Anatomy Topic 17: Vertebral Column

number of total vertebrae

24

number of cervical vertebra (in neck)

7 (C1-C7)

number of thoracic vertebrae (in middle of spine)

12 (T1-T12)

number of lumbar vertebrae (lower back)

5 (L1-L5)

total bones in the vertebral column

33

number of sacrum bones

5

number of coccyx bones

3-5

spine curves you have from birth

thoracic and sacral (one big curve)

spine curves you develop with age

cervical and lumbar (develops as you walk)

normal curve

looks like a shallow s

cervical lordosis

the natural inward curve of the neck

thoracic kyphosis

the outward (posteriorly projected) curve of the thoracic spine

exaggerated thoracic kyphosis

hunch back, curve is more posterior projecting than we would like

lumbar lordosis

natural inward curve of the lower spine

exaggerated lumbar lordosis

hips rocked forward, curved too much in the lumbar region

lateral deviation

scoliosis, spine curves laterally, deviating from the natural relatively straight spine

sagittal plane spine issues

• thoracic kyphosis

• lumbar lordosis

• cervical lordosis

frontal plane spine issues

• scoliosis (lateral deviation)

C1 and C2 are special because

C1: no body where the skull sits (atlas because it holds up the skull)

C2: lets you shake your head no

intervertebral disc joint type

cartilaginous joint

annulus fibrosus

outer ring of intervertebral disc

starts at C2 and goes to L5

separates vertebrae and makes room for nerve roots, transmits loads; made of elastic and reticular fibers, 75% water

nucleus pulposus

center of intervertebral disc

herniated disc

when annulus fibrosus protrudes posteriorly or laterally and bulges into the nerves that run through the spine

anterior longitudinal ligament

spans vertically from body to body on the anterior side

prevents hyperextension

posterior longitudinal ligament

runs vertical from body to body on the posterior spine

prevents flexion

supraspinous ligament

runs from T1-sacrum (lower back and thoracic region)

prevents flexion

ligamentum nuchae

runs from C1-C7 in neck

holds head up

prevents flexion

interspinous ligament

between spine (between the spinous processes)

stretches with rotation and flexion

intertransverse (costotransverse) ligament

connects transverse processes from one to the next

handles lateral flexion and some rotation