Ankle Flashcards
what is the SID for ankle views
100-110cm
what is the kV for ankle views
60-70kV
what is the mAs for ankle views
3-4mAs
do you use grids for the ankle views
no
what is the AP ankle patient positioning
in terms of the leg and malleoluses
sit on table, affected leg extended and ankle in contact with IR
lateral malleolus posterior to the medial mortise joint
what joint needs to be open for an AP ankle
open mortise joint
what is the CP for an AP ankle view
perpendicular to midway between the intermalleolar line
what is the CP for an AP mortise ankle
perpendicular to center of the mid intermalleolar line
what is the patient positioning for an AP mortise ankle
in terms of the foot rotation and malleoluses
internally rotated foot so intermalleolar line is parallel to the IR
vertical line runs along 4/5th toe
lateral malleolus should be the same height as the medial one
what is the CP for a lateral ankle
perpendicular to the center of the medial malleolus
what 2 joints need to be open for an AP mortise ankle
medial and lateral mortise joints
what is the patient positioning for the lateral ankle view
in terms of the malleoluses, spong pad use, foot flexion
lateral malleolus of ankle in contact with IR
sponge under knee (and foot if needed)
dorsiflex foot
malleoli superimposed
what is the CP of an oblique ankle
perpendicular to midway between the malleoli
what is the patient positioning for an oblique ankle
in terms of leg and foot rotation
affected leg extended so ankle is in contact with the IR
turn foot 45* medially
what are the 3 ankle stress views
which needs assistance by an ED
gravity standard stress views
eversion and inversion stress views = need assistance
what are the gravity ankle stress views used for
medial ligamentous injury that isnt apparent on initial x-rays
weber B classifications
what is the patient positioning for gravity standard stress views
in terms of leg, detector and foot rotation
patient lies on side with injured leg over edge of bed
detector placed behind heel and foot is internally rotated to mortise
what is the image critique for an AP ankle position
in terms of the 3 joint spaces and whether they should be open/closed
medial mortise open
lateral mortise closed
clear joint space between the tibia and talus
what is the image critique for an AP ankle position
in terms of superimposition of structures
some superimposition of the distal fibula and talus
what is the image critique for an lateral ankle position
in terms of superimposition of structures
lateral malleolus superimposed over the posterior half of the tibia
talar domes superimposed
in terms of the image critique for an lateral ankle position
what will we see if the ankle is over or under rotated
under rotated = shaft of fibula superimposed on tibia or anterior to it
over rotated = fibular projected too far posterior to the tibia
what is the image critique for an mortise ankle position
in terms of the joint spaces, superimposition and malleoli
entire mortise joint open
superior tarsal joint free of superimposition
malleoli in profile
what is the image critique for an oblique ankle position
in terms of joint spaces
distal tibiofibular joint space open
what is the image critique for an lateral ankle area of interest
7 things
entire talus and calcaneus
distal 1/3 tibia and fibula
5th MT tuberosity
navicular and cubiod
