Pelvic Spinography

Question 1

How can we evaluate leg length on films (if we have them)?

Answer 1

Femoral head line (compare levels)

Scanogram (hip, knee and ankle joints) to give the most accurate representation of actual leg length

Question 2

How can we determine AP pelvis on films?

Answer 2

Femoral head line (ideally horizontal)
Intercrestal line (ideally parallel w/femoral head line)
Sacral base line (ideally parallel to 2 above)

Question 3

What should be noted about the level of L5 and its relation to the intercrestal line?

Answer 3

If L5 intersects or falls ABOVE the intercestal line, it is more susceptible to disc herniation or degenerative changes than L4.

If L5 sits below the line, L4 is more susceptible.

Question 4

How do we measure pelvic malpositions on films?

Answer 4

Ilium misalignments (flex/ext malposition)
Internal and external malpositions

Question 5

What is confusing as fuck about internal and external malpositions?

Answer 5

Gonstead calls in external malposition an IN because the PSIS are internally rotated toward one another. Equally confusion, the internal malposition would be an EX by Gonstead because the PSIS have rotated externally.

Question 6

How do we measure sacral misalignments on film?

Answer 6

Sacrum evaluation of 2nd tubercle to sacral ala
Sacrum evaluation of lateral flexion using sacral base line and femoral head line (may converge on side of lateral flexion)

Question 7

Why would we take films of the pelvis?

Answer 7

To rule out pathologies and/or injuries rather than to provide diagnostic information about SI syndrome

Question 8

Do we take xrays to analyze the SIJ for malpositions?

Answer 8

No! UNACCEPTABLE!