Skeletal System
PARTS OF THE SKELETAL SYSTEM
1. Axial Skeleton
- bones that form the longitudinal axis of the body
2. Appendicular Skeleton
- bones of the limbs and girdles that are “appended”
(attached) to the axial skeleton
● joints - give the body flexibility and allow movement to
occur
● cartilages
● ligaments - fibrous cords that bind the bones together at
joints
● tendons - bind bone to muscle
FUNCTION OF THE BONES
● support of the body
● protection of soft organs
● movement due to attached skeletal muscles
● storage of minerals and fats
● blood cell formation (hematopoiesis)
★ The adult skeleton is composed of 206 bones.
CLASSIFICATION OF BONES
1. Compact Bone
- dense, looks smooth, and homogenous
- make up the bulk of the dia
- provides support and protection
2. Spongy Bone
- does not contain osteon
- composed of small needle-like pieces of bone and lots of
open space
L.G. ROM
,CLASSIFICATION OF BONES ACCORDING TO SHAPE
1. Long Bones
- typically longer than wide
- have a shaft with heads at both ends
- contain mostly compact bone
- e.g. all bones of the limbs (excluding patella), wrist bones,
ankle bones, femur, humerus
2. Short Bones
- generally cube-shaped
- contain mostly spongy bone
- e.g. carpals, tarsals, patella, sesamoid bones (special type
of short bone that forms within tendons)
3. Flat Bones
- thin, flattened, and usually curved
- have two thin layers of compact bone sandwiching a layer
of spongy bone between them
- e.g. skull, ribs, sternum
4. Irregular Bones
- do not fit one of the preceding categories
- e.g. vertebrae of the spinal column
L.G. ROM
, BONE GROWTH
1. Epiphyseal plates allow for the growth of long bone during
childhood
2. New cartilage is continuously formed
3. Older cartilage becomes ossified
4. Cartilage is broken down
5. Bone replaces cartilage
6. Bones are remodeled and lengthened until growth stops
7. Bones change shape somewhat
8. Bones grow in width
BONE FRACTURES
- a break in a bone
- are treated by reduction and immobilization or realignment of the
bone
TYPES OF BONE FRACTURES
1. Closed (simple) fracture
- break that does not penetrate the skin
2. Open (compound) fracture
- a broken bone penetrates through the skin
L.G. ROM
PARTS OF THE SKELETAL SYSTEM
1. Axial Skeleton
- bones that form the longitudinal axis of the body
2. Appendicular Skeleton
- bones of the limbs and girdles that are “appended”
(attached) to the axial skeleton
● joints - give the body flexibility and allow movement to
occur
● cartilages
● ligaments - fibrous cords that bind the bones together at
joints
● tendons - bind bone to muscle
FUNCTION OF THE BONES
● support of the body
● protection of soft organs
● movement due to attached skeletal muscles
● storage of minerals and fats
● blood cell formation (hematopoiesis)
★ The adult skeleton is composed of 206 bones.
CLASSIFICATION OF BONES
1. Compact Bone
- dense, looks smooth, and homogenous
- make up the bulk of the dia
- provides support and protection
2. Spongy Bone
- does not contain osteon
- composed of small needle-like pieces of bone and lots of
open space
L.G. ROM
,CLASSIFICATION OF BONES ACCORDING TO SHAPE
1. Long Bones
- typically longer than wide
- have a shaft with heads at both ends
- contain mostly compact bone
- e.g. all bones of the limbs (excluding patella), wrist bones,
ankle bones, femur, humerus
2. Short Bones
- generally cube-shaped
- contain mostly spongy bone
- e.g. carpals, tarsals, patella, sesamoid bones (special type
of short bone that forms within tendons)
3. Flat Bones
- thin, flattened, and usually curved
- have two thin layers of compact bone sandwiching a layer
of spongy bone between them
- e.g. skull, ribs, sternum
4. Irregular Bones
- do not fit one of the preceding categories
- e.g. vertebrae of the spinal column
L.G. ROM
, BONE GROWTH
1. Epiphyseal plates allow for the growth of long bone during
childhood
2. New cartilage is continuously formed
3. Older cartilage becomes ossified
4. Cartilage is broken down
5. Bone replaces cartilage
6. Bones are remodeled and lengthened until growth stops
7. Bones change shape somewhat
8. Bones grow in width
BONE FRACTURES
- a break in a bone
- are treated by reduction and immobilization or realignment of the
bone
TYPES OF BONE FRACTURES
1. Closed (simple) fracture
- break that does not penetrate the skin
2. Open (compound) fracture
- a broken bone penetrates through the skin
L.G. ROM
