Chapter 8 Vertebral Column Anatomy

4 functions of the vertebral column:

- encloses and protects the spinal cord - acts as a support for the trunk - supports the skull superiorly - provides for attachment for the deep muscles of the back and ribs laterally

How much of the length of the vertebral column does the intervertebral disks make up

1/4

The zygapophyseal joints of the thoracic region, except the inferior articular processes of the twelfth vertebrae, angle anteriorly approximately _________________________ degrees to form an angle of ________________________ degrees (open anteriorly) to midsagittal plane of body

15-20 70-75

2 parts of the vertebral arch:

2 pedicles 2 laminae

Arise from the junction of the pedicles and laminae to articulate with the vertebrae above and below

2 superior and 2 inferior articular processes

How many vertebral segments in the upper three regions of the vertebral column?

24

______________% of L1-2 and L2-3 zygapophyseal joints are shown on an AP projection, and a small percentage of L4-5 and L5-S1 joints are seen on a lateral projection

25%

How many foramina do the cervical vertebrae contain?

3

The zygapophyseal joints of the lumbar region are inclined posteriorly from the coronal plane, forming an average angle (open posteriorly) of __________________________ degrees to the midsagittal plane of body

30-60

How many total bones make up the vertebral column?

33

How many curves does the vertebral column have?

4

The intervertebral foramina of the cervical region are directed at a ______________________ angle from the midsagittal plane of the body and at inferior angle of ______________________ to the horizontal plane of the body; so what CR and pt angulation is need for proper demonstration of these froamina

45-degree 15 degrees 15-degree longitudinal angulation of CR 45-degree medial rotation of the pt

The spinous process of the ___________________________ lumbar vertebra is smaller and shorter, and the transverse processes are much thicker than those of the upper lumbar vertebrae

5th

The body of which segment of the lumbar vertebrae is considerably deeper in front than behind, giving it a wedge shape that adapts it for articulation with the sacrum

5th segment

Numerous upper zygapophyseal joints have no angle, and many lower ones have an angle of _______________ degrees or more

60

How many cervical, thoracic, lumbar, sacral, coccygeal vertebrae are there?

7 Cervical, 12 Thoracic, 5 lumbar, 5 sacral, 3-5 coccygeal

To show the zygapophyseal joints of the thoracic region, the pt's body must be rotated _________________________ degrees from the anatomic position or _________________________ degrees from the lateral position

70-75 15-20

The joints created by the joining of the superior articular processes of the axis and the inferior articular processes of the atlas are clearly visualized in what projection if pt is properly positioned

AP projection

Kyphosis

Abnormally increased anterior concavity (posterior convexity) in the thoracic curvature

Lordosis

Abnormally increased anterior convexity (posterior convexity) of the cervical and lumbar spine

Clay shoveler's fracture

Avulsion fracture of the spinous process in the lower cervical and upper thoracic region

Why is spondylolisthesis of radiographic importance?

Because oblique-position radiographs show the "neck" area of the "Scottie dog"

Spondylolysis

Breaking down of the vertebra

The spinous process of this vertebra is easily palpable at the posterior base of the neck and is a guide in localizing other vertebrae

C7

Jefferson fracture

Comminuted fracture of the ring of C1

Spina bifida

Failure of the posterior encasement of the spinal cord to close

Spondylolisthesis

Forward displacement of a vertebra over a lower vertebra, usually L5-S1

Hangman's fracture

Fracture of the anterior arch of C2 owing to hyperextension

Compression fracture

Fracture that causes compaction of bone and a decrease in length or width

Scheuermann disease or adolescent kyphosis

Kyphosis with onset in adolescence

Scoliosis

Lateral deviation of the spine with possible vertebral rotation

Herniated nucleus pulposus

Rupture or prolapse of the nucleus pulposus into the spinal canal

The cervical and lumbar curves are called ________________________ because they develop after birth

Secondary curves

What is the purpose of the vertebral column developing a second or compensatory curve in the opposite direction with scoliosis?

To keep the head centered over the feet

Forms the central axis of the skeleton and is centered in the midsagittal plane of the posterior part of the trunk

Vertebral Column

When does the cervical curve develop?

When an infant begins to hold the head up at about 3-4 months of age and begins to sit up alone at about 8-9 months of age

When does the lumbar curve develop?

When the child begins to walk at about 1 - 1 1/2 years of age

At the back of the root of the transverse process of the lumbar vertebrae

accessory process

Large, winglike lateral masses on each side of the sacral base

ala

Outer fibrocartilaginous disk that surrounds the nucleus pulposus of the intervertebral disks

annulus fibrosus

These parts of the atlas extend between the lateral masses

anterior and posterior arches

Parts of the atlas:

anterior arch posterior arch 2 lateral masses 2 transverse processes

What is the result of small transversely located, oblong body with slightly elongated anteroinferior borders?

anteroposterior overlapping of the bodies in the articulated column

The inferior surface of the _______________________ of the sacrum has an oval facet for articulation with the coccyx and sacral cornua

apex

This part of the sacrum is directed posteriorly and inferiorly

apex

The superior and inferior surfaces of the bodies of the vertebra are flattened and are covered by a thin plate of ________________________________

articular cartilage

Together the superior and inferior articular processes of the typical cervical vertebra form short, thick columns of bone called _____________________________________

articular pillars

A large articular process at the superoanterior part of the lateral surface of each ala for articulation with similarly shaped processes on the iliac bones of the pelvis

articular surface

Articulation formed by the anterior arch of the atlas rotating around the dens of the axis Type: Movement:

atlantoaxial joint 2 lateral synovial gliding, 1 medial synovial pivot (dens) both freely movable

Articulations between the atlas and the occipital bone Type: Movement:

atlantooccipital joints synovial ellipsoidal freely movable

The first cervical vertebra (C1), a ringlike structure with no body and a very short spinous process

atlas

Second cervical vertebra (C2), has a strong conical process arising from the upper surface of its body

axis

This part of the sacrum is broad and directed obliquely, superiorly, and anteriorly

base

Does the palpable tip of each spinous process of the fifth to ninth thoracic vertebrae correspond in position to the interspace above or below the vertebra from which it projects?

below

Anterior mass of the vertebra, approximately cylindric in shape and is composed largely of cancellous bony tissue covered by a layer of compact tissue, has flattened posterior surface from superior aspect and concave anterior and lateral surfaces from lateral aspect

body

2 main parts of the vertebra:

body vertebral arch

The body of the vertebra is composed largely of _________________________________

cancellous bony tissue covered by a layer of compact tissue

The average angle of the zygapophyseal joints increase from __________________________ to _______________________ L1-2 at ____________________ degrees L2-3 at ___________________ degrees L3-4 through L5-S1 at ___________________ degrees

cephalad to caudad 15 30 45

Superior thoracic bodies resemble bodies of which vertebrae?

cervical

The least pronounced of the curves of the vertebral column

cervical curve

The seven superiormost vertebrae that occupy the region of the neck

cervical vertebrae

5 groups of the vertebral column:

cervical vertebrae thoracic vertebrae lumbar vertebrae sacral vertebrae coccygeal vertebrae

4 curves of the vertebral column:

cervical, thoracic, lumbar, and pelvic

Projects superiorly from the posterolateral aspect of the first coccygeal segment to join the sacral cornua

coccygeal cornua

Terminal vertebrae, also in pelvic region, vary from three to five in number in adults

coccygeal vertebrae

Composed of three to five (usually four) rudimentary vertebrae that have a tendency to fuse into one bone in the adult; it diminishes in size from its base inferiorly to its apex, from its articulation with the sacrum, it curves inferiorly and anteriorly, often deviating from the midline of the body

coccyx

When viewed posteriorly, the normal lumbar curve can correctly be referred to as ____________________________________

concave posteriorly

The vertebral curves are discussed in reference to the anatomic position and are referred to as ___________________________________ or ____________________________________

convex anteriorly concave anteriorly

The posterolateral margins of each thoracic body have _____________________________________ for articulation with the heads of the ribs

costal facets

Articulations between tubercles of the ribs and the transverse processes of the thoracic vertebrae Type: Movement:

costotransverse joints synovial gliding freely movable

Articulations between the heads of the ribs and the bodies of the vertebrae in the thoracic region Type: Movement:

costovertebral joints synovial gliding freely movable

The __________________________ of the vertebral column arch anteriorly and posteriorly from the midcoronal plane of the body

curves

Which body position shows most clinically significant lumbar zygapophyseal joints (L3-S1)

customary 45-degrees oblique position

What kind of facets do the bodies of the second through eighth thoracic vertebrae contain superiorly and inferiorly?

demifacets

Strong conical process arising from the upper surface of its body, is received into the anterior portion of the atlantal ring to act as a pivot or body for the atlas

dens (odontoid process)

The anterior portion of the ring of the atlas receives the ____________________ of the axis, an the posterior portion transmits the proximal spinal cord

dens (odontoid process)

Are interposed between the vertebrae and act as cushions

disks of fibrocartilage (intervertebral disks)

Except for the eleventh and twelfth pairs, each process of the thoracic vertebrae has on the anterior surface of its extremity a small concave ____________________ for articulation with the tubercle of the rib

facet

The articulating surfaces of the four articular processes that are covered with fibrocartilage

facets

The pelvic segments in the two lower regions are called ______________________________________

false or fix vertebrae

The sacrum is more acutely curved, with its greatest curvature in the lower half of the bone; it also lies in a more oblique plane, which results in a sharper angle junction of the lumbar and pelvic curves. Is this a male or female?

female

Are the lumbar and pelvic curves more pronounced in males or females? Why?

females they have a more acute angle at the lumbosacral junction

Bodies of the thoracic vertebrae increase in size from the __________________ to ___________________ vertebrae

first-twelfth

4 movements permitted in the vertebral column by the combined action of the joint are:

flexion extension lateral flexion rotation

Rupture or protrusion of the nucleus pulposus of the iintervertebral disks into the vertebral canal, impinging on a spinal nerve

herniated nucleus pulposus (HNP) or herniated disk

What causes HNP of the lumbar region? What can this cause?

improper body mechanics or poor posture considerable discomfort and pain

From the second cervical vertebra to the superior part of the sacrum the width of the spine gradually _____________________ and then it ______________________ sharply

increases decreases

Each lateral mass of the atlas bears a ________________________________ and a _________________________________

inferior and superior articular process

Each _________________________________________ has an articular facet on its anterior surface

inferior articular process

Separate the vertebral bodies forming a cartilaginous intervertebral joints

intervertebral disks

By the articulation with the vertebrae above and below, the notches form _______________________________________ for the transmission of spinal nerves and blood vessels

intervertebral foramina

The ________________________________ of the lumbar region are situated at right angles to the midsagittal plane of the body, except for the fifth, which turns slightly anteriorly

intervertebral foramina

The _________________________________________ of the thoracic region are perpendicular to the midsagittal plane of the body; they are clearly shown with the pt in what position?

intervertebral foramina lateral

Articulations between the two vertebral bodies Type: Movement:

intervertebral joints cartilaginous symphysis slight movable

Any abnormal increase in the anterior concavity (or posterior convexity) of the thoracic curve

kyphosis

The thoracic and pelvic curves are concave anteriorly and are called ________________________________

kyphotic curves (primary curves)

Broad, flat, and directed posteriorly and medially from the pedicles

laminae

The _____________________________ of the axis are broad and thick

laminae

The __________________________________ of the typical cervical vertebra are narrow and thin

laminae

The ________________________ of the thoracic vertebrae are broad and thick, and they overlap the subjacent lamina and the __________________________ are long

laminae spinous processes

The concavities on the upper surface of the pedicles of the first sacral segment and the corresponding concavities on the lower surface of the pedicles of the last lumbar segment form the _________________________________________

last pair of intervertebral foramina

The zygapophyseal facet joints of the second through seventh cervical vertebrae are clearly shown in what projection

lateral

What projection is necessary to show the cervical zygapophyseal joints

lateral

The vertebral column is held together by ___________________________ Why is it jointed and curved?

ligaments so that is has considerable, flexibility and resilience

Any abnormal increase in the anterior convexity (or posterior concavity) of the lumbar or cervical curve

lordosis

The cervical and lumbar curves, which are convex anteriorly, are called ___________________________

lordotic curves (secondary curves)

Inferior thoracic bodies resemble bodies of which vertebrae?

lumbar

At their posterior surface, these vertebrae are flattened anteriorly to posteriorly, and they are transversely concave and their anterior and lateral surfaces are concave from top to bottom

lumbar vertebrae

The bodies of these vertebrae are bean-shaped and increase in size from the first to the fifth vertebra in this region, they are deeper anteriorly than posteriorly, and their superior and inferior surfaces are flattened or slightly concave

lumbar vertebrae

The five vertebrae occupying the region of the loin are

lumbar vertebrae

The lumbar and pelvic curves join at an obtuse angle termed the ___________________________________

lumbosacral angle

The superior surface of the base of the sacrum corresponds in size and shape to the inferior surface of the last lumbar segment, with which it articulates to form the _______________________________

lumbosacral junction

A smoothly rounded projection on the back of each superior articular process of the lumbar vertebrae

mammillary process

Is the sacrum longer, narrower, more evenly curved, and more vertical in men or women?

men

Central mass of soft, pulpy, semigelatinous material of the intervertebral disks

nucleus pulposus

In what direction does the tranverse processes of the thoracic vertebrae project?

obliquely, laterally, and posteriorly

Area of lamina between the two articular processes

pars interarticularis

Short, thick processes that project posteriorly, one from each other, from the superior and lateral parts of the posterior surface of the vertebral body

pedicles

The __________________________________ of the typical cervical vertebra project laterally and posteriorly from the body, and their superior and inferior vertebral notches are nearly equal in depth

pedicles

The _________________________________ of the lumbar vertebrae are strong and are directed posteriorly and the ________________________ are thick

pedicles laminae

Each of the anterior and posterior walls of the sacral canal is perforated by four pairs of ___________________________________________ for passage of the sacral nerves and blood vessels

pelvic sacral foramina

Bodies of the typical (third through ninth) thoracic vertebrae are deeper posteriorly or anteriorly and their posterior surface is ____________________________ from side to side

posteriorly concave

The thoracic and pelvic curves are called ____________________________________ because they are present at birth

primary curves

The upper limbs are supported indirectly via the _________________, which articulate with the sternum, and the sternum articulates with the ____________________________

ribs shoulder girdle

A slight lateral curvature is sometimes present in the upper thoracic region and is to the _______________ in right-handed persons and to the ________________ left-handed persons, and because of this the lateral curvature of the vertebral column is believed to be the result of _____________________ and to be influenced by ___________________________

right left muscle action occupation

3 foramina of the cervical vertebrae:

right and left transverse foramina vertebral foramina

Located directly behind the bodies of the sacral segments; is the continuation of the vertebral canal and is contained within the bone and transmits the sacral nerves

sacral canal

Two processes that project inferiorly from the posterolateral aspect of the last sacral segment to joint the coccygeal cornua

sacral cornua

Prominent ridge at the superior anterior margin of the base of the sacrum

sacral promontory

The five vertebrae located in the pelvic region

sacral vertebrae

The vertebral column articulates with each hip bone at the ___________________________, this articulation supports the vertebral column and transmits the weight of the trunk through the hip joints and to the lower limbs.

sacroiliac joints

Curved, triangular bone formed by fusion of the five sacral segments; it is wedged between the iliac bones of the pelvis

sacrum

The sacral segments usually fuse into one bone called the ____________________, and the coccygeal segments, referred to as the ________________________ also fuse into one bone

sacrum coccyx

An abnormal curvature of the spine, this condition causes the vertebrae to rotate toward the concavity

scoliosis

congenital defect of the vertebral column in which the laminae fail to unite posteriorly at the midline

spina bifida

The _____________________________ of the vertebrae projects posteriorly and inferiorly from the junction of the laminae in the posterior midline

spinous process

The ________________________________ of the axis is horizontal in position

spinous process

From the fifth to the ninth vertebrae, the _____________________________ project sharply inferiorly and overlap each other, but they are less vertical above and below this region

spinous processes

The _______________________________ of the lumbar vertebrae are large, thick, and blunt, and they have an almost horizontal projection posteriorly; the palpable tip of each of these corresponds in position with the interspace below the vertebra from which it projects

spinous processes

The __________________________________ of the typical cervical vertebra are short, have double-pointed (bifid) tips, and are directed posteriorly and slightly inferiorly; their palpable tips lie at the level of the interspace below the body of the vertebra from which they arise

spinous processes

Spondylolysis occurring on one or both sides of the vertebra; is characterized by the anterior displacement of one vertebra over another, generally the fifth lumbar over the sacrum; most exclusively involves the lumbar spine

spondylolisthesis

Is an acquired bony defect occurring in the pars interarticularis

spondylolysis

The ________________________________ and ___________________________ of the typical cervical vertebra are located posterior to the transverse processes at the point where the pedicles and laminae unite.

superior and inferior articular processes

Each _______________________________________ has an articular facet on its posterior surface

superior articular process

Located at each side of the dens on the superior surface of the vertebral body; they are adapted to join with the inferior articular processes of the atlas

superior articular processes

The ________________________________________ of the first sacral segment articulate with the inferior articular processes of the last lumbar vertebra to form the last pair of zygapophyseal joints

superior articular processes

What kind of facets do the ninth thoracic vertebrae have?

superior demifacet

Portion of the first sacral segment that remains distinct and resembles the vertebrae of the lumbar region

superior portion

The _________________________________ of each lateral mass of the atlas lie in a horizontal plane , are large and deeply concave, and are shaped to articulate with the occipital condyles of the occipital bone of the cranium

superior processes

Function of the pedicles and laminae of the vertebral arch:

support 4 articular processes, 2 transverse processes, and 1 spinous process

The succeeding 12 bones that lie in the dorsal, or posterior, portion of the thorax

thoracic vertebrae

Ligament that divides the ring formed by the arches of the atlas into anterior and posterior portions

transverse atlantal ligament

The _________________________________ of the vertebrae project laterally and slightly posteriorly from the junction of the pedicles and laminae

transverse processes

The ____________________________________ of the typical cervical vertebra arise partly from the sides of the body and partly from the vertebral arch; they are short and wide, are perforated by the transverse foramina for transmission of the vertebral artery and vein, and present a deep concavity on their upper surfaces for passage of the spinal nerves

transverse processes

The ______________________________________ of lumbar vertebrae are smaller than those of thoracic vertebrae; the superior three pairs are directed almost exactly laterally, whereas the inferior two pairs are inclined slightly superiorly

transverse processes

The _________________________________________ of the atlas are longer than those of the other cervical vertebrae , and they project laterally and slightly inferiorly from the lateral masses

transverse processes

What causes HNP of cervical spine?

trauma or degeneration

Shape of the bodies of the typical (third through ninth) thoracic vertebrae?

triangular

The superior four pairs of foramina are shown with the pt in what position, but the last pair requires what?

true lateral slight obliquity of the body

The 24 vertebral segments in the upper three regions remain distinct throughout life and are termend the __________________________________

true or moveable vertebrae

Cervical vertebrae C3-C6 have a small, transversely located, oblong body with slightly elongated anteroinferior borders

typical cervical vertebrae

Seventh cervical vertebra (C7), has a long, prominent spinous process that projects almost horizontally to the posterior and it is called the _____________________________

vertebra prominens

The vertebral column is composed of small segments of bone called _______________________

vertebrae

Posterior ringlike portion of the vertebra

vertebral arch

In the articulated column, the vertebral foramina form the _____________________________

vertebral canal

Space enclosed by the vertebral body and arch

vertebral foramen

Concave superior and inferior surfaces of the pedicles or roots form the __________________________________

vertebral notches

The body of the first thoracic vertebra presents a _________________________________ near its superior border for articulation with the head of the first rib and presents a _______________________________________ on its inferior border for articulation with the head of the second rib

whole costal facet demifacet (half-facet)

The tenth, eleventh, and twelfth thoracic vertebral bodies have a single __________________________________ at the superior margin for articulation with the eleventh and twelfth ribs

whole facet

Articulations between the articular processes of the vertebral arches Type: Movement:

zygapophyseal joints synovial gliding free movable

The articulations between the articular processes of the vertebral arches are the synovial intervertebral joints, referred to as ________________________________________________

zygapophyseal joints (interarticular facet joints)