3.5 cervical vertebra

Hermizan Halihanafiah 1

ANATOMY MUSCULOSKELETAL

AXIAL SKELETON

CERVICAL VERTEBRAE


Vertebra Column

• Spine @ backbone

• Composed of a series of

bones called vertebrae.

• Vertebral column,

sternum and ribs form the

skeleton of the trunk of

the body.


Vertebrae

RibcageSternum


Function of Vertebral Column

• Functions as a strong, flexible rod with elements

that can be move forward, backward and

sideways, and rotate.

• Enclosing and protecting the spinal cord

• Supports the head

• Serves as a point attachment for the ribs, pelvic

girdle and muscles of the back.


Vertebral Column

• Early development is 33 bones.

• Grows up – several vertebrae in the sacral and

coccygeal regions fuse.

• Normal adults, typically contains 26 vertebrae.

• Consists: cervical , thoracic, lumbar, sacral and

coccyx vertebrae.

• cervical , thoracic, lumbar – movable

• sacral and coccyx vertebrae - immovable


Vertebra Column

• Distributed as follows:

1. 7 cervical vertebrae – neck region

2. 12 thoracic vertebrae – posterior to the

thoracic cavity

3. 5 lumbar vertebrae – support the lower back.

4. 1 sacrum – consists of 5 fused sacral

vertebrae.

5. 1 coccyx – consists of 4 fused coccygeal

vertebrae.


Parts of a Typical Vertebra

• Vertebrae in different regions of the spinal

column vary in size, shape, and details.

• Vertebrae typically consist:

1. Body

2. Vertebral arch

3. Processes


Body• Thick

• Disc shape anterior portion

• Weight bearing part of the vertebrae.

• Superior & inferior surface are roughened – attachment of

cartilaginous intervertebral disc.

• Anterior and lateral surface contain nutrien foramina,

opening for blood vessels deliver nutrient and O2 and

remove CO2 and wastes from bone tissues.


Vertebral Arch

• 2 short, thick processes called the pedicles, project

posteriorly from the vertebrae body to unite with the

flat laminae, to form the vertebrae arch.

• Vertebral arch extend posteriorly from the body of

the vertebra, together with the body and vertebral

arch surround the spinal cord by forming the

vertebral foramen.

• Vertebral foramen contain spinal cord, adipose

tissue and areolar connective tissue and blood

vessels.


Cont…

• Collectively, the vertebral foramina of all vertebrae

form the vertebral (spinal) cavity.

• The pedicles exhibit superior and inferior indentation

called vertebral notches.

• Superior and inferior vertebral notch are stacked on

top of ones another to form intervertebral foramen.

• Intervertebral foramen permits the passage of single

spinal nerve that passes to a spesific region of the

body.


Processes

• 7 processes arise from the vertebral arch.

• At the point where lamina and pedicle join, a

transverse process extends laterally on each

side.

• A single spinous process projects posteriorly

from the junction of the laminae.

• These 3 processes serve as points of

attachments for muscles.


Cont..• The remaining 4 processes forms joints with other

vertebrae above and below.

• 2 superior articular processes articulate with the 2 inferior articular processes of vertebrae above them.

• The articulating surfaces of articular processes called facets.

• Articulation between the bodies and articular facets of successive vertebrae are called intervertebral joint.


• Neural foramen

• Notches between adjacent

vertebrae.

• Allows for the passage of

the spinal nerve roots,

spinal artery, veins, nerve

plexus, and ligaments

Intervertebral Foramen


Intervertebral Discs• Intervertebral

fibrocartilage.

• Lie between adjacent vertebrae in the spine.

• Each disc forms a cartilaginous joint to allow slight movement of the vertebrae

• Acts as a ligaments to hold the vertebrae together.


Intervertebral Disc• Absorb shock

• Discs consist of an outer annulus fibrosus, which surrounds the inner nucleus pulposus.

• As people age, the nucleus pulposus begins to dehydrate, which limits its ability to absorb shock. The annulus fibrosus gets weaker with age and begins to tear.


Cervical Vertebrae• C1-C7

• C1, C2, C7 = Atypical , C2 – C6 = Typical

• The bodies are smaller than thoracic vertebrae.

• Vertebral arches are larger.

• Have one vertebral foramina, and two transverse

foramina.

• Vertebral foramina of cervical vertebrae are the largest in the

spinal column because they house the cervical enlargement

of the spinal cord.


Cont…• Each cervical transverse processes contain a

transverse foramen through which the vertebral artery,

vein and nerve pass.

• Spinous processes of C2-C6 are often bifid – split into

two parts.

• The first two cervical vertebra considerably from others.

• First cervical vertebrae (C1) called atlas, and second

cervical vertebrae (C2) called axis.


Typical Cervical Vertebra


Cervical 1 (Atlas)

• The atlas is a ring of bone with anterior and posterior arches

and large lateral masses.

• Lacks a body and a spinous process.

• Large vertebral foramen (triangular)

• The superior surface of the lateral masses called superior

articular facets are concave.

• Superior articular facets articulate with occipital condyle of

occipital bone to form atlanto – occipital joint.


Cont…• These articulation permits the movement for “yes”.

• Inferior surface of the lateral masses called inferior articular

facets, articulate with axis vertebrae to form atlanto-axial joint.

• Transverse process and transverse foramina of the atlas are

quiet large.

• The large vertebral foramina divide into 2 foramina by the

transverse ligament; larger posterior foramina (spinal cord)

and smaller anterior foramina (dens)


Atlas


Cervical 1 (Atlas)


Cervical 2 (Axis)

• Atypical cervical vertebra

• Have a body

• Peglike process called dens or odontoid process projects

up through anterior portion of the vertebral foramen of the

atlas.

• The dens makes a pivot on which the atlas and head

rotate, as in moving the head to signify “ NO”.


Cervical 2 (Axis)


Atlanto-Axial Joint


Cont…

• This arrangement allow side to side rotation of the head.

• The articulation formed between the anterior arch (facet) of

the atlas and dens of the axis, and between their

articulation facets (inferior and superior articular facets)

called the atlanto-axial joint.


Cervical 3-6 (C3-C6)

• Typical vertebra previously describe.

• Referred slide no 21 and 22.


Cervical 7 (C7)• Called the vertebra prominents.

• Has single large spinous process that can be felt at the

base of the neck.

• Spinous process is not bifid.

• Body is larger.

• Pedicles are directed more posteriorly than laterally.

• Inferior articular facets face more anteriorly than

downwards.

• Vertebral foramen, generally smaller than other cervical

vertebrae.


Cervical 7 (C7)

Vertebral ProminentsSpinous process not

bifid, large project posteriorly


Cervical 7 (C7)


MUSCLES OF THE NECK THAT MOVE THE HEAD

Balance and movement of the head on the

vertebral column involves several neck muscles.

• Sternocleidomastoid

• Semispinalis capitis

• Splenius capitis

• Longissimus capitis


Sternocleidomastoid

• Origin : sternal head from superior and anterior surface of manubrium of sternum; clavicular head from medial half of clavicle

• Insertion : mastoid process of temporal bone

• Action : bilaterally – flex cervical portion of vertebral column, flex head and elevate ribs during force inhalation

: unilaterally – laterally rotate and flex head to side opposite

contracting muscles.


Sternocleidomastoid (cont…)• Nerve supply (nerve

innervations)

- accessory (XI) nerve


Semispinalis Capitis

• Origin : transverse process of C7 and T1 – T7 vertebra.

• Insertion : occipital bone between superior and inferior nuchal line.

• Action : bilaterally extend head , unilaterally lateral rotate head to same side as contracting muscle.

• Nerve innervations : cervical and thoracic spinal nerves


Semispinalis Capitis


Splenius Capitis

• Origin : ligamentum nuchae and spinous process of C7 and T1 – T4

• Insertion : occipital bones and mastoid process of temporal bone.

• Action : Bilaterally extend head, unilaterally lateral rotate head to same side as contracting muscle.

• Nerve innervations : cervical spinal nerves


Splenius Capitis


Longissimus Capitis

• Origin : transverse process of T1 – T4 and

articular process of C4 – C7

• Insertion : posterior margin of mastoid process

of temporal bone.

• Action : Bilaterally extend head, unilaterally

lateral rotate head to same side as contracting

muscle.

• Nerve innervations : middle and inferior

cervical spinal nerves


Neck Flexion / Extension

Extension Flexion


Lateral Flexion


Head Rotation

3.5 cervical vertebra

Health & Medicine

hermizan halihanafiah

vertebrae body

vertebrae arch

lumbar vertebrae

vertebral arch

vertebrae ribcagesternum

vertebral foramina

fused sacral vertebrae