Radiographic Examinations of the Sesamoid Bones
1. LEWIS METHOD
2. HOLLY METHOD
3. CAUSTON METHOD
• Patient in prone position
• Dorsiflex the foot so that plantar surface of foot forms about 15°-20° angle from vertical
• Dorsiflex the 1st digit (great toe) & rest on cassette to maintain position
• Ball of the foot perpendicular to IR.
CENTRAL RAY: Perpendicular and tangential to the 1st Metatarsophalangeal joint.
• Visualized Metatarsal head.
• Demonstrate possible fracture of the sesamoid bone.
• Uncomfortable and often painful position for the demonstration of the sesamoid bone.
• Patient in supine/seated position
• Adjust foot so that medial border is vertical
• Plantar surface form an angle of 75° with plane of film
• Patient hold toes in a flexed position with strip of gauze bandage.
CENTRAL RAY: Perpendicular to the head of the 1st metatarsal bone.
• Patient in lateral recumbent position on the unaffected side & flex the knee
• Partially extend the extremity being examined & put sandbag under knee & foot
• 1st metatarsophalengeal joint perpendicular to horizontal plane of IR.
• Place cassette under the distal metatarsal region
CENTRAL RAY: Directed to the prominence of the 1st MTP joint at an angle of 40° toward the heel.
•Oblique position separates the shadow of 1st MTP sesamoid
• Sesamoid bone projected axiolaterally with a slight overlap.