Indications for imaging
Trauma, degenerative conditions, bone pain.
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Anatomy Demonstrated
Ankle joint, distal tibia and fibula and proximal tarsal bones,
lateral calcaneum.
Ankle Lateral Rt Anatomy
Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy
Saunders, London
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Basic Patient Position
The patient lies supine on the table legs extended, long axis of
the limb in line with the long axis of the table, the foot is
dorsi flexed to bring the plantar aspect 90 to the film.The
patient then rotates externaly onto the affected side and flexes
the knee slightly to aid stability, a small pad under the knee
will aid correct positioning.
The postion is correct when the tibial and fibula malleoli are
not in vertical alignment but with the tibial malleolus
approximately one centimeter anterior to the fibula malleolus
approximately. Note that the foot is extremely mobile and
rotating the foot externaly may not rotate the tibia and fibula,
when rotating the ankle the whole leg has to be rotated.
Ankle Lateral Rt Patient Position
Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy
Saunders, London
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Radiation protection
Direct lead rubber gonad protection using a "half
apron".
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Central Ray
The vertical central ray is centered to the medial malleolus.
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Exposure Factors
| Kv |
mAS |
FFD (cm) |
Grid |
Focus |
AEC |
Cassette |
| 60 |
5 |
100 |
No |
Fine |
No |
18 x 24 cm |
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Evaluation of the Image
ID and markers must be present and correct in the appropriate
area of the film
Evidence of collimation on four sides equally around the
centering point.
Limits of the examination, superiorly the distal tibia and
fibula, inferiorly the calcaneam anteriorly the navicual and
posteriorly the skin surface over the calcaneum.
The joint space should be open and of uniform width, and the
fibula malleous will appear superimposed on the posterior half
of the tibial malleolus.
Optimal exposure should penetrate all the bone structures and
contrast should be low enough to visualise fully the bone and
soft tissue structures.
Ankle Lateral Lt. Radiograph
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Related Projections
Ankle AP and oblique
Tibia and fibula AP and lateral.
Tarsal bone projections.
Foot DP and DP Oblique.
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Additional modalities
CT
MRI
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