Back Muscles - Origin, Insertion, Innervation

Front 1

trapezius - Origin

Back 1

External occipitar protuberance, medial third of superior nuchal line, nuchal ligament, SP of C7-T12

Front 2

trapezious- insertion

Back 2

lateral third of the clavicle; acromion and spine of the scapula

Front 3

trpezious - action

Back 3

elevates and depresses the scapula (descending/superior), rotates the scapula superiorly(middle); retracts scapula(ascending/inferior)

Front 4

trapezious- innervation

Back 4

motor: spinal accessory (XI), proprioception: C3-C4 (sensory)

Front 5

trapezious-artery

Back 5

transverse cervical artery

Front 6

latissimus dorsi - Origin

Back 6

Spinous processes of T7 to the sacrum, posterior third of the iliac crest, ribs 10-12, sometimes from the inferior angle of the
scapula

Front 7

latissimus dorsi - insertion

Back 7

floor of the intertubercular groove of the humerous

Front 8

latissimus dorsi-innervation

Back 8

thoracodorsal nerve (C6, 7, 8) from the posterior chord of the brachial plexus.

Front 9

latissimus dorsi - action

Back 9

extends, adducts and medially rotates humerous.
Raises body during climbing

Front 10

latissimus dorsi-artery

Back 10

thoracodorsal artery

Front 11

trapezious- Clinical

Back 11

Injury of spinal accessory nerve
1. the primary clinical manifestation of spinal accessory nerve palsy is a marked ipsilateral
weakness when the shoulders are elevated ( shrugged ) against resistance

Front 12

latissimus dorsi - Clinical

Back 12

Injury to thoracodorsal nerve
1. during surgery in the inferior part of the axilla, the thoracodorsal nerve supplying the latissimus dorsi at risk of injury

Front 13

Rhomboideus Major, Minor & Levator Scapulae - Clinical

Back 13

Injury to dorsal scapular nerve
1. injury to the dorsal scapular nerve ( the nerve to rhomboids ) affects the actions of these
muscles
2. if the rhomboids of one side are paralyzed, the scapula on the affected side is located farther
from the midline than that on the other side

Front 14

Triangle of auscultation
Boundaries

Back 14

inferiorly- upper border of the latissimus dorsi
laterally- medial border of scapula
medially - lateral borer of trapezious
Floor is formed by the rhomboideus major

Front 15

Triangle of auscultation
Clinical importance

Back 15

This triangular gap in the thick back musculature is a good place to examine the posterior segments of the lungs with a stethoscope

Front 16

Levator Scapulae-Origin

Back 16

Transverse Process of C1-C4

Front 17

Levator Scapulae-Inertion

Back 17

Medial border of scapula superior root of scapular spine (dorsal surface)

Front 18

Levator Scapulae-Innervation

Back 18

dorsal scaula nerve (C5root)
C3-C4 nerves

Front 19

Rhomboideus minor-Origin

Back 19

nuchal ligament
SP C7-T1

Front 20

Rhomboideus minor-Insertion

Back 20

the smooth triangular area at the medial end of scapular spine ( dorsal surface )

Front 21

Rhomboideus minor-Innervation

Back 21

Dorsal scapular nerve (C5 root)

Front 22

Rhomboideus minor-Actions

Back 22

. retracts the scapula
2. rotates it to depress the glenoid cavity
3. fixes the scapula to the thoracic wall

Front 23

Levator Scapulae-Actions

Back 23

1. elevates the scapula
2. tilts its glenoid cavity inferiorly by rotating the scapula

Front 24

Rhombodieus major-Origin

Back 24

spinous process of T2 - T5 vertebrae

Front 25

Rhombodieus major-Insertion

Back 25

into the medial border of scapula from the level of spine to inferior angle ( dorsal surface )

Front 26

Rhombodieus major-Innervation

Back 26

Dorsal scapular nerve (c5 root)

Front 27

Rhombodieus major-Actions

Back 27

1. retracts the scapula
2. rotates it to depress the glenoid cavity
3. fixes the scapula to the thoracic wall

Front 28

Injury to the dorsal scapular nerve

Back 28

. if the rhomboids of one side are paralyzed, the scapula on the affected side is located farther from the midline than that on the other side

Front 29

Serratus posterior superior-Origin

Back 29

. ligamentum nuchae
2. spinous process of C7 - T3 vertebrae

Front 30

Serratus posterior superior- Insertion

Back 30

the superior borders of 2nd to 4th ribs

Front 31

Serratus posterior superior-innervation

Back 31

the 2nd to 5th intercostal nerves

Front 32

Serratus posterior superior-actions

Back 32

elevate the ribs

Front 33

Serratus posterior inferior -Origin

Back 33

the spinous processes T11 to L2 vertebrae

Front 34

Serratus posterior inferior-Origin

Back 34

inferior borders of 8th to 12th ribs near the angles

Front 35

Serratus posterior inferior-innervation

Back 35

ventral rami of 9th to 12th thoracic spinal nerves

Front 36

Serratus posterior inferior-insertion

Back 36

the inferior borders of 8th to 12th ribs near the angles

Front 37

Serratus posterior inferior-Actions

Back 37

depresses the ribs

Front 38

Splenius-Origin

Back 38

. nuchal ligament ( ligamentum nuchae )
2. spinous processes of C7 - T3 ( T4 )vertebrae

Front 39

Splenius (Capitis & Cervicis have same)-Origin

Back 39

. nuchal ligament ( ligamentum nuchae )
2. spinous processes of C7 - T3 ( T4 )vertebrae

Front 40

Splenius capitis - Insertion

Back 40

1. to the mastoid process of the temporal bone
2. lateral third of the superior nuchal line of the occipital bone

Front 41

Splenius capitis- direction of fibers

Back 41

fibers run superolaterally

Front 42

Splenius cervicis - Insertion

Back 42

into the tubercles of transverse processes of C1 - C3 (C4 ) vertebrae

Front 43

Splenius (Capitis & Cervicis have same)-Innervation

Back 43

by the posterior / dorsal rami of spinal nerves

Front 44

Actions of Splenius - acting alone

Back 44

, laterally flex neck and rotate head to side of active muscles

Front 45

Actions of Splenius - acting together

Back 45

they extend head and neck

Front 46

Erector spinae - Origin

Back 46

. from the posterior part of the iliac crest
2. posterior surface of sacrum
3. lower lumbar and sacral spinous processes
4. supraspinous ligaments

Front 47

Erector spinae-
Iliocostalis - lumborum, thoracis and cervicis -
Insertion

Back 47

1. to the angles of the lower ribs
2. cervical transverse processes

Front 48

Erector spinae- Longissimus - thoracis, cervicis and capitis -
Insertion

Back 48

1. to the ribs between the tubercles and angles
2. to the transverse processes of thoracic and cervical regions
3. mastoid process of temporal bone

Front 49

Erector Spinae - Spinalis - thoracis, cervicis and capitis
Insertion

Back 49

1. to the spinous processes in the upper thoracic region
2. to the cranium

Front 50

Erector Spinae - Innervation (ALL)

Back 50

Nerve supply by the posterior / dorsal rami of spinal nerves

Front 51

Erector Spinae- Actions - Bilaterally

Back 51

they extend vertebral column and head

Front 52

Erector Spinae- Actions - Unilatterally

Back 52

laterally flex vertebral column

Front 53

Transversospinalis - Semispinalis -Origin

Back 53

from the transverse processes of C4 - T12 vertebrae

Front 54

Transversospinalis- Semispinalis - thoracis, cervicis and capitis - Insertion

Back 54

1. to the occipital bone
2. spinous processes of thoracic and cervical regions

Front 55

Transversospinalis- Semispinalis - innervation

Back 55

by the posterior / dorsal rami of spinal nerves

Front 56

Transversospinalis- Semispinalis - Actions

Back 56

1. extends the head, thoracic and cervical regions of the vertebral column
2. rotate them contralaterally

Front 57

Multifidus - Origin

Back 57

1. posterior sacrum
2. posterior superior iliac spine of ilium
3. aponeurosis of erector spinae
4. sacroiliac ligaments
5. mamillary processes of lumbar vertebrae
6. transverse processes of T1 - T3
7. articular processes of C4 - C7

Front 58

Multifidus - Insertion

Back 58

the spinous processes of vertebrae above, 2 to 4 segments

Front 59

Multifidus - Innervation

Back 59

the posterior / dorsal rami of spinal nerves

Front 60

Multifidus - Action

Back 60

Action is to stabilize the vertebrae during local movements of the vertebral column

Front 61

Rotatores -
Origin

Back 61

the transverse processes of vertebrae ( best developed in the thoracic region )

Front 62

Rotatores -
Insertion

Back 62

into the junction of lamina and transverse process or spinous process of vertebra above their origin, 1 to 2 segments

Front 63

Rotatores - Innervation

Back 63

the posterior / dorsal rami of spinal nerves

Front 64

Rotatores - Actions

Back 64

1. stabilize the vertebrae and assists with the local extension and rotatory movements of
vertebral column
2. may function as organs of proprioception

Front 65

Interspinalis - Origin

Back 65

the superior surfaces of spinous processes of cervical and lumbar vertebrae

Front 66

Interspinalis - Insertion

Back 66

into the inferior surface of the spinous processes of the vertebrae above the origin

Front 67

Interspinalis - Innervation

Back 67

the posterior / dorsal and anterior / ventral rami of spinal nerves

Front 68

Interspinalis - Actions

Back 68

to aid in extension and rotation of the vertebral column

Front 69

Intertransversarii - Origin

Back 69

from the transverse processes of cervical and lumbar vertebrae

Front 70

Intertransversarii - Insertion

Back 70

into the transverse processes of adjacent vertebrae

Front 71

Levatores costorum- Origin

Back 71

the transverse processes of C7 and T1 - T11 vertebrae

Front 72

Levatores costorum-Insertion

Back 72

on the rib between the tubercle and angle

Front 73

Levatores costorum-Innervation

Back 73

the posterior / dorsal rami of C8 - T11 spinal nerves

Front 74

Levatores costorum-actions

Back 74

. elevate the ribs
2. assists respiration
3. assists with the lateral flexion of vertebral column

Front 75

Back strains

Back 75

is a common injury in people who participate in sports, results from

Front 76

Back strain results from

Back 76

involves some degree of stretching or microscopic tearing of muscle fibers
3. the muscle usually involved is the erector spinae

Front 77

Back Spasm

Back 77

1. a sudden involuntary contraction one or more muscle groups

Front 78

Back Sprain

Back 78

1. is an injury in which only ligamentous tissue, or the attachment of ligament to the bone is
involved without dislocation or fracture
2. it results from excessively strong contractions related to movements of the vertebral column,
such as excessive extension or rotation

Front 79

Suboccipital region

Back 79

Located in the upper back part of the neck, inferior to the occipital region of the head, including the posterior aspects of C1 and C2 vertebrae

Front 80

Suboccipital triangle

Back 80

Lies deep to the trapezius and semispinalis capitis

Front 81

Four muscles in the suboccipital region

Back 81

1. rectus capitis posterior major
2. rectus posterior minor
3. superior oblique
4. inferior oblique

These are mainly postural muscles and all the above four muscles are innervated by subooccipital nerve ( posterior / dorsal ramus of C1 )

Front 82

Rectus capitis posterior major - Origin

Back 82

from the spinous process of C2 ( axis )

Front 83

Rectus capitis posterior major-Insertion

Back 83

into lateral part of the inferior nuchal line of occipital bone

Front 84

Rectus capitis posterior major-Innervation

Back 84

are innervated by subooccipital nerve ( posterior / dorsal ramus of C1 )

Front 85

Rectus capitis posterior minor-
Origin

Back 85

from the posterior tubercle of the posterior arch of C1 ( atlas )

Front 86

Rectus capitis posterior minor - Insertion

Back 86

into the medial part of the inferior nuchal line of occipital bone

Front 87

Inferior oblique of the head ( obliquus capitis inferior )-Origin

Back 87

from the posterior tubercle of the posterior arch of C2 ( axis )

Front 88

Inferior oblique of the head ( obliquus capitis inferior )-Insertion

Back 88

into the transverse process of C1 ( atlas )

Front 89

Superior oblique of the head ( obliquus capitis superior )-Origin

Back 89

from the transverse process of C1 ( atlas

Front 90

Superior oblique of the head ( obliquus capitis superior )- Insertion

Back 90

into occipital bone between the superior and inferior nuchal lines

Front 91

Suboccipital triangle

Back 91

Boundaries
Superomedially by the rectus capitis posterior major

Superolaterally by the superior oblique

Inferolaterally by the inferior oblique

Floor
1. posterior arch of the atlas
2. posterior atlanto - occipital membrane

Roof by the semispinalis capitis

Front 92

Contents of the Suboccipital triangle

Back 92

1. vertebral artery
2. suboccipital nerve ( posterior / dorsal ramus of C1 )

Front 93

Suboccipital triangle -Clinical
Reduced blood supply to the brain stem

Back 93

. when blood flow through these arteries is reduced, as occurs with arteriosclerosis
3. under these conditions, prolonged turning of the head, as occurs when backing up a motor
vehicle, may cause light - headedness, dizziness and other symptoms from the interference
with the blood supply to the brainstem

Front 94

Spinal Cord

Back 94

. it begins as the continuation of the medulla oblongata, the caudal part of the brain stem
3. in the adult, the length of the cord is 42 - 45 cm long, extends from the foramen magnum in the occipital bone to the L1 or L2 vertebra
4. its tapering inferior end is the conus medullaris, may terminate as high as T12 and as low as L3 vertebra

Front 95

Spinal cord enlargements

Back 95

It is enlarged in two regions in relationship to innervation of the limbs

Front 96

Cervical enlargement

Back 96

1. extends from C4 through T1 segments of the cord
2. most of the anterior / ventral rami of the spinal nerves arising from it form the brachial plexus of nerves that innervates the upper limb

Front 97

Lumbosacral ( Lumbar ) enlargement

Back 97

1. extends from T11 through S1 segments of the cord
2. the anterior / ventral rami of the spinal nerves arising from this enlargement make up the lumbar and sacral plexuses of nerves, that innervate the lower limb

Front 98

Spinal nerve roots

Back 98

1. the portion of the spinal cord giving rise to the rootlets and roots that ultimately form one
bilateral pair of spinal nerves
2. it is designated as a spinal cord segment

Front 99

Spinal nerves

Back 99

1. 31 pairs are attached to the spinal cord
2. they exit the vertebral canal through the intervetebral foramina
3. in 50% of the people, the first cervical nerve ( C1 ) lacks posterior roots and coccygeal nerve
be absent

Cervical 8
Thoracic 5
Lumbar 5
Sacral 5
Coccygeal 1

Front 100

Cauda equine -

Back 100

1. formed by the loose bundle of spinal roots arising from the lumbosacral enlargement and
the conus medullaris – both dorsal and ventral root together.
2. they course within the lumbar cistern of CSF, caudal to the termination of the spinal cord
3. resembles a horse’s tail

Front 101

Filum terminale – L1-Coccyx 1 –

Back 101

connective tissue, no neural tissue, forms coccyx ligament where it attaches to the coccyx, anchors the spinal chord

Front 102

Filum terminale arises from

Back 102

the tip of the conus medullaris

Front 103

Filum terminale descends among

Back 103

the spinal nerve roots in the cauda equina

Front 104

Filum terminale is the reminant of

Back 104

the caudal part of the spinal cord

Front 105

Pial part of the filum terminale

Back 105

its proximal end - filum terminale internum )

Front 106

Filum terminale consists of

Back 106

vestiges of neural tissue, connective tissue and neurological tissue covered by pia mater

Front 107

Filum terminale perforates

Back 107

the inferior end of the dural sac, gaining a layer of dura

Front 108

filum terminale externum

Back 108

it continues through the sacral hiatus as the dural part of the filum terminale to attach to the dorsum of the coccyx

Front 109

Function of the filum terminale

Back 109

Is an anchor for the inferior end of the spinal cord and spinal meninges

Front 110

Structure of spinal nerve

Back 110

31 pairs of spinal nerves are attached to the spinal cord

Front 111

Dorsal root of the spinal nerve

Back 111

Arises from the dorsal surface of the cord, contains afferent ( sensory ) fibers from the skin, subcutaneous and deep tissues and often from the viscera

Front 112

The cell bodies of somatic axons making up the ventral root are in

Back 112

the ventral gray horns

Front 113

Ventral root of the spinal nerve

Back 113

Arises from the ventral surface of the cord, contains efferent ( motor ) fibers to skeletal muscle and many contain presynaptic autonomic fibers

Front 114

Location of
Filum Intraduale
Filum Extradurale

Back 114

Filum Intraduale L1-S2
Filum Extradurale S2-Coccyx 1

Front 115

( dorsal root ganglion )

Back 115

The cell bodies of axons making up the dorsal roots are in the spinal ganglion

Front 116

The dorsal ramus

Back 116

supplies the skin and true muscles of the back

Front 117

The ventral ramus

Back 117

supplies the limbs and the rest of the trunk

Front 118

Ischemia spinal cord

Back 118

. deficient blood supply to ( ischemia of ) the spinal cord, affects its function and can lead to
muscle weakness and paralysis
3. patients undergoing surgeries, those with ruptured aneurysms of the aorta or occlusion of
anterior segmental medullary artery, may lose all sensation and voluntary movement inferior
to the level of impaired blood supply to the spinal cord ( paraplegia )

Front 119

Paraplegia

Back 119

is the loss of all sensation and voluntary movements inferior to the level of impaired blood supply to the spinal cord

Front 120

Spinal cord shock is,

Back 120

the protrusion of a cervical IV intervetebral disc into the vertebral canal after a neck injury, associated with the paralysis inferior to the site of the lesion

Front 121

Lumbar spondylosis (

Back 121

degenerative joint disease )
1. causes localized pain and stiffness
2. pressure may produce sensory and motor symptoms in the area of distribution of the involved
spinal nerve

Front 122

Lumbar spondylosis
The causes are

Back 122

1. encroachment of the vertebral canal by a protruding IV intervetebral disc
2. by swollen ligamentum flava
3. resulting from osteoarthritis of the zygapophyseal joints

Front 123

Cervical spondylosis is often accompanied by

Back 123

1. swollen ligamtum flava
2. osteoarthritis of the zygapophyseal joints
3. this may cause pressure on the cervical spinal nerve roots and / or the spinal cord
4. resulting in various neurological signs and symptoms

Front 124

Osteophytes

Back 124

1. in some olderly people, the nucleus pulposus of the intervertebral disc degenerate
2. leading to formation of bony outgrowth, with mostly asymptomatic
3. but may produce pressure on the spinal nerve roots and cause sensory and motor symptoms

Front 125

Transection of the spinal cord results in

Back 125

loss of all sensation and voluntary movement inferior to the lesion

Front 126

Transection at level C1 - C3

Back 126

1. no function below head level
2. a ventilator is required to maintain respiration

Front 127

Transection at level C4 - C5 ( Quadriplegia )

Back 127

1. no function of upper and lower limbs
2. respiration occurs

Front 128

Transection at level C6 - C8

Back 128

1. loss of lower limb function combined with a loss of hand and a variable amount of upper limb
function
2. the individual may be able to self - feed or propel a wheelchair

Front 129

Transection at level T1 - T9 ( Paraplegia )

Back 129

1. paralysis of both lower limbs
2. the amount of trunk control varies with the height of the lesion

Front 130

Transection at level T10 - L1

Back 130

1. some thigh muscles function
2. may allow walking with long leg braces

Front 131

Transection at level L2 - L3

Back 131

1. retention of most leg muscle function
2. short leg braces may be required for walking