Leg Length

Question 1

How to preform leg length or long bone measurement?

Answer 1

orthoroentgenography or scanogram
shows limb length discrepencies through individual exposures of each joint

Question 2

Exposure of Hips to Ankles?

Answer 2

SINGLE EXPOSURE OF COMPLETE LOWER EXTEMITY TO ASSES ALIGNMENT AND DEFORMITY

Question 3

How are orthoroentgenography/scanograms completed?

Answer 3

3 exposires of lower limb for measurement
Hip, knee and ankle joints
radiopaque ruler placed beside limb in collimated field
in orthoentgenography - single IR
in scanogram - separate IR
Can be bilateral - ruler between legs - center at level of joints

Question 4

Hip to ankle exposure?

Answer 4

varies depending on equipment
asses lower limb alignment
standing in anatomic position - shoes off
ASIS to ankles
SID: 180cm to 300cm

Question 5

Image Stitching - DR

Answer 5

Multiple images taken
Manual or automatic
- if auto: mark ASIS and ankles, hold exposure switch until all images are completed
- if manual: technologist moves tube between images
software stitches image together

Question 6

CT Sonogram

Answer 6

CT scout images of upper or lower extremities
consistently reproduced and low dose

Question 7

Full length low dose systems

Answer 7

used in some large children’s hospitals
DR or CR
Two x-ray sources and two IR’s - AP and lateral at same time