Tibia and Fibula Imaging

Question 1

Tibia and Fibula exposure factors and rationale

Answer 1

55 kV - need high image contrast, minimal penetration required
100 mA - fine focus required for image detail, minimal chance of movement artefact
**0.05 s **- when used with 100 mA, gives required mAs of 5 for appropriate image density
No grid - minimal scatter

Question 2

Imaging techniques for tibia and fibula

Answer 2

**AP Tibia/Fibula **
- patient seated on table legs extended
- put into AP mortise position if possible
- malleoli equidistant and ankle dorsiflexed as possible
- centre between ankle and knee joint, if can’t fit onto IR, centre in middle of area exposed
- collimate ankle/knee joints, tibia and fibula, soft tissues

Lateral Tibia/Fibula
- may need to be done horizontal beam for trauma patients
- 2 projections required if patient too tall
- from AP, externally rotate leg
- ankle flxed, malleoli superimposed
- small foam pad under lateral border of foot
- if HB, keep in normal AP and shoot horizontal beam, can use chair to help abduct unaffected leg from view

Question 3

Shaft Fracture

Answer 3

can be simple, comminuted or open, fracture to the shaft of the tibia or fibula

Question 4

What projections for Shaft Fracture? Explain rationale for each

Answer 4

AP - see the fracture lines in the tibia and fibula, see if simple, comminuted, open

Horizontal beam Lateral - check for any anterior/posterior displacement of the fragments, patient likely unable to move

Question 5

Radiographic appearance of shaft fracture

Answer 5

simple, comminuted or open fracture lines in the shaft of the tibia or fibula

Question 6

Post operative tibia and fibula

Answer 6

metal bar is inserted into the leg to hold bone into place (intermedullary nail and screws) - not ideal for children as bones can’t grow

Question 7

What projections for Post operative tibia and fibula ? Explain rationale for each

Answer 7

AP - ensure nail is holding bone in place
Horizontal beam Lateral - check the positioning and alignment of the screws placed, patient can’t move

Question 8

Radiographic appearance of post operative tibia and fibula

Answer 8

• intermedullary nail with screws holding fragments of the bone in place

Question 9

External fixation

Answer 9

screws in the skin and metal bar framework on the outside to hold bones in place, easily removed which is ideal for children so bones can grow

Question 10

What projections for External Fixation? Explain your rationale for each

Answer 10

AP - to ensure framework is holding the bone in the correct places
Horizontal Beam Lateral - check positioning of the screws/nails in the skin and ensuring it holds bone in place, due to metal framework, patient can’t move

Question 11

Radiographic appearance of External Fixation

Answer 11

• presence of artefact, metal bar framework on the outside of the leg
• fractures that are being held into place

Question 12

Rickets

Answer 12

bone disease in children which occurs due to malnourishment and vitamin deficiency

Question 13

What projections for Rickets? Explain your rationale for each

Answer 13

Weightbearing AP - to see how bowed the legs are and if there are any fractures present
Weightbearing lateral - to see legs under pressure, check lat view of tibia and fibula

Question 14

Radiographic appearance of rickets

Answer 14

• legs bowed resulting in curved tibia and fibula

Question 15

Non-accidental injury

Answer 15

signs of abuse

Question 16

What projections for non-accidental injury? Explain your rationale for each

Answer 16

AP - mainly looking at soft tissue and if there are any fractures present
Lateral - checking alignment of joints and if there are any hidden fractures present

Question 17

Radiographic appearance of non-accidental injury

Answer 17

• possible fractures
• soft tissue swelling