THE SKELETAL SYSTEM

FUNCTIONS OF BONES

• SUPPORT: THEY PROVIDE A FRAMEWORK• PROTECTION: THE SKULL PROTECTS THE BRAIN & THE

VERTEBRAE PROTECT THE SPINAL CORD, ETC.• MOVEMENT: BONES ACT AS LEVERS TO MOVE THE

BODY• MINERAL STORAGE: BONES ACT AS A RESERVOIR FOR

Ca AND P• BLOOD CELL FORMATION: MOST BLOOD CELL

FORMATION OCCURS WITHIN THE MARROW OF BONES.

CLASSIFICATION OF BONES

• ARE LONGER THAN WIDE

• E.g.. BONES OF THE LIMBS, EXCEPT PATELLA, BONES OF WRIST & ANKLE

LONG BONES

SHORT BONES

• ARE ROUGHLY CUBELIKE..

• E.g.. BONES OF WRIST & ANKLE

• ARE THIN• FLATTENED

• A BIT CURVED• E.g.. MOST SKULL BONES

FLAT BONES

• FIT NONE OF THE OTHER CLASSES.

• E.g.. VERTEBRAE & HIP BONES

IRREGULAR BONE

TERMS• EPIPHYSES- SWOLLEN ENDS OF THE BONE

• DIAPHYSIS- SHAFT OF THE BONE

• EPIPHYSEAL PLATE- AREA OF A BONE WHERE GROWTH OCCURS IN CHILDHOOD.

• MEDULLARY CAVITY- THE CENTER OF A BONE

• IN ADULTS, THE MEDULLARY CAVITY IS FILLED WITH YELLOW MARROW.

• YELLOW CAN CONVERT TO RED, WHICH MAKES NEW BLOOD CELLS, IF A PERSON BECOMES VERY ANEMIC.

SLIDE OF BONE TISSUE

OSTEOGENESIS

• IS THE PROCESS OF BONE FORMATION

• AT 6 WEEKS, THE SKELETON IS FIBROUS MEMBRANE AND CARTILAGE WHICH ARE FLEXIBLE. (this is important for the fetus to get through the birth canal)

fetus just prior to birth

HORMONAL IMBALANCES

GH (growth hormone) is a hormone that is important in bone

growth.

DWARFISM: TOO LITTLE GH

GIANTISM: TOO MUCH GH

DWARFISM

GIANTISM

BONE BREAKAGE

IS THE MOST COMMON BONE DISORDER

***PLEASE NOTE

(some of these pictures of fractures are graphic, so please do not view if you are uncomfortable; pictures follow the information about each

type of break)

COMMON TYPES OF FRACTURES

• SIMPLE• COMPOUND

• COMMINUTED• COMPRESSION

• DEPRESSED• IMPACTED

• SPIRAL• GREENSTICK

SIMPLE FRACTURE

• ALSO CALLED A CLOSED FRACTURE

• BONES BREAK CLEANLY BUT DO NOT PENETRATE THE SKIN

COMPOUND FRACTURE

• MORE SERIOUS THAN SIMPLE• BROKEN ENDS OF BONE PENETRATE THE

SKIN• BONE INFECTIONS KNOWN AS

OSTEOMYELITIS ARE POSSIBLE• ANTIBIOTICS ARE REQUIRED

click to view photograph of

compound fracture.

click to view photograph of compound fracture

COMMINUTED FRACTURE

• BONE FRAGMENTS INTO MANY PIECES• COMMON IN THE AGED WHERE BONES

ARE BRITTLE

COMMINUTED FRACTURE

COMPRESSION FRACTURE

• BONE IS CRUSHED

• COMMON IN POROUS BONES (THOSE WITH OSTEOPOROSIS)

DEPRESSION FRACTURE

• BONE IS PRESSED INWARD

• TYPICAL OF SKULL FRACTURE

IMPACTED FRACTURE

• BROKEN BONE ENDS ARE FORCED INTO ONE ANOTHER

• COMMON WHEN TRYING TO BREAK A FALL WITH ONE’S ARM

Mrs. Adams – a 67 year old female who fell on the ice

This is an impacted, comminuted fracture of the distal end of the radius.

SPIRAL FRACTURE

• RAGGED BREAK THAT OCCURS WITH A TWIST TO THE BONE

• COMMON SPORTS FRACTURE

GREENSTICK FRACTURE

• BONE BREAKS INCOMPLETELY

• COMMON IN CHILDREN WITH FLEXIBLE BONES

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