Lecture 2 - Pelvis Flashcards
What’s the best mode of action for both traumatic and non-traumatic hip injuries?
a plain radiograph is the first thing
but if suspected with metastasis then further investigation should be done ie. skeletal survey
What are the common indications noticed on a radiograph that establish a hip injury?
- fractures
- major trauma surveys
- dislocation
- subluxation
- OA
- joint pain
- post surgery
- osteomyelitis
- metabolic bone disease
- pagets
- myeloma
- tumours
- TB
- ankylosing spondylitis
Name the different views of the plevis that can be done for a pelvic exmaination
AP pelvis
Lateral hips
- frog lateral
- turned obl (non-trauma)
- HBL for trauma
- modified axiolateral
Inlet and outlet projections
Posterior obl: Judet views
- RPO
- LPO
Flamingo view
AP PELVIS
sig:
- assess pelvis using lines, fracvtures, disatysis of symphysis, SI artiulcation, degeneration, bone lesions
tech:
- 24x30, 35x43 landscape
- filter may be used
- suspend on respiration
- in bucky
- exp: 66-70 kVp, 25-32 mAs, 120 or greater SID
pos:
- This projection can be bilateral or unilateral
.- supine with legs extended and slightly internally rotated (not if ?#) and arms folded across stomach or away from hips
rotation:
- ASIS equal in level to horizontal table top
- heels seperated by 20 cm
- internal rotation of 15-20 deg (toes touch). this allows max visualisation of femoral neck so its not necessary unless u want to see the necks (don’t do if trauma)
- median sagital plane in line with mid long axis of table
rotation check on image:
- OF size
- ala size
beam:
- between level of ASIS and symphysis
FOV:
- fem heads, fem neck, GT, pelvic girdle sacrum and occyx
Explain how radiation protection is adhered to with the pelvis projection
- do ot apply protection if its going to obstruct the viewing of necessary anatomy cuz this may lead to having to re-ray and so unnecessary exposure.
- accurate collimation
- immobilisation devices
- explanations to pts on procedure
- preggo
What’s the name of the gonad shielding and how is it varied between females and males?
Kings lynn
How can you palpate on someone who has a huuge ass muffin top?
GT: abduct unaffected lef and internally rotate lower leg while palpating
Large soft tissue fold of lower abdomen can superimpose the pelvic girdile and cause decreased desnities
- solution: ask pt to left soft tissue fold above/higher from pelvis (use wedge filter if need be but have to add 10 kV more)
Explain how to position pt for a frog lateral pelvis
sig:
- a paeds view usually
- SI joint, degeneration, bone lesions,
- provides lateral view of hip joint
tech:
- 24x30 landscape
- in bucky
- exp: 66-70 kVp 25-32mAs, >120
- suspend on respiration
pos:
- supine with legs spread out like frogs legs and arms folded across stomach or away from hips
rotation: - ASIS equal in level to horizontal table top
- heels seperated by 20 cm
- median sagital plane in line with mid long axis of table
rotation check on image:
- OF size
- ala size
TURNED OBLIQUE PELVIS
DO NOT DO FOR TRAUMA
all this is a unilateral frog lateral, so orient the pt so that the affceted side’sleg is frogged out and is towards the surface.
flex hip and knee of the affected side, then abduct the thigh laterally aprox 45deg
HBL LATERAL HIP
ESSENTIALLY AXIOLATERAL PROJECTION
sig:
- to see hip joint in a lateral aspect
- trauma pts, frac, dislocations
tech:
- 24x30 landscape
- filter can be used
- grid placed with cassette
- exp: 80 kVp 40 mAs
pos:
- unaffcted leg flexed 90 deg and out of FOV (rest on a chair)
- ensure no pelvic rotation
- internally rotate 15-20 deg affected leg (NOT FOR TRAUMA)
- IR placed in crease above iliac crest and make it parallel to fem neck slope and perp to beam
BEAM:
- centre to inguinal crease (so the middle of fem neck)
FOV:
- hip joint and prox femur shown
MODIFIED AXIOLATERAL HIP
an axiolateral hip is done when unaffected leg can’t be flexed and moved out of FOV
PELVIC INLET VIEW
position the pt like an AP pelvis but angle the beam caudal 30-40 deg.
Why is a pelvic inlet view done?
- shows amount of vertical displacement of frac
- medial/lat rotation of ant pelvis
- to see pelvic rim well
PELVIC OUTLET VIEW
this is one of the only additional views that is suited for a trauma pt. angle beam cephald 30-40 deg
whats the purpose of doing a pelvic outlet view?
establish orientation od pubic rami displacement/fracture
JUDET’S VIEW
sig:
- to see injuries to acetabulum (post or ant column injury)
- can only be done after an orthopaedic evaluation that confirms pelvic stability
- ITS A POSTERIOR OBLIQUE OF HIP JOINT
- both posterior and anterior rim of the acetebelum is done
ANALYSE RIGHT ACETEBLUM:
- do LPO = see post brim of right ace (ie. raised side, internal oblique)
- do RPO = see ant brim of right ace (ie. depressed side, external oblique)
ANALYSE LEFT ACE:
- LPO = to see ant brim of left ace (ie. depressed side, ext obl)
- RPO = to see post brim of left ace (ie. raised side, int obl)
THEREFORE,
RAISED (int obl)= POST BRIM (CR: 5cm distal to ASIS)
DEPRESSED (ext obl) = ANT BRIM (CR: 5cm medial to ASIS)
What’s shown in a INTERNALLY OBLIQUED ACETBEULM? IE. RAISED SIDE
the posterior brim of acetbulm superimposed by fem head…but you can still see it
iliac wing foreshortened
ant iliopubic column
OF open
fem neck well demosntrated
What’s shown in a externally obliqued acetebelum? ie. depressed side
ant brim of ace partially superimposed by head
iliac wing elongated
fem head
pos ilioischial column
OF closed
dem neck squashed
FLAMINGO VIEW
sig:
- weight bearing view of symphysis to distinguish extent of stability, subluxation and/or osteitis pubis
best done PA
POS:
- weight bear on one leg each time
beam:
- pubic symphysis
What’re the lines used to distinguish pelvic injuries?
shentons
iliopectineal
ilioischial
teardrop sign
acetebular roof
ant wall (rim) of ace
post rim of ace
normal diatnce between symphysis joint
<2.5cm in adult
What’s a dynamic screw?
prosthesis for wear and tear injuris of hip
provides strong abd stable internal fixation for a variety of neck of femr and trochanteric frac
provides rapid pt mobilisation (can leave hospital like that day lol)
What’s THR?
total hip replacement
- possibly due to OA
head of femur replaced b metal ball or stem
Explain what’s OA of hip
DJD: cartilage destruction and bony erosion
joint space narrowing
loss of smooth articulatory surface
SOLUTION = THR
