VI Surface Features of Bones
A Depressions, holes, & extensions that serve a certain function
1 Form joints
2 Site for muscle attachment
3 Passage way for nerves and blood vessels
B Types of holes and depressions
1 Foramen: hole in a bone ex. foramen magnum
2 Fossa: depression usually to form a joint. ex. olecronon fossa
3 Meatus: tubelike opening. ex. auditory meatus
4 Sinus:
C Types of extensions:
1 Head: rounded end. ex. head of the femur
2 Condyle: Knuckle­like. ex. occipital condyle
3 Facet: Flat surface. ex. rib facets 4 Spine: Sharp, pointy extension. ex. spines of the vertebrae
5 Trochanter: large bump: ex. greater trochanter of the femur
6 Crest: ridge­like edge. Ex. illiac crest.
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I Organization of the Skeleton
A The skeleton is divided into two portions:
1 Axial portion: Principal support of the body. Protects the vital organs. Rather ridgid portion and allows slight movement. Includes: skull, vertebrae, sternum. ribs, and the hyoid. Composed of 80 bones. Forms the main axis
2 Appendicular portion : Freely movable, Generally more subject to fractures than the axial skeleton. Includes: upper and lower extremities, pectoral and pelvic girdles.
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B The skull (22 bones)
1 Two portions: Cranium and facial.
2 Cranium: Houses and protects the brain
a 8 bones: 2 paired and 4 unpaired
1 Frontal
2 Parietal
3 Temporal
4 Occipital
5 Ethmoid
6 Sphenoid ­ Keystone b bones of the ear. 6 bones smallest in the body. hammer, anvil, stirrups
3 Facial Bones
a b
c
d
e
f Facial bones:
1 Mandible ­ 2 Maxilla(e) ­ 3 Zygomatic ­ 4 Nasal ­ 5 Lacrimal ­ 6 Inferior nasal Choncha(e)
7 Palatine ­ 8 Vomer
4 Hyoid Bone ­ 3
B Vertebral Column:
1 2
3
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5 Five regions a cervical
b thoracic
c lumbar
d sacral
e coccygeal
6 Curves of the Vertebral Column
a Normal Curves 1 4 curves that absorb shock and offset the force of gravity.
2 Cervical curve forms when the baby holds up the head
3 Lumbar curve forms when the baby begins to walk
b Abnormal curves
1 scoliosis
2 kyphosis
3 lordosis
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C Thorax
1 Sternum
a Xyphoid process, cartilage tip of the sternum: Referred to in CPR
2 Ribs: 12 pairs: True ribs, False ribs, floating ribs
II Appendicular Skeleton:
A Designed to help us move and manipulate our environment
B Upper limbs (arms) and lower limbs (legs)
C Bones all have duplicates: (bilateral symmetry)
D Girdles: bones that connect the limbs to the axial skeleton
E Upper limbs and girdle:
1 Pectoral or shoulder girdle: Attach the arms to the trunk: a Scapula(e): Shoulder blades
b Clavicles: Collarbones 2 Upper limbs:
a humerus
b radius and ulna
c carpals
d metacarpals
e phalanges
F Lower limbs and girdle
1 Pelvic girdle: Attaches legs to the trunk, supports body, attaches muscles that move the leg, protects organs urinary bladder, uterus
a composed of the os coxa(e)
1 illium
2 ischium
3 pubis
2 Lower limbs:
a Femur
b tibia and fibula
3 tarsals: 7 Calcanus = heel bone
4 metatarsals: 5
5 phalanges: 14
6 Arches of the foot: shock absorbers, Formed by the ligaments of the foot, Fallen arches or flat feet affects the way you walk, causes pain to the knee, hip, and back.
III Differences of Male and Female skeletons:
A Pelvic angle in male is narrower < 60 degrees than the female's angle
B Illium is higher and narrower in the male than female
C Bones of male are larger and heavier
D Coccyx movable in females
E Most differences are due to child bearing in women.
F Age can be determined by the degree of ossification. (growth plates)
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