Neck And Trunk

Front 1

Typical Vertebrae

Body

Back 1

Cylindrical bone mass
Main weight-bearing part

Front 2

Typical Vertebrae

Intervertebral Disc

Back 2

Thick ring of fibrocartilage
Vertebral column shock absorber

Front 3

Typical Vertebrae

Interbody Joint

Back 3

Formed by two vertebral bodies and intervertebral disc

Front 4

Typical Vertebrae

Spinous Process

Back 4

Most easily palpated through skin and muscle
Typically points posterior but may be inferior as well (especially thoracic)

Front 5

Typical Vertebrae

Transverse Process

Back 5

Lateral projections
Muscles and ligaments attachments

Front 6

Typical Vertebrae

Vertebral Canal

Back 6

Houses and protects spinal cord

Front 7

Typical Vertebrae

Pedicles

Back 7

Short thick projections of bone connecting body of vertebrae to each transverse process

Front 8

Typical Vertebrae

Laminae

Back 8

Thin plates of bone forming posterior wall of vertebral canal
Connect each transverse process to spinous process base

Front 9

Typical Vertebrae

Superior and Inferior Articular Facets

Back 9

Inferior facets of one vertbera articulate with superior facets of vertebra below it
Together they make a facet (apophyseal) joint
Help guide vertebral motion

Front 10

Typical Vertebrae

Intervertebral Foramina

Back 10

Between adjacent vertebrae
Passageways for nerve roots entering or exiting vertebral column

Front 11

Cervical Vertebrae

Typical (C3-C7)

Back 11

Transverse foramina: Holes for vertebral arteries heading to brain in the transverse processes
Bordered posterior-laterally by uncinate processes
Most spinous processes are bifid

Front 12

Cervical Vertebrae

Atlas (C1)

Back 12

Two large concave superior facets sit on top of lateral masses to accept occipital condyles, forming atlanto-occipital j.

Front 13

Cervical Vertebrae

Axis (C2)

Back 13

Functions as vertical axis of rotation for rotary movements between head and cervical region

Front 14

Thoracic Vertebrae

Back 14

Inferiorly projected spinous processes
Large posterior-laterally projected transverse processes
Facet (apophyseal) joints are aligned nearly in frontal plane

Front 15

Lumbar Vertebrae

Back 15

Facet joints in upper lumbar region are oriented close to sagittal plane, transition toward frontal plane in lower regions

Front 16

Vertebral Segments and their planes

Back 16

Cervical is triplanar
Thoracic is frontal
Lumbar is sagittal

Front 17

Major ligaments

ligamentum flavum

Back 17

Limits flexion

Front 18

Major ligaments

supraspinous and interspinous ligaments

Back 18

attaches between adjacent spinous processes from C7 to sacrum
Limits flexion

Front 19

major ligaments

Intertransverse ligaments

Back 19

limits contralateral sidebending (lateral flexion)

Front 20

major ligaments

anterior longitudinal ligament

Back 20

adds stability to vertebral column
Limits extension or excessive lordosis

Front 21

major ligaments

posterior longitudinal ligament

Back 21

stabilizes vertebral column
limits flexion
reinforces posterior annulus fibrosis

Front 22

craniocervical region

Set of three articulations

Back 22

atlanto-occipital joint, atlanto-axial joint, intracervical joint

most mobile area of entire vertebral column

Front 23

craniocervical region

flexion and extension

Back 23

85 degrees of cervical extension

45-50 degrees of cervical flexion

Front 24

craniocervical region

axial rotation

Back 24

allows visual field to approach 360 degrees

C1 and attached cranium rotate as fixed unit relative to axis

Front 25

craniocervical region

lateral flexion

Back 25

allows about 40 degrees of lateral flexion to each side
Motion guided by incline of facet joints

Front 26

thoracolumbar region

flexion and extension

Back 26

combined motion of thoracic and lumbar vertebrae allows about 85 degrees of forward flexion
Allows about 35-40 degrees of extension

Front 27

thoracolumbar region

axial rotation

Back 27

allows only about 35 degrees of horizontal plane rotation in either direction

Front 28

thoracolumbar region

lateral flexion

Back 28

limited to about 45 degrees in either direction

Front 29

lumbosacral junction

Back 29

articulation between L5 and S1, weight transferred to pelvis
Facet joints of L5-S1 are oriented close to frontal plane to prevent lower spine from translating downhill

Front 30

sacroiliac joints

Back 30

nutation is anterior rotation of sacrum relative to each ilium
counternutation is posterior rotation of sacrum relative to each ilium
Primary function is to transfer forces of body weight to pelvis

Front 31

Innervation to craniocervical and trunk musculature

dorsal rami

Back 31

dorsal rami form short nerves that innervate most muscles of posterior neck and trunk

Front 32

Innervation to craniocervical and trunk musculature

ventral rami

Back 32

form cervical, brachial, and lumbosacral plexus and innervate most muscles of anterior-lateral trunk and neck

Front 33

anterior craniocervical (neck) muscles

superficial

Back 33

sternocleidomastoid
anterior, middle, and posterior scalenes

Front 34

anterior craniocervical (neck) muscles

deep

Back 34

longus colli
longus capitis
rectus capitis anterior
rectus capitis lateralis

Front 35

anterior craniocervical muscles

sternocleidomastoid

Back 35

O: sternum and clavicle
I: mastoid process
A: flexion of head and neck, contralateral rotation of head and neck, lateral flexion of head and neck
N: spinal accessory nerve (cranial nerve XI)

Front 36

anterior craniocervical muscles

scalenes

Back 36

O: transverse processes of the cervical vertebrae
I: first and second ribs
A: flexion of neck(anterior and middle scalenes, lateral flexion, assist with inspiration via elevation of first and second ribs

Front 37

posterior craniocervical muscles

suboccipital muscles

Back 37

obliquus capitis superior
obliquus capitis inferior
rectus capitis posterior minor
rectus capitis posterior major

Front 38

posterior craniocervical extensors

superficial cervical extensors

Back 38

splenius capitis: extension, lateral flexion, and ipsilateral rotation of head and neck
splenius cervicis: extension, lateral flexion, and ipsilateral rotation of neck

Front 39

anterior muscles of trunk

matching pairs

Back 39

rectus abdominis
external oblique
internal oblique
transverse abdominis

Front 40

anteior muscles of trunk

rectus abdominis

Back 40

O: pubis
I: xiphoid process and costal cartilages of ribs 5-7
I: intercostal nerves T7-T12
A: flexion of trunk, posterior pelvic tilt, increase intra-abdominal and intrathoracic pressure

Front 41

anterior muscles of trunk

external oblique

Back 41

O: lower eight ribs laterally
I: iliac crest and linea alba
A: flexion of trunk, posterior pelvic tilt, increase intra-abdominal and intrathoracic pressure, rotation of trunk to opposite side, lateral flexion of trunk
N: Intercostal nerves T8-T12

Front 42

anterior muscles of trunk

internal oblique

Back 42

O: inguinal ligament, iliac crest, thoracolumbar fascia
I: ribs 9-12, linea alba, and rectus sheath
A: flexion of trunk posterior pelvic tilt, increase intra-abdominal and intrathoracic pressure, lateral flexion of trunk, rotation of trunk to same side
N: intercostal nerves T8-T12

Front 43

anterior muscles of trunk

Transverse abdominis

Back 43

O: inguinal ligament, thoracolumbar fascia, cartilages of ribs 6-12
I: linea alba, contralateral rectus sheaths
A: increase intra-abdominal pressure, increase tension in thoracolumbar fascia
N: intercostal nerves T7-T12

Front 44

Other functionally associated muscles of anterior trunk

iliopsoas

Back 44

combo of iliacus and psoas major, primary hip flexor and also plays role in other motions of trunk and pelvis

Front 45

other functionally associated muscles of anterior trunk

quadratus lumborum

Back 45

attaches inferiorly to iliac crest, and superiorly to the 12th rib and transverse processes of L1-L4
bilateral activation of this muscle results in extension of lumbar spine

Front 46

posterior muscle groups of trunk

Back 46

erector spinae
transversospinal muscles
short segmental group

Front 47

posterior muscles of trunk

erector spinae

Back 47

run up and down spine vertically to control extension and some fine tuning
consist of three thin columns of muscles: spinalis, longissimus, iliocostalis

Front 48

posterior muscles of trunk

transversospinal muscles

Back 48

semispinalis, multifidus, rotators
lie deep to erector spinae, course in oblique direction from one vertebra's transverse processes to spinous process of another

Front 49

posterior muscles of trunk

actions of transversospinal muscles

Back 49

All are extensors of the vertebral column
Most can produce contralateral rotation
the more horizontal and shorter the muscle the more potential to produce horizontal plane rotation

Front 50

posterior muscles of trunk

short segmental group

Back 50

intertransversarus, interspinales muscles
Assists with lateral flexion
Effective at giving fine control over vertebral column, vertical stability in sagittal and frontal planes
Essential for postural alignment with sensory feedback