axial skeleton. vertebral column/ spine supports the skull /transfers weight structure: 26 irregular...
TRANSCRIPT
Axial Skeleton
Vertebral Column/ Spinesupports the skull /transfers weight
• Structure:• 26 irregular bones• (33 pre-birth)
• 7 cervical• 12 thoracic• 5 lumbar• 1 sacrum• 1coccyx
• Intervertebral foramen-Between each vertebraeFor spinal nerves
Intervertebral discs-Cushion/absorbs shockProvides flexibilityHardens with age
Herniated Disc
• When the annulus wall weakens, the disc will press against the spinal nerve = PAIN
curvatures• Primary curvature-• What you are born with• Posterior = Convex• Secondary curvature-• What develops• Cervical becomes-
posterior concave when baby lifts head
• Lumbar becomes posterior concave when baby walks
Abnormal Curvatures• Scoliosis- abnormal side
to side• Kyphosis-Exaggerated
posterior curvature of thoracic vertebrae- osteoporosis
• Lordosis-exaggerated posterior curve of lumbar
• Pregnancy, pot belly
Typical Vertebrae
• Body- weight bearing anterior
• Vertebral Arch- join the laminae and pedicles posterior
• Vertebral Foramen- canal that spinal cord passes
• Transverse Process- 2 lateral projections from the arch
Typ ical verteb rae
• Spinal Process- single projection from posterior arch
• Superior and Inferior Articular Processes- paired projections lateral to the foramen allows the vertebrae to join each other
Cervical Vertebrae - neckC1 - ATLAS
• No body • receives the
occipital condyles • Allows the “yes”
nod
Cervical vertebrae
C-2 - AXIS
• Has an upright pivot called dens or odontoid process
• Allows rotation- “no”
Cervical vertebraeC-3 to C- 7
• Small• Short bifid spinous process• Transverse processes contain
foramen for arteries
Thoracic VertebraeT1 – T12
• Larger heart shaped body• Long spinous
process-points downward• 2 costal facets on
either side for ribs
Thoracic Vertebrae
Lumbar vertebraeL1 – L5
•Massive body• Hatchet like
spinous process• Takes most
stress
Sacrum 5 fused vertebrae• Posterior Pelvis• wing like• Lateral
articulation with hip• Medial Sacral
Crest- posterior fused spinous processes
Sacrum
• Sacral foramina- lateral to crest• Sacral Canal-
down the center• Sacral Hiatus-
inferior opening
Coccyx 3-5 fused vertebrae
• tailbone
Bony Thorax
• Ribs• Sternum• Thoracic
vertebrae
Sternum
• Manubrium- jugular notch
• Body- sternal angle (3rd rib)
• Xiphoid Process- small point at bottom
Xiphoid
• The Xiphoid process can cause damage because of the location of the liver
Costal Cartilage
• The costal cartilage attaches the ribs to the sternum-hyaline cartilage
Ribs- 12 pairs• True ribs-are
connected to the sternum- vertebrosternal # 1-7
• Posterior – attached to thoracic vertebrae 1-7
• Anterior- attached to sternum
• False Ribs- are not connected directly to the sternum
• Ribs 8-10 are called false
• Ribs 8-10 are called vertebrochondral
• Posterior- attaches to vertebrae
• Anterior- attaches to cartilage
• Floating Ribs- ribs 11 & 12
• They are not connected in the anterior, only the posterior
• Posterior- vertebrae• Anterior- nothing
Ribs- flat bones
• Head- meets with the body of the thoracic vertebrae
• Neck- meets with the transverse process of the thoracic vertebrae
• Shaft- angles downward