A&p Ch 7 Part 2

Front 1

Vertebral Column function

Back 1

• Transmits weight of trunk to lower limbs

• Surrounds and protects spinal cord

Front 2

Bones of Vertebral Column # of

Back 2

• Flexible curved structure containing 26 irregular bones (vertebrae) (33 non-adult = unfused)

– Cervical vertebrae (7)

– Thoracic vertebrae 12

– Lumbar vertebrae (5

– Sacrum

– Coccyx

Front 3

Cervical vertebrae

Back 3

(7)—vertebrae of neck

Front 4

– Thoracic vertebrae

Back 4

12)—vertebrae of thoracic cage

Front 5

Lumbar vertebrae

Back 5

(5)—vertebrae of lower back

Front 6

Sacrum

Back 6

—bone inferior to lumbar vertebrae

Front 7

– Coccyx

Back 7

—terminus of vertebral column

Front 8

Vertebral Column: Curvatures

Back 8

• Increase resilience and flexibility of spine

– Cervical and lumbar curvatures

• Concave posteriorly

– Thoracic and sacral curvatures

• Convex posteriorly

Front 9

Scoliosis

Back 9

- abnormal lateral curve

Front 10

– Kyphosis

Back 10

(hunchback) – exaggerated thoracic curvature

Front 11

– Lordosis

Back 11

(swayback) – accentuated lumbar curvature

Front 12

Intervertebral Discs function and components

Back 12

• Fibrocartilage intervertebral discs act as

shock absorbers & provide flexibility

• Cushionlike pad composed of two parts

1. Nucleus pulposus:

2. Anulus fibrosus:

Front 13

Nucleus pulposus

Back 13

: inner gelatinous nucleus that gives the disc its elasticity and compressibility

Front 14

Anulus fibrosus

Back 14

: outer collar composed of collagen and fibrocartilage

Front 15

General Structure of Vertebrae

• With the exceptions of C1 and C2, all have:

Back 15

– Body

– 7 processes

• Two transverse processes

• Two superior & two inferior articular processes

• Spinous process

– Vertebral arch

Front 16

Function of vertebral body

Back 16

weight bearing part

Front 17

Vertebral foramen

Back 17

Body with vertebral arch forms vertebral

foramen passageway for spinal cord

Front 18

Atlas

Back 18

(C1)

– No body or spinous process

– Superior surfaces of lateral masses articulate

with the occipital condyles

Front 19

Axis

Back 19

(C2)

– Dens projects superiorly into the anterior arch

of atlas

– Dens is a pivot for the rotation of atlas “no”

– Trauma can drive dens into medulla oblongata

Front 20

Sacrum

Back 20

– 5 fused vertebrae (S1–S5)

– Forms posterior wall of pelvis

Front 21

Sacrum articulates with:

Back 21

Articulates with L5 superiorly,

and with auricular surfaces of hip bones, forming

sacroiliac joints

Front 22

Coccyx

Back 22

– Tailbone

– 3–5 fused vertebrae

Front 23

Coccyx articulates with:

Back 23

superiorly with sacrum

Front 24

The atlas vertebral articulates superiorly

with the:

Back 24

occipital bone/occipital condoyle