MSK Mod 1 Flashcards
describe short bones
examples of short bones
tend to be equal in both dimension - cuboidal shape
carpals of wrist, tarsals of foot
function of flat bones and example
protective
skull
examples of irregular bones
vertebrae, facial bones
characteristics of long bone
- diaphysis
- metaphysis
- epiphysis
- epiphyseal plate
what is the diaphysis
primary ossification center
body of bone
what is the metaphysis
flattened portion of the diaphysis
what is the epiphysis
secondary ossification center (develop after birth)
what is the epiphyseal plate
cartilagenous growth plate bw diaphysis and epiphysis
two types of bone tissue
compact (cortical) and spongey (cancellous, trabecular)
cortical bone
how much of skeleton does it make up
turn over rate
forms 80% of human skeleton
slow turn over rate
dense, tightly pack osteons with Haversian canal system
what is the haversian system
- haversian canal - each canal contains blood vessel and nerve that communicate with periosteum
- concentric layers of bone surround the canal - lamelle
- osteocytes found within concentric layers
what is the canal system connecting to periosteum
Volkman’s canal - horizontal canal system
cancellous bone
20% of skeletal mass
less dense but large surface area
higher turnover rate
undergoes remodeling according to line of stress
what is Wolff’s law
increased mechanical stress will increase bone density
applies to cancellous bone
what is periosteum
thin, double layered, tough fibrous membrane that surrounds the bone
surrounds all of bone except at ligament or tendon insertion sites
-difficult to separate the periosteum from the bone
2 layers of periosteum
- outer
2. inner
what does the outer layer of periosteum contain
contains capillaries and nerves
what does inner layer of periosteum contain
-Sharpey’s fibers anchor periosteum (as well as tendons and ligaments) to the cortical bone
if there is active bone formation then the inner layer of periosteum contains
osteoblasts
if there is inactive bone formation then the inner layer contains
fibroblasts that can become osteoblasts if new growth is needed
what is the bone marrow
confined to cavities bw osseous component of bone
aka myeloid tissue
bone marrow consists of
blood vessels nerves mononuclear phagocytes stem cells blood cells in various stages of differentiation fatty tissue
function of bone marrow
formation of blood cells
two types of marrow in adults
- red
2. yellow