Where is the glute muscle
Gluteal muscles (anatomy)
alright hello everybody today we're
going this way around because I did my
ultra marathon on the weekend and my
legs still hurt and this week's topic is
partly because of that but largely
because in a recent exam students seem
to get their understanding of the
gluteal muscles a little bit
ass-backwards if you'll excuse the pun
so we're going down here to the gluteal
region I've looked at the muscles that
the large muscles of the hip and the
small muscles of the hip in the past
today I'm doing three muscles gluteus
maximus gluteus medius and gluteus
minimus we're gonna talk about what they
attach to what happens when they
contract what their jobs are what their
innovation is and then the thing I
really want to get clear is what happens
if they don't work properly I think it's
pretty straightforward I'm just gonna
try and keep it super clear alright I'm
not entirely sure this was the best idea
it's my leg still so now I got I didn't
think this through did I anyway gluteus
maximus so the shape of the buttocks is
largely formed by gluteus maximus it's a
really big muscle which tells you is
therefore power powerful movements and
the reason is so powerful is because
it's it aids in lifting our entire body
weight this is the gluteal cleft between
the two gluteal bits as the vertical bit
and the gluteal fold is the horizontal
bit beneath the gluteal bits the
buttocks right what could see the
gluteus maximus then well gluteus
maximus it's coming from so this is the
pelvis this is the ilium nice this is
the posterior bit of what we're looking
at here this is the ilium right ilium
ischium
and then pubis around here so gluteus
maximus then is clearly coming from the
ilium part of the pelvis now if you've
got a really good ilium like I'm really
not not you but if you've got a skeleton
with a really good in
you can see anterior posterior inferior
gluteal lines little lines on here right
will show you where the muscles attach
some of these is a good skeleton is a
very expensive skeleton I'm not seeing
those lines and mouth looking a real
alien to see them anywho it also
attaches to the sacrum and your base the
coccyx right so it's coming it's
attached with all of these bones down
here and then is running across the hip
joint to the femur now if this is the
diathesis here this big lump is the
greater trochanter this is the little -
cancer there just then here we haven't
really got one there's a gluteal
tuberosity a little little knobbly bit
some of the fibers of gluteus maximus
insert into the femur this is the
posterior femur that the gluteal
tuberosity but most of the fibers don't
most of the fibers inserts into the
flash' what I mean is that is that the
the lower limb is covered in a layer of
fairly tough deep fascia holds
everything in place right keeps the
muscles in groups and that fascia is
thickened laterally here's the hip the
knees down then there this is the Meo
tibial tract or the iliotibial band so
it goes from the ilium all the way down
to the tibia down here
now this elio tibial try to really a
tibial band something else that one is
care about because if it gets too tight
the tensor fasciae latae pulls on
another muscle causes a bit any pain see
your phone roll right anyway the reason
it's here is to give some stability to
the lower limb when you're standing
walking in that sort of thing but all it
is is a thickening of the fashio
of the fasciae latae of the lower limb
of the of the thigh here so we see as
this band largely when you're deciding
is like thinner here and thicker it's
you kind of cut it out if you look
pretty make you stand out now my point
is that most of the fibers of gluteus
maximus insert into the iliotibial tract
into the deep fascia of the leg salutis
maximus crosses the hip joint
is very good at helping you stand up and
when I had to do them was to raise
almost all of my body weight up so
extension of the hip joint right so this
is flexion of the thigh at the hip joint
so this is that is extension of the
thigh at the hip joint or hamstrings are
good at that
gluteus maximus is is also good so when
you walk you're mostly using your
hamstrings not really your glutes the
gluteus maximus is like is like your
turbo boost it's like your extra jet it
gives you that extra power when you need
to extend your hip joint and it's
particularly powerful when you're
extending from a flexed position or
partially flexed position most notably
when we're getting out of a chair right
so when you sat in the chair your hip
joint is flexed you at 90 degrees right
so when you stand up shouldn't need to
use your arms oh then you're engaging
gluteus maximus and going from going
from a flexed hip to an extended hip
course when you sit down when you're
lowering yourself gluteus maximus is
also lowering you slowly against gravity
so that's gluteus maximus great when
you're getting our chairs running
sprinting jumping climbing going up
stairs that's all think that's what
gluteus maximus is for all right now
gluteus maximus is innervated by the
inferior gluteal nerve there are two
gluteal nerves as an inferior gluteal
nerve and the superior gluteal nerve
remember our backers like Heraclitus
maximus it's big but it's it's the
inferior most muscle of the gluteal
muscles take gluteus maximus off here we
can see at least gluteus medius this
might be gluteus minimus here are those
not labeled as such but gluteus medius
and minimus then see how they're higher
up so they were innovated by the
superior gluteal nerve inferior gluteal
nerve
right gluteus medius and minimus are
also running from the ilium but they're
both running to the greater trochanter
of the femur the greater trochanter of
the femur is this lovely big bony bit
here roast they're running across from
the ilium so the greater trochanter of
the femur the media sees is more
superficial and minimus is deep now what
this means is there is that again
they're not actually powerful extensors
they're powerful abductors of the hip
joint so if they run across from there
because the greater trochanter is look
this is lateral is sticking out to the
side here because they pull out there
they're actually quite good at pulling
on the great circuit trochanter and
pulling the femur out away from the
midline so gluteus medius and minimus
are powerful abductors of the thigh at
the hip joint so you pull on the greater
trochanter the femur gets pulled away
from the midline so this is abduction of
the hip
so for gluteus medius and minimus bunk
right that's a production of the hip so
abduction of the thigh at the hip and if
you think about it because of that if
you if you think about this choice if
the if the hip join then is partially
flexed because we're running across this
joints the greater trochanter if you put
on the greater trochanter you'll also
get some medial rotation of the hip
joints they're quite good at medial
rotation of the femur at the hip gluteus
maximus does the opposite it can help in
lateral rotation again but it's you know
it's when you flex like this way so
gluteus booty's Maximus or powerful
extensors of the hip gluteus medius and
minimus powerful abductors of the hip
why is all this important well it's
because we're bipedal animals and we
walk and every time said this before but
every time we take a step we take one
foot off the ground so that means that
every time you take one foot off the
gray
and hey look I can take my foot off the
ground and put it back on again and the
pelvis stays level
this is gluteus medius and minimus on
this side because I'm taking this four
off the ground they're contracting and
keeping my pelvis level if gluteus
medius and minimus don't contract my
pelvis drops and if I try and bring my
foot back down
oh it's Gus on the floor that's the
concept that students seem to be
struggling with so if the superior
gluteal nerve is damaged or maybe the l5
root which is part of the superior
gluteal nerve but if you if the l5 nerve
root was damaged you see foot drop and
other things as well right
so just consider damage to the superior
gluteal nerve it could happen through
trauma through like hip replacement
surgery hip fracture or like an
intramuscular arrangement and
intramuscular injection injection is the
body would do the wrong place right that
was a superior gluteal nerve if you want
to test to see if gluteus medius and
minimus are working you just ask move
I've run a hundred K so I'm wobbly you
ask the person to stand on one leg and
you look for the stability and you look
for the pelvis staying level if gluteus
medius and minimus a week they will
struggle to keep the pelvis level right
what this means is for you if you have a
weakness in gluteus medius and minimus
it means that that as you take that foot
off the ground the pelvis drops so the
foot doesn't swing through so you have
to compensate and what we typically see
is Trendelenburg sign the Trendelenburg
sign is when you ask somebody to stand
on one leg the pelvis drops to the other
side and that's a sign the gluteus
medius and minimus are weak for some
reason so you see the person then
leaning out see if you lean over that
way if you lean your body way over the
side with the pathology over the weak
side your body way you can lift the hip
on our side and you can swing your foot
through you might see also see a
swinging gait and a swinging gait then
is the pelvis drops and you swing the
foot out to the outside right see pelvis
drops swing the foot out around or you
might see a high stepping gate so the
pelvis drops so you bring the knee
forward more to compensate to get the
foot through so high step is gate
swinging gate Trendelenburg sign those
are all the signs that the pelvis isn't
staying level when you take one foot off
the ground
if the pelvis isn't staying level then
that's gluteus medius and gluteus
minimus and maybe the superior gluteal
nerve or something like that all right
so Trendelenburg sign is hip dropping to
the opposite side to the weakness and
then even a waddling gait gluteal gait
high step each gate swinging gate all
those sorts of things that's it that's
all I wanted to do because it's Maximus
extensor of the hip powerful when the
thigh is flexed to the hip gluteus
medius and minimus abductors of the hip
their job is to keep the pelvis level
when you take the leg on the opposite
side to the muscle off the floor so if
the weakness is on one side it's the
foot on the other side that's gonna drag
or something strange is gonna happen to
it those are the key points right
another cup of tea cup of teas a
recovery drink of choice right I'll be
fine this time next week see you next
week
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