Topic here is osteoporosis.
Allow the name to speak to you.
Increase in porosity within the bone, what
may then cause it?
Well, to begin with, take a look at the picture
on the left and we notice that, here, that
the bone and the trabeculae and such… oh,
everything is intact.
On the right, you’ll notice that this kind
of looks like a beehive.
What that basically means is that you have
your trabeculae that get very, very thinned
Think of this perhaps as being in the vertebrae
and if this type of thing... thinning is taking
place in the trabeculae with all these pressure
upon the vertebrae, you might then have [sound]
compression fracture because of weakening,
So, with osteoporosis, it’s skeletal disorder
characterized by compromised bone strength
predisposing to increased risk of fracture,
maybe perhaps compression factor of the vertebrae.
Bone remodelling, what does that mean to you?
Well, last time I talked about this was the
balance between osteoclasts and osteoblasts.
This is absolutely required so that you have
proper bone integrity.
The equilibrium between the formation of…
by osteoblasts and the resorption, meaning
to say, removal of the calcium from the bone
Well, that balance has been lost and when
such an imbalance takes place, why?
Well, maybe a female, as you know, as she
hits menopause at the age of 50, she has decreased
So, therefore, this decreased protection of
the bone may result in imbalance… osteoporosis.
Usually, on average, a peak bone mass is achieved
by 30; anything after that, well, it depends
on how the patient has been taking care of
himself or herself.
Around the fourth and fifth decade, later
on, so we’re talking about 40’s and 50’s,
the bone loss occurs automatically due to
age at approximately 0.5 percent per year.
Loss is accelerated in women due to loss of
estrogen and the reason for that is, if you
remember your pharmacology here, there’s
a particular drug called denosumab, I would
recommend that you go back and take a look
at that drug.
It is a drug that actually binds to RANK ligand
and what I mean by that is remember receptor
activated nuclear kappa Beta, RANK, responsible
for proper osteoclast activation or osteoclastogenesis.
What RANK ligand blockers do is not form excessive
Estrogen helps to block or control the amount
of osteoclastogenesis that’s taking place.
Therefore, osteoporosis is not a big deal
during reproductive age in a female.
Once the female hits menopause, estrogen drops.
Therefore, for the protection or the regulation
of osteoclastogenesis has also been lost.
May then result in loss of trabeculae, we
call this micr- oh, osteopenia and then may
result in microfractures and also compression
fractures, especially of the vertebrae.
And of course, whenever you’ve heard of
osteoporosis, you’re always worried about
this elderly female who may then slip and
fall maybe because she’s out shovelling
the snow in the winter and she slips on ice
and when she does, she has… experiences
a hip fracture.