Anatomy - Chapter 7 (Axial)

axial skeleton

attaches to limbs of appendicular skeleton

axial skeleton functions

• protects heart + lungs

• respiratory movement (ribs expand so we can breathe)

• anchor

sutures

joints between skull bones

coronal suture

attaches frontal to parietal

squamous suture

attaches temporal to parietal

saggital suture

attaches parietal bones

lambdoid suture

attaches occipital to parietal

auditory ossicles

• turn vibrations into what we can hear

• 3 tiny bones in middle ear

• transfer sound from eardrum to middle ear

petrous

• stone-like bone

• on temporal bone

• hard to protect our hearing

sinuses

• air filled chambers

• lighten bone

• allow voice to resonate

infant skull

• fusion is not complete at birth

  • 2 frontal bones

  • 4 occipital bones

fontanelles

• allow for growth + get baby through birth canal

• cartilage is replaced with sutures

• all fontanelles are replaced by age 5 (brain is done growing)

anterior fontanelles

• soft spot on top of head

• there until 2 years old

• covers major blood vessel

craniostenosis

permature closing of fontanelles

plagiocephaly

• flattening of head due to pressure

• use helmet

vertebral column

• cervical: 7 bones

• throacic: 12 bones

• lumbar: 5 bones

primary curves

• develop before birth

• thoracic + sacral

thoracic curve

gives space for heart + lungs

sacral curve

gives space for reproductive organs

secondary curves

• develop after birth

• cervical + lumbar

cervical curve

• balances head

• develops when baby lifts its head

lumbar curve

• balances trunk

• develops when baby learns to stand

kyphosis

• thoracic curve exaggeration

• hump back

• from osteoporosis

lordosis

• lumbar curve exaggeration

• in pregnancy + low muscle tone

scoliosis

• abnormal lateral curve

• growth spurts in kids

thoracic cavity

• thoracic vertebrae

• ribs + sternum (make rib cage)

thoracic cage

• attaches for muscles in

  • breathing

  • position on vertebral column

  • moving upper limbs

• mobility in upper limbs

• stability in lower limbs

movement of ribs

• rib is like a bucket handle

  • Exhale: pushing down moves rib inward

  • Inhale: pulling up moves rib outward

• movement affects width, depth + volume in rib cage