Pelvis Flashcards
Normal angulation of a femur?
15-20 deg
Best way to visualise the NOF
Internal rotation of the foot, leads to anteversion
Radiation protection for Pelvis
Gonadal
for females sheild 1.5cm cm from pube symph , can always place sheilding diagnonally.
If a patient cannot roll for a lateral hip what projection should be used?
Danelius-Miller “shoot through Lateral’
IF a patient cant roll or lift theyre good leg, what projection should be used for a lateral pelvis?
Clements-Nakayama.
What other image should be taken if there is a suspected # of pelvis?
CxR
What projection is best used for a pubic symphysis #?
Inlet/ Outlet.
What are the standard projections for pelvis?
AP hip/ pelvis
Lateral
Whats important to remember during hip projections
Prosthesis (wider collimation)
IF the foot is in internal rotation where will the greater trochanter be projected?
Laterally.
Describe patient positioning for lateral hip
Unafflicted leg is raised out of way, typically elevated by a sponge
affliected leg is abducted and turned into ext roration (like a single frog leg).
Positioing of trochanters on a lateral hip?
close to SI
Angulation and anatomy shown for Inlet pelvis view
40 caudad
Pube symph projected inferiorly, pelvic cavity shown
Ischium is anterior to pelvis
Angulation and anatomy shown for outlet view
35 cephalad
Pube symph projected superiorly
Pubic symph over mid sacrum. Obturator shown.
another name for frog-legged pelvis
Bilateral Lateral pelvis/ hip
What is Frog-legged pelvis view typically used for?
SKFE
Calve’s
Why is clements-nakayama done without a grid?
Air gap and double agnulation increases grid cut off.
Which is the other trauma lateral that is typically never used?
Sanderson
Bucket handle #
High energy sagital force -> compression
Illiac crest moves superiorly nad medially as it ‘pivots’ off the spine.
to obturator foramen and unilateraly SI disruption.
Look a tthe pelvis bilaterally to see a unilateral rotation.
Common MOI for pevlis injuries
falls.
what does 6/7 mean on a patients clinical history
6 out of 7 days.
Duverney fracture
Saggital Force to illac crest
on illac crest.
Less complications diue to less Mm. on illiac crest.
Another name for pubic symphysis dislocation
DIASTASIS
Reasons to not do SI projection prone (PA)
Dose
increased FFD
more painful for patient.
Common MOI for SI joint dislocation
Child birth
Coronal F to illac crest
Bike riding
any external roational force to illiac crest.
Straddle #
Coronal F applied directly to pubic symphysis through saddle or Motorbike.
2 # to superior and inferior obturator foramen. BILATERAL.
meaning 4# quadpartite.
further imaging needed for ballder and viscera.
Vertical sheer / malgaigne #
Unilateral shearing F -> compression. e.g. falling off balcony and landing on one leg.
Vertical # through Hemi-pelvis. 3 or more # +/- disconuinitiesto obturator foramen and SI joint.
HEMIPELVIS IS PUSHED SUPERIORLY.
Most common NOF #
Intertrochantric #
NOF survival rate
25%
If a leg is naturally internally rotated what could it be an indication of?
Hip dislocation
IF a leg is externally rotate what can it be an indication of?
NOF#
typically foreshortened and NOF # due to snapped Psoas tendon.
Sub capital NOF #
below articular surface of #
CAN HAVE MINIMAL DISPLACEMENT
High chance of disrupting blood supply.
Intertrochantric #
Older patients and falling #
follows the greater and lesser trochanter
Treated with gamma nail
typically use Denilius-Miller.
Whcih NOF # is a common Insufficency #
Intertrochanteric.
What direction do most hip dislocations move in?
Posteriorly 90%
Can a hip dislocation foreshorten the leg?
yes.
What projection is needed to assess a hip dislocation for allignment?
Lateral
What patient presentation typically causes a hip dislocation?
Prosthesis.
What does SCFE stand for?
Slipped capital femoral epiphysis.
Slipped Capital Femoral Epiphysis.
Dislocation of growth plate (DONT MISTAKE FOR #)
Common with adoloscent males with hypersthenic
Cant occur once growth plate has fused.
Need to be aware of femoral vasculature and growth plate.
secure dislocation without prematural growth plate fusion.
try to avoid CT due to dose.
Legg-Calve-Perthe’s dissease
MOI : UKNOWN
Flattened or teardrop fem head.
Avascularisation of femoral articular surface .
crumbled femoral head + shallow acetabulum.
Predisposition to: Dislocation, Poor Gait, Arthritic change.
