1. The Vertebral Column

2. Extends from skull (supports the skull) to the pelvis (distributes weight to lower limbs) Five sections: cervical, thoracic, lumbar, sacrum, coccyx Born with 33 vertebrae, but nine fuse into two bones (sacrum and coccyx) Vertebrae separated by intervertebral discs

3. Body/Centrum – disc-like part facing anteriorly Vertebral arch – formed by joining of all posterior extensions of vertebra Vertebral foramen – opening which spinal cord passes Transverse processes – two lateral projections from arch Spinous process – projection from posterior of arch Articular processes – superior and inferior projections lateral to foramen that articulate with above vertebra

5. 7 vertebrae (identified as C 1 to C 7 ) –First two vertebrae are Atlas (C 1 ) and Axis (C 2 ) Allow for the movement/rotation of skull Do not have a body Atlas articulates with the occipital condyles of the skull –C 3 through C 7 are remaining cervical vertebrae Smallest vertebrae Contain transverse foramen Spinous processes usually split in middle

7. 12 vertebrae (identified as T 1 to T 12 ) –Connected with ribs –Typical shape, slightly modified for ribs Includes costal facets to articulate with ribs in posterior Spinous process long, pointed down

9. 5 vertebrae (identified as L 1 to L 5 ) –Bulkier shape –Hatchet-shaped spinous processes –Receives most of stress on vertebral column

11. Sacrum is inferior to the L 5 vertebra and superior to the coccyx –Formed from the fusion of five vertebrae –Alae are winglike projections that articulate laterally with the hip bones –Forms posterior wall of pelvis –Includes median sacral crest and dorsal sacral foramina Coccyx is inferior to sacrum –Formed from fusion of three to five tiny vertebrae –Commonly called the “tailbone”