Ankle Medial (Lateromedial) is a radiography positioning projection of the Lower Extremity. Patient lateral on non-affected side, medial ankle on IR. CR perpendicular. SID 40". The centering point is located ankle joint space with medial border of foot on ir.. The central ray is perpendicular to the ankle joint with medial border on ir.. Image-quality criteria include ankle joint space open in medial oblique projection., medial malleolus and medial ankle joint space clearly demonstrated.. Standard exposure ranges from 60 to 70 kVp, 4 to 7 mAs, at an SID of 40 inches (102 cm).
Anatomy demonstrated
- Medial malleolus clearly demonstrated.
- Medial ankle joint space open.
- Talocrural articulation visible.
- Distal tibia and fibula in near-lateral position.
- Talar dome and dome margins.
- Head and medial process of talus.
Patient preparation
- Verify patient identity using two identifiers.
- Remove footwear, socks, and any radiopaque foot jewelry.
- Position the patient lateral recumbent on the non-affected side.
- Turn the affected foot inward (medially) with medial border on IR.
- Flex the knee and position foot at 90 degrees to the leg.
Position & centering point
Ankle joint space with medial border of foot on IR.
Central ray
Perpendicular to the ankle joint with medial border on IR.
Exposure / technique
- kVp
- 60–70
- mAs
- 4–7
- SID
- 40" (102 cm)
- Notes
- Position patient on non-affected side. Flex affected knee for anatomical stability.
Image-quality criteria
- Ankle joint space open in medial oblique projection.
- Medial malleolus and medial ankle joint space clearly demonstrated.
- Talocrural articulation open without excessive overlap.
- Distal tibia and talus well visualized.
- Bone trabeculae sharp, no motion blur.
- Collimation: 1 inch on all sides of ankle, 8 inches lengthwise.
Common errors / ARRT traps
- 1 Insufficient medial rotation fails to open the medial ankle joint.
- 2 Excessive medial rotation closes the talocrural articulation.
- 3 Off-centered CR clips the medial malleolus or ankle joint.
- 4 Plantar flexion or dorsiflexion tilts the ankle mortise.
Clinical indications
- Suspected medial malleolar fracture.
- Evaluation of deltoid ligament injury or medial ankle stability.
- Assessment of talonavicular articulation.
Aligned to the 2025 ARRT Content Specifications.