Lower Limb (Pediatric) Projections

Patient Preparation

• Explain the procedure gently to both the child and guardian.
• Remove any clothing, shoes, or metallic objects from the area of interest.
• Immobilization aids or parental assistance may be used for comfort and to prevent motion.
• Use appropriate pediatric exposure settings and lead shielding.

BASIC PROJECTIONS

1. Anteroposterior (AP) Projection — Lower Limb

Positioning:

• Infant or child supine on the table.
• Both lower limbs extended.
• Feet dorsiflexed so that the plantar surfaces are vertical if possible.
• Center both limbs to the midline of the image receptor (IR).

Central Ray (CR):

• Perpendicular to the IR.
• Directed to the midpoint of the lower limbs.

Collimation:

• Include both hip and ankle joints.

Evaluation Criteria:

• Entire lower limb visualized from hip to ankle.
• No rotation — femoral condyles and tibial plateaus symmetric.
• Both joints (hip and ankle) included on the same image when possible.

2. Lateral Projection — Lower Limb (Mediolateral)

Positioning:

• Child lies on affected side.
• Opposite leg positioned behind for support.
• Slight flexion of the knee for stability.
• Ensure true lateral alignment — femoral condyles superimposed.

Central Ray (CR):

• Perpendicular to the IR.
• Directed to the midpoint of the lower limb.

Collimation:

• Include both knee and ankle joints.

Evaluation Criteria:

• Entire tibia and fibula visualized.
• Superimposed femoral condyles.
• Knee and ankle joints clearly demonstrated.

OTHER PROJECTIONS

3. Congenital Clubfoot (Talipes Equinovarus) — AP and Mediolateral

Positioning:

• Infant or child supine for AP view or on the affected side for lateral (mediolateral) view.
• Foot placed in its natural deformity — do not force correction.
• Center the foot or ankle to the IR.
• Use both AP (dorsoplantar) and mediolateral positioning as appropriate.

Central Ray (CR):

• Perpendicular to the IR.
• AP: Directed midway between the malleoli.
• Mediolateral: Directed to the midpoint of the foot.

Collimation:

• Include entire foot, ankle, and distal tibia/fibula.

Evaluation Criteria:

• Visualization of talus, calcaneus, and midfoot alignment.
• Foot anatomy shown without distortion.
• Both AP and mediolateral views demonstrate the congenital deformity.

Image Evaluation Checklist

• Entire lower limb or foot visualized as required.
• Correct exposure for pediatric anatomy.
• No motion or blurring.
• Anatomical markers correctly placed.

Common Pathologies Demonstrated

• Congenital clubfoot (talipes equinovarus).
• Leg length discrepancies.
• Fractures or developmental bone deformities.
• Growth plate (epiphyseal) abnormalities.