyperextension of the cervical region can tear the anterior longitudinal ligament
- can also have compression fractures/dislocations of cervical vertebrae because of horizontal orientation of facet joints in cervical region

Front 41

three main groups of back muscles

Back 41

1. superficial (extrinsic)
2. intermediate
3. deep (intrinsic)

Front 42

function of the superficial back muscles?
four main superficial back muscles?

Back 42

produce and control limb/shoulder movements

trapezius, latissimus dorsi, levator scapulae, rhomboids

Front 43

latissimus dorsi - origin (3 places)

Back 43

1. spinous processes of lower 6 thoracic vertebrae
2. thoracolumbar fascia
3. iliac crest

Front 44

latissimus dorsi - insertion

Back 44

intertubercular sulcus (bicipital groove) of the humerus

Front 45

latissimus dorsi - action

Back 45

extends, adducts, and medially rotates humerus
-climbing, rowing, push out of chair

Front 46

latissimus dorsi - innervation

Back 46

thoracodorsal nerve
* ventral rami of C6, C7, C8

Front 47

multi-layered fascia that surrounds/supports the intrinsic back muscles and is an attachment site for many muscles (like the lattisimus dorsi!)

Back 47

thoracolumbar fascia

Front 48

attachment sites of the thoracolumbar fascia

Back 48

spinous processes/transverse processes
- has anterior, middle, and posterior layers

Front 49

trapezius - origin (3 places)

Back 49

1. external occipital protuberance
2. nuchal ligament
3. spinous processes of C7-T12

Front 50

trapezius - insertion (3 places)

Back 50

1. lateral 1/3 of clavicle
2. acromion
3. spine of the scapula

Front 51

trapezius - action

Back 51

elevates, rotates, and retracts the scapula
- shrugs shoulders

Front 52

trapezius - innervations

Back 52

motor innervation: CN XI (spinal accessory nerve)
sensory innervation - cervical nerves C3-C4

Front 53

names of the two intermediate muscles of the back

Back 53

1. serratus posterior superior
2. serratus posterior inferior

*these look like ribbons

Front 54

function of the intermediate muscles

Back 54

assist in respiratory control

Front 55

function of the intrinsic muscles of the back

Back 55

move/stabilize the vertebral column
- aka the 'paraspinal muscles'
- further divided into superficial deep, intermediate deep, and deepest layers

Front 56

all intrinsic muscles of the back are innervated by what?

Back 56

dorsal rami of spinal nerves!!

Front 57

muscles in the superficial intrinsic layer
- name and location

Back 57

splenius muscles/cervical region

Front 58

splenius muscles - description, location, and action

Back 58

splenius capitis and cervicis
- thick, flat muscles from the vertebral column that insert near the base of the skull (cover the "Suboccipital Triangle"
- action: extend/rotate head and neck

Front 59

muscles in the intermediate intrinsic layer
- name and function

Back 59

erector spinae muscle complex
- 3 muscle masses: iliocostalis, longissimus, and spinalis
- postural muscles; extension and flexion of the spine

Front 60

muscles in the deepest intrinsic layer
- name, location, and function

Back 60

transversospinalis muscle complex
- course from transverse process to spinous process of more superior vertebrae
- postural, rotational, and proprioceptive muscles

3 muscle segments
1. semispinalis (superficial)
2. multifidus (intermediate)
3. rotatores (deepest)

Front 61

bottom line concept: what are the true/intrinsic back muscles and what are they innervated by?

Back 61

splenius, erector spinae, and transversospinalis complex; innervated by dorsal rami of spinal nerves

Front 62

bottom line concept: latissimus dorsi

Back 62

muscle of the upper extremity, innervated by ventral rami of spinal nerves (thoracodorsal nerve C6, C7, and C8)

Front 63

bottom line concept: trapezius

Back 63

motor inervated by CN XI (the spinal accessory nerve)

Front 64

bottom line concept: thoracolumbar fascia

Back 64

multi-layered sheath that surrounds and supports the intrinsic back muscles

Front 65

bottom line concept: posterior longitudinal ligament

Back 65

is located within the vertebral canal