Lecture Presentation by Patty Bostwick-Taylor

Florence-Darlington Technical College

Chapter 5

The Skeletal System

© 2015 Pearson Education, Inc.

© 2015 Pearson Education, Inc.

Vertebral Column (Spine)

• Vertebral column provides axial support

– Extends from skull to the pelvis

• 26 single vertebral bones are separated by intervertebral discs

– 7 cervical vertebrae are in the neck

– 12 thoracic vertebrae are in the chest region

– 5 lumbar vertebrae are associated with the lower back

© 2015 Pearson Education, Inc.

Vertebral Column (Spine)

• 9 vertebrae fuse to form two composite bones

– Sacrum formed by the fusion of 5 vertebrae

– Coccyx (tailbone) formed by the fusion of 3 to 5 vertebrae

Figure 5.16 The vertebral column.

1st lumbar vertebra

Intervertebral foramen

Intervertebral disc

Spinous process

Transverse process

1st thoracic vertebra

1st cervical vertebra

(atlas)

2nd cervical vertebra

(axis)

Anterior Posterior

Cervical curvature (concave)

7 vertebrae, C1 – C7

Thoracic curvature (convex)

12 vertebrae, T1 – T12

Lumbar curvature (concave)

5 vertebrae, L1 – L5

Sacral curvature (convex)

5 fused vertebrae

Coccyx

4 fused vertebrae

Figure 5.19 A typical vertebra, superior view.

Lamina Posterior

Vertebral

arch Transverse

process

Spinous

process

Vertebral

foramen

Body

Anterior

Pedicle

Superior

articular

process

and

facet

Figure 5.20a Regional characteristics of vertebrae.

Transverse

process

(a) ATLAS AND AXIS

Posterior

arch

Superior view of axis (C2)

Anterior arch

Superior view of atlas (C1)

Transverse

process

Spinous process

Dens

Body

Facet on

superior

articular

process

Figure 5.20b Regional characteristics of vertebrae.

(b) TYPICAL CERVICAL VERTEBRAE

Right lateral view

Spinous process Facet on

superior

articular

process

Vertebral

foramen

Transverse

process Superior view

Body

Facet on inferior

articular process

Transverse

process

Superior articular

process

Spinous

process

Figure 5.20c Regional characteristics of vertebrae.

(c) THORACIC VERTEBRAE

Right lateral view

Transverse

process

Body

Body

Spinous process

Facet

for rib

Vertebral

foramen

Facet on

transverse

process Spinous

process

Costal facet

for rib

Superior view

process

Facet on

superior

articular

Facet on

superior

articular

process

Figure 5.20d Regional characteristics of vertebrae.

(d) LUMBAR VERTEBRAE

Right lateral view

Transverse

process

Vertebral

foramen

Facet on

superior

articular

process Body

Body Superior

articular

process

Spinous

process Facet on inferior

articular process

Superior view

Spinous process

Figure 5.21 Sacrum and coccyx, posterior view.

Ala

Sacrum

Coccyx Sacral

hiatus

Posterior

sacral

foramina

Median

sacral

crest

Body

Auricular

surface

Superior

articular

process Sacral

canal

© 2015 Pearson Education, Inc.

The Bony Thorax

• Forms a cage to protect major organs

• Consists of three parts

1. Sternum

2. Ribs

• True ribs (pairs 1–7)

• False ribs (pairs 8–12)

• Floating ribs (pairs 11–12)

3. Thoracic vertebrae

Figure 5.22a The bony thorax (thoracic cage).

Clavicular notch

True

ribs

(1–7)

False

ribs

(8–12)

(a)

Floating

ribs (11, 12)

L1

vertebra Costal cartilage

Intercostal

spaces

T1 vertebra

Jugular notch

Manubrium

Sternal angle

Body

Xiphisternal

joint

Xiphoid

process

Sternum