Calcaneus Lateral (Mediolateral) is a radiography positioning projection of the Lower Extremity. Patient lateral recumbent on affected side, CR perpendicular to calcaneus. SID 40". The centering point is located 1 inch inferior to the medial malleolus, with the lateral border of the foot on the ir.. The central ray is perpendicular to the calcaneus in true lateral projection.. Image-quality criteria include entire calcaneus visible in true lateral without rotation., talocalcaneal articulation clearly demonstrated.. Standard exposure ranges from 60 to 70 kVp, 4 to 8 mAs, at an SID of 40 inches (102 cm).
Anatomy demonstrated
- Calcaneus in true lateral profile.
- Calcaneal tuberosity in profile.
- Anterior process of the calcaneus.
- Talocalcaneal joint articulation open.
- Talar dome and neck.
- Medial and lateral ankle malleoli.
Patient preparation
- Verify patient identity using two identifiers.
- Remove footwear, socks, and any radiopaque foot jewelry.
- Position the patient lateral recumbent on the affected side.
- Place the affected foot on the IR with the lateral border down.
- Flex the knee slightly for patient comfort and stability.
Position & centering point
1 inch inferior to the medial malleolus, with the lateral border of the foot on the IR.
Central ray
Perpendicular to the calcaneus in true lateral projection.
Exposure / technique
- kVp
- 60–70
- mAs
- 4–8
- SID
- 40" (102 cm)
- Notes
- Position patient on affected side. Flex knee if needed for comfort.
Image-quality criteria
- Entire calcaneus visible in true lateral without rotation.
- Talocalcaneal articulation clearly demonstrated.
- Calcaneal tuberosity shown in profile.
- Anterior process of calcaneus clearly visible.
- Medial and lateral malleoli at the ankle joint visible.
- Collimation: 1 inch on all sides of calcaneus, include heel and base of 5th metatarsal.
Common errors / ARRT traps
- 1 Medial or lateral rotation distorts the true lateral projection.
- 2 Plantar flexion or dorsiflexion tilts the calcaneus.
- 3 Off-centered CR clips the tuberosity or anterior process.
- 4 Lifting the lateral border off the IR distorts the foot position.
Clinical indications
- Suspected calcaneal fracture or stress fracture.
- Evaluation of calcaneal spur or heel pain.
- Assessment of talocalcaneal articulation.
Aligned to the current ARRT Radiography Content Specifications.