Skeleton System: Vertebral Column also inculding Sacrum and Coccyx

Vertebral Column

Transmits weight of trunk to lower limbs

Surrounds and protects spinal cord

Flexible curved structure containing 26 vertebrae and 5 MAJOR REGIONS

5 major regions of vertebral column

Cervical vertebrae (7) - vertebrae of neck

Thoracic vertebrae - vertebrae of thoracic cage

Sacrum - Bone INFERIOR to lumbar vertebrae

Coccyx - terminus of vertebral column

Intervertebral discs

Cushion like pad composed of 2 parts:

1. Nucleus pulposus - INNER gelatinous nucleus and gives the disc elasticity/compressibility

2. Anulus fibrosus - OUTER collar comprised of collagen fibrocartilage

General structure of vertebrae

Body

Vertebral arch

Vertebral foramen

Intervertebral foramen

Spinous and transverse processes

Body of vertebrae

Anterior weight bearing region

Vertebral arch

Composed of pedicles and laminae

Vertebral foramen

Hole beneath arch that HOLDS spinal cord

Intervertebral Foramen

Arterial openings between adjacent vertebrae for spinal nerves

Spinous and transverse processes of vertebrae

Attaches to vertebral muscles

TPs articulate with ribs on thoracic vertebrae

Cervical vertebrae

C1 (Atlas) and C2 (Axis)

ONLY cervical vertebrae have 3 holes

3 holes of cervical vertebrae

1 vertebral foramen

2 transverse foramina

C7 is vertebra prominens

Thoracic vertebrae

T1 to T2 is connected to RIBS

Costal facets have articulations that point to ribs

Lumbar vertebrae

L1 to L5

Large body

Large flat hatchet-shaped spinous processes

Sacrum

5 fused vertebrae (S1-S5)

Forms posterior wall of PELVIS

Articulates with L5 SUPERIORLY

Articulated with HIP BONES LATERALLY (sacroiliac joints)

Coccyx

Tailbone

3-5 fused vertebrae