Sesamoids

Question 1

Lewis Method (Tangential Projection)
Part Position

Answer 1

• Prone (uncomfortable and often painful)
  Part Position:
• Dorsiflex and rest great toe on table
• Ball of foot perpendicular to the horizontal place
• Plantar surface of foot forms about
  15°-20°angle from
  vertical
• Elevate a ected
  ankle on sandbags
  (if needed)
• IR centered to 2nd
  metatarsal

Question 2

Lewis Method (Tangential Projection)
Central Ray

Answer 2

Perpendicular and tangential to 1st
MTP joint

Question 3

Structures Shown

• Tangential projection of the
  metatarsal head in profile and the sesamoids

Answer 3

Lewis Method (Tangential Projection)

Holly Method (Tangential Projection)

Question 4

Projections for Sesamoid

Answer 4

Lewis Method (Tangential Projection)
Holly Method (Tangential Projection)
Causton Method (Tangential Projection)

Question 5

Holly Method (Tangential Projection)
Part Position

Answer 5

• Seated (more comfortable for the
  patient)
• Elevate a ffected ankle on sandbags
  (if needed)
  Part Position:
• Dorsiflex and rest great toe on table
• Adjust foot so that medial border is
  vertical
• Plantar surface form
  an angle of 75o with plane of film

Question 6

Holly Method (Tangential Projection)
Central Ray

Answer 6

Perpendicular and tangential to 1st
MTP joint

Question 7

Causton Method (Tangential Projection)
Part Position

Answer 7

• Lateral recumbent on una ected side
  Part Position:
• Limb partially extended
• Foot in lateral position
• First MTJ perpendicular to the horizontal plane of the IR

Question 8

Causton Method (Tangential Projection)
Central Ray

Answer 8

• Prominence of the MTJ at 40° toward
  the heel

Question 9

Structures Shown

•Sesamoid bones projected
axiolaterally with a slight overlap

Answer 9

Causton Method (Tangential Projection)