Vertebral Column

Question 1

The Vertebral column has how many vertebrae?

Answer 1

-24 individual vertebrae

Question 2

How many regions in the spine?

Answer 2

• Cervical
• Thoracic
• Lumbar
• Sacral
• Coccygeal

Question 3

Cervical Lordosis

Answer 3

• Cervical ( top portion of the spine)
• 7 vertebrae
• C1 and C2 may be fused the occipital bone of the skull
• normally curved with the convexity facing anteriorly,

Question 4

Thoracic Kyphosis

Answer 4

• 12 vertbrae (middle)

- curved facing posteriorly

Question 5

Lumbar lordosis

Answer 5

• 5 vertebrae (near bottom)
• L5 maybe fused to the sacrum
• convexity faces anteriorly

Question 6

Sacral

Answer 6

-Five sacral vertebrae are fused to form the sacrum

S1 maybe free (transitional vertebrae

Question 7

Coccygeal

Answer 7

–Four coccygeal vertebrae form the coccyx

Question 8

The Curves of the spine form when?

Answer 8

• the curves of the spine of the spine form secondarly to the development of postural reflexes about three months after birth.

Question 9

Motion segement

Answer 9

• Each pair of individual, nonfused vertebrae, with intervening intervertebral disc, facet joints, and ligaments, constitute a motion segement, the basic movable unit of the intervebral column

Question 10

Motion Segement is made up of how many joints?

Answer 10

• Three joints (except C1 & C2)
• a partly moveable intervertebral disc anteriorly, and a pair of gliding synovial facet (zygapophyseal) joint posteriorly

Question 11

intervertral disc

Answer 11

• -is a martly movable fibrocartilaginous joint between two vertebrae consisting of (1) the load bearing annulus fibrosus attached to the vertebral bodies above and below, and the mosre central nucleus pulposus; it transfers the load imposed on it to the annulus.
• the discs amke possible movement betweeen the vertebral bodies.

Question 12

vertebral formina

Answer 12

-longtitudal series of vertebral formina form the spinal (or neural or vertebral) canal, transmitting the spinal cord and related coverings, vessels, and nerve roots

Question 13

annulus fibrosus

Answer 13

• layers of concentric, interwoven collagenous fibers integrated with cartilage cells

Question 14

nucleus pulposus

Answer 14

• a mass of thin, degenerated collagen and proteoglycans in water

Question 15

Cervical vertebrae

Answer 15

• support and move the head and neck, supported by intervertebral discs between C2 and T1

Question 16

C1 and the occiptial bone

Answer 16

-The ring shape atlas of (C1) has no body; thus, there are no weight-bearing discs between the occiptal bone (occiput) of the the skull and C1, and between C1 and C2(the axis)

Question 17

How is the weight of the head transfered?

Answer 17

• head weight is tranferred to C3 by the large articular processes and facets of C1 and C2.

Question 18

Atlantoocipital joints

Answer 18

• in conjunction witht he C3 and -C7 facet joints permit a remarkable degree of flexion/ extension

Question 19

Head movement?

Answer 19

• the dens of C2 projects into anterior part of the C1 ring, forming a pivot joint and enabling the head and C1 to rotate up to 80 degree. such rotation capacity is permitted by the relatively horizontal orientation of the cervical facets.
• C3-C6 vertbrae are similar

Question 20

C7

Answer 20

• prominant spinous process easily palpated. the anteriorly directed cervical curve( convex anteriorly) and the extensive paracervical musculature generally prelude palpation of the other cervical spinous process.

Question 21

vertebral arteries

Answer 21

vertebral arteries arise from the subclavian arties and reach the brain stem, by way of the formina of the transverse process of the upper six cervical vertebrae, and make an S-turn ino the foramen magnum. these vessels are subject to stretching injuries with extreme cervical rotation of the hyperextened neck.

Question 22

What does the cervical vertebral canal do?

Answer 22

• it conducts the cervical spinal cord and its coverings.

Question 23

what are the most mobile of the cervical region?

Answer 23

• The C4-C5 and C5-C6 are the most mobile of the cervical region and are partiularly prone to disc and facet degeneration with aging.

Question 24

thoracic vertbrae

Answer 24

• 12
• characerized by long slendor spinous processes, heart shaped bodies, nearly vertically oriented facets, and eleven interverbral discs, support the chest and aticulate with ribs bilaterally. in general, each rib forms a synovial joint with two demifacets on the bodies of adjacent vertebra. Variations of these costovertebral joints are seen with T1, T11 and T12. The existance of the ribs in the thoracic region contributes to the relatively reduced range of motion in this part of the vertebral column

Question 25

Lumbar vertebrae

Answer 25

• these five vertebrae are the most massive of all the individual vertebrae. theri thick processes secure the attachements of numerous ligaments and muscle tendons.
• significant flexion and extension of the lumbar and lumbosacral motion segments, particularly at L4-L5 and L5- S1, are possible.
• At about L1 the spinal cord terminates and cauda equina begins

Question 26

cauda equina

Answer 26

• bundle os lumbar, sacral, and coccygeal nerve roots

Question 27

lumbar intervertebral formina

Answer 27

• are large; tranmitting nerve roots/sheaths take up only about 50% of the forminal volume.
• occasionly L5 vertebra is partially or compleelty fused to the sacrum.- leaving only 4 vertebrae
• S1 vertebra may partially or wholly fuse to L5, resulting in essentially 6 lumbar verte brae

Question 28

planes of the articular facets

Answer 28

-the planes of the articular facets strongly influence, but do not complelety determine, the direction and degree of motion-segment movement.

Question 29

cervical facets

Answer 29

• the plane of the cervical facets is angled off the horizontal plane about 30 degree, giving the neck considerable freedom of motion, especially in rotation.

Question 30

thoracic facets

Answer 30

• the thoracic facets are arranged more vertically in the coronal plane and are virtually non-weight-baring. the range of motion here is significantly limited in all planes, especially rotation.

Question 31

lumbar facets

Answer 31

• the plane of the lumbar facets is largely sagittal, resisting rotation of the lumber spine. The L4-L5 facet joints permit the greatest degree of lumbar motion in flexion /extension. the lower lumber facets, oriented in the saggital planes as they are, are prone to reorienting toward the coronal plane under continued stress.
• this change makes it easier for L4-L5 and L5-S1 to experience disc trama by allowing more rottion than normal when rotatting the torso let or right whiel bearing loads.

Question 32

sacrum

Answer 32

• consists of fused vertebrae: the intervertbral discs here are largely replaced by bone. the dura-lined sacral canal contians the terminal sac of the dura mater that ends at S2.
• The sacral nerve roots continue inferiorly as the cauda equina, transmiting their respective sacral intervertebral formina. This sac is relatively safe for injection into or withdrawal of cerebrospinal fluid.

Question 33

what forms the sacroilliac joint?

Answer 33

• the sacrum joins with the ilium of the hip bone at the auricular surface, forming the sacroiliac joint.

Question 34

What contributes to the wieght bearing of the hips?

Answer 34

• The sacrum and ilia of the hip bones form an arch for the transmission and distribution of weight-bearing forces from the spine to the heads of the femora.

Question 35

Coccyx

Answer 35

• the tail bone
• consists of 2-4 tiny fused, rudimentary vertebrae.
• rare occasion there may be more coccygeal vertebrae
• falls are generally on of the more unpleasant experiences