Health Occupations

Skeletal System – Unit 2

Spinal Column

Made up of 26 bones, divided into 5 parts Function

– Protect spinal cord– Provide support for head & neck

Curvature gives strength & flexibility Each bone is called vertebrae Intervertebral discs

– Pads of cartilage separating the vertebrae– Act as shock absorbers– Allow bending & twisting

Vertebrae

Bone is called the vertebral body 5 parts

– Cervical – neck, 7– Thoracic – chest, 12– Lumbar – waist, 5– Sacrum – back of pelvic girdle, 1– Coccyx – tailbone, 1

Cervical Vertebrae

Thoracic Vertebrae

Lumbar Vertebrae

Sacrum

Coccyx

C1 - Atlas

C2 - Axis

Vertebral Body

Intervertebral Disk

Thorax Ribs, Sternum, Vertebral bones

– Protect heart & lungs Ribs

– 12 pair, called COSTAE– Attach to thoracic vertebrae on DORSAL surface of

body– Types of ribs

• True ribs – first 7, attach directly to sternum• False ribs – next 3, attach to cartilage of rib above• Floating ribs – last 2, do not attach to front of body

– INTERCOSTAL space –• Area between ribs containing muscles, blood vessels, & nerves

Thorax (cont)

Sternum– Breast bone– 3 parts

• Manubrium – upper part, where clavicles attach• Gladiolous – body, where hands are placed during CPR• Xiphoid process – small piece of cartilage at bottom,

DANGER during CPR

– Ribs attach to sternum with costal cartilage & provide a cage protecting the heart & lungs

True Ribs

False Ribs

Floating Ribs

Sternum - Gladiolus

Xiphoid process

Vertebral column

Pectoral Girdle

Shoulder – made up of clavicles & scapulas Clavicle –

– 2 bones– Collar bones– Attach to manubrium of sternum with ligaments

Scapula– 2 shoulder blades– Provide for attachment of upper arm bones

Bones of the Arm

Humerus – upper arm Radius – lower arm, thumb side Ulna – larger bone of lower arm, little finger

side– Olecranon process – projection on upper end of

ulna, forms elbow Carpals – 8 bones of wrist Metacarpals – 5 bones in palm of hand Phlanges – 14 bones of fingers

Pelvic girdle Made up of 2 os coxae (coxal or hip bones) Joins with sacrum on dorsal side of body at the SACROILIAC

joint Join together on ventral side of body at the SYMPHYSIS

PUBIS 3 parts, fused together

– Ilium– Ischium– Pubis

Acetabula – 2 recessed areas (sockets) for leg bone attachment

Obturator foramen – opening between ishium & pelvis allowing passage of nerves & blood vessels to & from legs

Coccyx

AcetabulumObturator foramen

Symphysis pubis

Pubis

Ischium

Ischial spine

Ilium

SacrumSacroiliacjoint

Legs

Femur – thigh Patella – kneecap Tibia – lower leg, large bone, big toe side Fibula – lower leg, small bone, little toe side Tarsals – 7 bones in ankle Metatarsals – 5 bones in instep of foot Phalanges – 14 bones in toes Calcaneous – heel that is formed by the large

tarsal bone

Parietal

Occipital

Scapula

VerbebraeOlecranonprocess

Ilium

Coccyx

Femur

Calcaneous

MaxillaZygomatic

Mandible Clavicle

SternumRibsXiphoid process

Sacrum

Pubis

IschiumSymphysispubis

PatellaTibiaFibula

TarsalsMetatarsalsPhlanges

UlnaRadiusCarpals

MetacarpalsPhlanges

Obturator foramen

Humerus