Test 3: Imaging Flashcards
what are the routine radiographs of the hip
lateral frog leg
AP
what can you visualize with a hip AP radiograph
hip joint and proximal femur
looking at iliofemoral line, shenton’s hip line, and femoral neck angle
what are the iliofemoral line and shenton’s hip line
iliofemoral = smooth curve alone outer ilium that extends into neck
shenton’s = smooth curve around obturator foramen
important obervations when viewing the hip xray (ABCDS)
well preserved joint space
smooth margins of acetabulum/femoral head
obvious ball and socket
cortex margins on shaft
cancellous markings on head and neck
what is the purpose of the lateral frog view
visualizes head, neck, and proximal femur
lesser trochanter is more anterior
routine radiographs of the knee
AP
lateral
PA axial “tunnel” view
tangential
what can you see with a knee AP view
distal femur
proximal tibia (and respective joint)
fibular head
important things to obeserve with AP knee
patella superimposed and not typically visible unless baja
well defined/equal joint spaces
tibia/femur alignment
distinct cortical margins and cancellous markings
advantage of the knee lateral view
visualize profile of PF joint
can determine alta/baja positioning of patella
how similar should the length of the patella and the patellar tendon be?
within 20% variance
what can you view with the knee PA axial tunnel view
intercondylar fossa and eminence
posterior femur and tibia
tibial plateaus
used to detect loose bodies, osteochondral defexts, or narrowing of joint space
performed in standing for ARJC
tunnel should be round and open
what can you see with the knee tangential view
PF joint space and surfaces
can see sulcus angle; obs depth; if shallow may be more prone to dislocation
can see congruence angle; helps determine patellar position within sulcus (>16 deg associated with hyper)
ottawa knee rules
over 55
fibular head tenderness
isolated patellar tenderness
inability to flex knee to 90
inability to walk 4 steps after injury
routine ankle radiographs
AP
AP oblique
lateral
what can you see with the ankle AP view
distal tib/fib and talar dome
lateral malleolus should me more distal than medial
can see upper and medial talus; medial or lateral shift is abnormal
cam see distal tib/fib joint space
what can you see with the ankle AP oblique view
mortise is visible with 15-20 deg hip IR
can see entire talocrural joint space
mortise is typically 3-4 mm or < 1/2 cm all the way around
> 6mm measure used for syndesmotic injury
what can you see with ankle lateral view
tibiotalar and subtalar
talonavicular and calcaneocuboid joints
bony members
what is the ankle anterior drawer stress view used for
xray while performing ligament test
measure from tibia to posterior talus
normal = 5mm or 1/2 cm
abnormal = > 10 mm or 1 cm
5-10 mm of separation requires comparison between sides
what is the ankle EV/IV stress view used for
measure angle between the bottom of the tibia and the talar dome
abnormal = mortise widens, >15 deg for IV or >10 deg for EV
also abnormal if >5 deg difference between sides
routine radiographs for foot
AP
lateral
oblique
what can you see with foot AP view
mid and fore foot
can note individual bones
look at 1st intermetatarsal angle; intersection of lines bisecting 1st and 2nd MT shafts (normal is < 5-10 deg)
what can you see with the lateral view of the foot
subtalar, talonavicular, and calcaneocuboid joints and members
different from ankle because less tibiofibular imaged
what can you see with the foot oblique view
foot and leg medially rotated
visualizes forefoot primarily but also all tarsals except cuneiform and a portion of the talus
important observations with foot oblique view
MTs image with sharp clearly defined cortical borders
sesamoids
2nd-4th distal phalanges DIFFICULT TO SEE
joint spaces and midtarsal joints
