6b. Pelvis HAL - Worksheet Flashcards
what are the 3 parts of the pelvic bone
ilium
ischium
pubis
what are the 2 landmarks of the ilium
iliac fossa and ASIS
what are the 2 landmarks for ischium
ischial tuberosity
ischial spine
what are the 2 bony landmarks of the pubis
pubic tubercle
pubis symphysis
what are the organs in the false pelvis
abdominal organs (eg caecum, appendix, sigmoid colon, small bowel)
what are the organs in the true pelvis
pelvis organs (eg bladder, uterus, rectum, prostate, vagina)
what divides the true and false pelvis
pelvic inlet - true is below the inlet and false is above
what does the sacrum consist of
5 fused vertebrae
what is the sacrums angle
superior portion is relatively horizontal and its distal portion is relatively vertical
in what view could you expect to see the sacral canal and its contents in its entirety
sagittal
can you assess S1-3 nerve roots simultaneously in a coronal plane
no due to angulation pf proximal portion as not in same vertical plane
what forms the SI joints
alae of the sacrum and the iliac bones
what kind of joint is the anterior SIJ
synovial joint
what kind of joint is the posterior SIJ
fibrous joint
the pubic symphysis joins the 2 pubic bones in what direction
anteriorly
if you see signs of trauma in one of these joints in the xray images what else do you want to check for and why
look for dislocation/fracture in other pelvic bones and joints as the pelvis is a ring structure and always fail in 2 places
from anterior to posterior what are the major organs in the male pelvis
bladder > rectum
from anterior to posterior what are the major organs in the female pelvis
bladder > uterus/vagina > rectum
what does the rectum usually contain that the other organs do not that make it easy to spot on cross sectional imaging
gas
which bones does the bladder always sit posterior to
pubic bones and symphysis
what is the rectouterine pouch/of douglas
forms the most inferior part of the abdominal cavity when patient is standing
why is the rectouterine pouch/of douglas clinically relevant
as it is the most dependent part of the abdomen when erect this is where things will gather such as fluid (blood/pus etc) or metastases/endometriosis cast offs etc
it is therefore an important area to check
what is anteversion of the uterus
uterus points to the front
in the female pelvis what lies on top of the bladder
uterus
what are the 2 other orientations of the uterus aside from anteversion
retroverted or midposed
the ovaries are linked to the uterus via what
uterine tubes
what is the relative position of the ovaries in the pelvis
on the lateral wall of the pelvis
what is the organ located inferior to the male bladder
prostate
is the prostate more or less dense than the bladder and why
more dense as the prostate is solid and not fluid filled while the bladder is fluid filled
what structures are associated with the posterior aspect of the bladder
3 things
ureters and the seminal vesicles and vas deferens
why would the ureter be of importance
assessing for kidney stone
above the pelvic inlet and nestled in the iliac bones are what organs
small and large bowels
what part of the large bowel is nestled close to the right iliac fossae
caecum/appendix
what part of the large bowel is nestled close to the left iliac fossae
sigmoid colon
the descending and ascending colon are between what 2 structures
between pelvic bones and ribs
the rectum begins at what vertebral level
S3 vertebral level
what is above the S3 vertebral level
sigmoid colon
what joint does the head of femur and acetabulum form
multiaxial synovial joint
do you expect to see the head and greater trochanter of the femur in the same axial slice
yes
superiorly we just see head but there is plenty of overlap more inferiorly
what 2 large muscles insert onto the greater trochanter
gluteus medius and minimus
what part of the pelvis do the gluteus med and min originate from
lateral and gluteal surface of ilium
what path do the psoas major and iliacus muscles take relative to the hip joint and what do they do at the insertion
pass anterior to hip joint and form common tendon on lesser trochanter
where do the psoas major and iliacus insert
lesser trochanter
how do you describe the appearance of the psoas maj muscle on a axial cross section
more circular
how do you describe the appearance of the iliacus muscle on a axial cross section
longer, thinner and flatter
what does the foramen look like on cross section
space between 2 bits of bone
filled with muscles and neurovascular stuff
what pelvic muscle passes through the GSF
piriformis
what neurovascular structure lies anterior to the piriformis
sacral plexus
the obturator internus fills what aspect of the which foramen
inner aspect of obturator foramen
where does the obturator internus pass out
LSF
what is the path of the obturator internus around the ischium
90 degree bend around the ischium
where does the obturator internus insert
femur
at what vertebral level does the abdominal aorta bifurcate
L4
what does the abdominal aorta bifurcate into
2 common iliac arteries
at what vertebral level does the IVC bifurcate
L5
what 2 vessels forms the IVC
common iliac veins
what is the relationship of the common iliac veins to the common iliac arteries
veins run medial to arteries but cross underneath - inferior
what is the issue of the relationship of the common iliac vein and arteries relationship
compression or obstruction
eg aneurysm or pregnancy
what do the common iliacs divide into
internal and external iliac vessesl
at the bifurcation of the common iliacs into the int and ext what structure will you find anterior to this point
ureter cross anterior to bifurcation of common iliac arteries
what skeletal landmark helps estimate the bifurcation of the common iliac vessels
anterior SIJ
what muscles do the external iliac vessels run anterior to
psoas major
the external iliac vessels are called what vessels after it passes under what structure
under inguinal ligament
femoral vessels
what is the femoral vessels joined by
femoral nerve
what is the order of structures from lateral to medial in the femoral triangle
nerve, artery, vein
what does the sacral plexus arise from in terms of nerve roots
L4-S4 of spinal cord
where do the sacral nerve roots contributing to the sacral plexus emerge from specifically
anterior sacral foramina
can you see all of the sacral nerve roots in one coronal plane
no as there is angulation of the sacrum posteriorly
the sacral plexus forms anteriorly to which muscle
piriformis
which space does the piriformis and the terminal branches of the sacral plexus exit the pelvis cavity
GSF
the sciatic nerve supplies what parts of the leg
posterior thigh and everything below the knee joint
what is the relation of the sciatic nerve to the hip joint
posterior relation
how can the sciatic nerve be compromised as it exits the pelvis
space occupying lesion in GSF can cause compression of nerve (eg inflammation of piriformis or tumor)
anatomical variation (eg nerve travels through piriformis and not under it)
pelvic fracture around GSF/SIJ
