Bone Basics
how many bones are in the human body?
206
how many types of bones are there?
5
Bones ossify completely between what ages?
18-25
what is the name for cartilage cells?
chondrocytes
When a fracture first takes place, what happens first?
the formation of a hematoma
what are the two subdivisions of the skeleton?
axial and appendicular
cancellous bone with a thin layer of compact bone
compact bone makes up what region of the long bone?
diaphysis
What type of cartilage makes up the template for bone during endochondral ossification?
hyaline cartilage
Which two cells create a callus near the fracture site?
chondrocytes and osteoblasts
bone matrix is called _________.
osteiod
how many types of bones have a medullary cavity
1-long
if your body experiences significant blood loss, ____________ marrow transforms into __________ marrow.
yellow; red
What develops around the cartilage model?
perichondrium
When ____________ produce osteoids and become osteocytes, _________ are no longer needed and die.
osteoblasts; chondrocytes
bones produce which hormone that helps with other systemic processes?
osteocalcin
where are sesamoid bones usually found?
next to joint surfaces and tendons
A tiny hole in the bone that blood vessels thread through
nutrient foramen
How do the medullary cavities develop?
medullary cavities are developed primarily by the osteoclasts breaking down newly formed bone in the center of the bone.
a ___________ fracture is when the broken ends of the bones are jammed together by the force of the injury.
impacted
the skull protects the ___________, the rib cage protects the ____________, and the vertebrae protects the _____________.
brain, heart and lungs, and spinal cord.
give an example for each type of bone
femur- long, short- cuneiforms, flat- sternum, sesamoid- patella, irregular- vertebrae
articular-ends
hyaline- growth plates
true or false. All bones undergo endochondral ossification.
false.
A contact injury took place where someone's tibia was sticking out of their leg. It was obvious that the bone has been broken in at least 4 places. Additionally, it appears part of the bone is floating. What are 4 fracture descriptors that could explain this injury best?
displaced, open, segmental, comminuted