INTRODUCTION TO THE SKELETAL SYSTEM

The Axial Skeleton (Part 1)

OVERVIEW Histology of Bone Tissue Bone Function and Structure Bone Growth & Development Joints The Axial Skeleton The Pectoral Girdle The Upper Limbs The Pelvic Girdle The Lower Limbs

THE AXIAL SKELETON 22 bones in skull 6 in middle ears 1 hyoid bone 26 in vertebral column 25 in thoracic cage

80 Bones in Axial Skeleton

THE AXIAL SKELETON Function:

Axial skeleton supports and protects organs of head, neck and trunk

THE SKELETON (AXIAL SKELETON)+ skull

(cranium and facial bones)

+ hyoid bone (anchors tongue and muscles associated with swallowing)

+ vertebral column(vertebrae and disks)

+ thoracic cage(ribs and sternum)

THE SKULL Cranial bones (or cranium):

Structure: 8 sutured bones in cranium

Functions: encases brain attachments for muscles (mostly

neck) sinuses

THE SKULL Facial bones (anterior aspect of skull):

Structure: 13 sutured bones, 1 mandible

Functions: framework of face cavities for sense organs of sight, taste

and smell openings for passage of air and food hold teeth Attachments for muscles of face

NOW…LET’S TALK TEETH… “Your teeth are also considered part of your skeletal system, but

they are not counted as bones. Your teeth are made of enamel and dentin. Enamel is the strongest substance in your body.”

http://hes.ucfsd.org/gclaypo/skelweb/skel01.html

“When discussing the human skeletal system it is important to include

the teeth. Hillendale Health explains that even though the teeth are not considered bones, they are part of the framework that forms the human skeleton. It is also important to note that the enamel that forms the teeth is the strongest substance within the body.

http://www.ehow.com/about_5099016_introduction-skeletal-system.html

SKULL (LATERAL VIEW)

SKULL (LATERAL VIEW)

INFANT SKULL (SUPERIOR VIEW)

SKULL (INFERIOR VIEW)

SKULL (POSTERIOR VIEW)

SINUSESFrontal Sinus

Ethmoid SinusSphenoid Sinus

Maxillary Sinus

“Sinus Headaches”Location of pain: Depends on which sinuses are affected.If frontal sinuses are affected, then pain will be felt just above the eyebrows.If ethmoid sinuses are affected, then pain will be felt between the eyes.If maxillary sinuses are affected, then pain will be felt in the cheekbones region.

BONES OF THE MIDDLE EAR (OSSICLES) Structure: A-Malleus (hammer) B-Incus (anvil) C-Stapes (stirrup) (smallest bone of

the body)

Function: Changes acoustical energy (sound) into mechanical energy

HYOID Structure: see below Function:

anchors tongue and muscles associated with swallowing

THE AXIAL SKELETON

Cervical Vertebrae (7)

Thoracic Vertebrae (12)

Lumbar Vertberae (5)SacrumCoccyx

THE AXIAL SKELETON

SternumTrue Ribs (7)False Ribs (3)Floating Ribs (2)

SUMMARY Histology of Bone Tissue Bone Function and Structure Bone Growth & Development Joints The Axial Skeleton The Pectoral Girdle The Upper Limbs The Pelvic Girdle The Lower Limbs