when discussing the skeletal system probably the most clinically relevant area is fractures
secondly very closely associated is osteoporosis osteoporosis is one of the major causes for
fractures particularly in older individuals so really what is it so let's look at this
illustration here and we're focused in on this is a femur and we're focused in on the spongy
bone region as you can see in typical bone or normal bone you will still have spaces that's
normal in terms of spongy bone in osteoporotic bone that osteoclast activity so remember osteoclasts
are resorbing bone that's going to stay fairly normal in osteoporotic individuals
what isn't normal is osteoblast activity so you don't have the replacement of new bone keeping
up with the resorption of breaking down of bone so what you're going to be left with are these
spongy bone regions where you have significantly larger areas in holes within the bone so anytime
that you don't have bone where you need to be structurally that's going to play a big role and
can lead to fractures and that's really the number one symptom of osteoporosis now typically they're
not the more extreme version so you're not going to have these compound fractures generally you'll
have what's referred to as stress fractures more commonly but with more stress fractures that can
lead to those more severe types so either this comminuted fractures or the compound fractures
that we've discussed in previous sections with fracture of course you're going to have bone
pain so you're gonna have those sensory neurons sending signals back to the central nervous system
saying something's going wrong in this area even if it's not visible externally you can generally
feel pain in that region one of the other more common symptoms is shrinkage of vertebra and
with that you get height loss and you can get a fairly characteristic presentation of kyphosis
and colloquially we refer to this as hunchback so with time you can get this kind of very distinct
hunching of the back and what's happening and what's actually allowing this to happen is
you're gonna have multitude of stress fractures in the body of the vertebra and the body of
vertebrae are is composed of almost exclusively spongy bone so to have these stress fractures
that will eventually lead to the collapse of the body of the vertebra and if you have this occur
multiple vertebrae that can lead to height loss and individuals with osteoporosis now who does
this occur to most individuals if they live long enough we're going to have some level of
osteoporosis generally like I was just discussing it'll be shown in terms of the vertebrae you can
have it in other areas of the body as well and this typically happens in elderly individuals and
even middle-aged individuals now there's a higher incidence and women not to say that males don't
also have osteoporosis generally it's more likely to to show up in terms of women so in terms of
osteoporotic clinical practice women are going to be the patients more often and this can occur for
numerous reasons the two main reasons reasons are women just do not have as large of a body
build as males typically so sexually dimorphic dimorphic characteristics between women and men
women had the smaller body build anytime that you had that smaller body build that has implications
in terms of how much spongy bone there is in that area secondly estrogen production slows down in
women as well whereas testosterone in males typically can you have normal secretion even
later on in life so that can play a role in terms of osteoporosis other risk factors family history
like many other disorders so if your mother or your grandmother had osteoporosis you're typically
more likely to have it ancestry can also play a role so individuals of European or Asian ancestry
typically have a higher incidence of osteoporosis as we discuss previously small body build can
play a role an inactive lifestyle if you're not doing those weight-bearing exercises that are
contracting those muscles and affecting the bone that is attached to that can really play a role
in terms of not changing the bone not having those osteoblasts secreting at a normal level