Vertebral Column Learning Goals 1- Name the regions of the vertebral column, and number of vertebrae in each segment 2- Identify the distinguishing characteristics of vertebrae from each spinal column segment

Adult Vertebral Column 26 vertebrae 24 individual vertebrae Sacrum – 5 fused vertebrae Coccyx – 4 fused vertebrae (7) Seven cervical vertebrae (12)Twelve thoracic vertebrae (5) Five lumbar vertebrae

Adult Vertebral Column strong, flexible rod average male = 71 cm (28 inches) average female – 61 cm (24 inches) capable of moving anteriorly posteriorly laterally also rotation supports the head encloses and protects the spinal cord allows for the exit of 31 pairs of spinal nerves – through intervertebral foramina

Spinal Curvature Four curvatures: increase the strength of the column Thoracic (primary) – forms fetally and retain the curve of the fetus Sacral (primary) – forms fetally and retain the curve of the fetus Cervical (secondary) – forms when the baby holds its head erect Lumbar (secondary) – forms upon walking

Vertebral Column   

Adult Vertebral Column vertebrae separated by intervertebral discs discs of fibrocartilage made up of an outer ring and a softer inner region found between C1 and C2 and all the way down to between L5 and the sacrum form the joints of the vertebral column absorb shock – flatten, broaden and bulge outward weakening in the outer ring can allow the herniation of the inner material

Every vertebrae has the following: 1. body – weight bearing part of the vertebra separated by the discs 2. vertebral arch – surrounds the spinal cord surrounds a hole called a vertebral foramen 3. processes – seven of them 1. Spinous (1) – muscle attachment 2. Transverse (2) – muscle attachment 3. Superior articular (2) – forms joint with upper vertebra 4. Inferior articular (2) – forms joint with lower vertebra Cervical Vertebra

Cervical Vertebrae Atlas – 1st; supports head Axis – 2nd; pivots to turn head transverse foramina bifid spinous processes vertebral prominens – useful landmark

Vertebral Column Study Guide

Thoracic Vertebrae long spinous processes rib facets

Thoracic Vertebrae

Thoracic Vertebrae

Thoracic Vertebra Lumbar

Lumbar Vertebrae large bodies thick, short spinous processes

Fused Vertebrae: The sacrum & coccyx Sacrum - Union of 5 vertebrae (S1 - S5) – completely fused by age 30 median sacral crest = spinous processes sacral ala = fused transverse processes sacral canal ends at sacral hiatus Coccyx = Union of 4 vertebrae (Co1 - Co4) – completely fused by age 30

Coccyx