Ankle - Mortise

Radiographic Positioning

Adult

Other related pages of interest Applied Radiography Radiographic Anatomy Radiographic Protocols

Name of projection	Ankle - Mortise
Area Covered	Distal third of the tibia and fibula, proximal half of the metatarsals, lateral and medial malleoli
Pathology shown	Fractures, dislocations
Radiographic Anatomy	Ankle Radiographic Anatomy
IR Size & Orientation	24 x 30cm Landscape, divided in two usually fits two ankle projections, use lead masking for unused area
Film / Screen Combination	Detail (CR and DR as recommended by manufacturer)
Bucky / Grid	No
Filter	No
Exposure	60 kVp 3.2 mAs
FFD / SID	100cm
Central Ray	Midway between the malleoli Perpendicular to the IR
Collimation	Centre: Tibiotalar joint Shutter A: Open to include the distal 1/3 of the fibula and the proximal metatarsals Shutter B: Open to include the lateral skin margins
Markers	Distal and Lateral Marker orientation AP
Shielding	Gonadal (check your department's policy guidelines)
Respiration	Not applicable
Positioning	Patient's leg fully extended Lower leg in AP position, dorsiflex foot Internally rotate entire leg and foot 15 degrees until the malleoli are equidistant to the IR, that is, they are parallel to the IR (this usually brings the little toe directly over the centre of the heel)
Critique PACEMAN	Positioning The correct positioning is evidenced by The lateral and medial malleoli are shown in profile There is some minor imposition of the distal fibula over the tibia There lateral mortise space is open, as there is no superimposition of the talus over the fibula The tibiotalar joint space is open Area Covered Distal 1/3 of the fibula and tibia, lateral and medial malleoli, talus, proximal metatarsals, soft tissue and skin margins of the ankle Collimation Centre: Tibiotalar joint Shutter A: Open to include the distal 1/3 of the fibula and the proximal metatarsals Shutter B: Open to include the lateral skin margins Exposure Bony trabecular patterns and cortical outlines are sharply defined Soft tissues are visualised
Special Notes	The effect of too little leg and foot rotation The lateral mortise will be closed The medial mortise will be open The effect of too much leg and foot rotation The image will look more like an Oblique Ankle view, that is The medial mortise will be closed The sinus tarsi will be shown