Dear physiomitch:
You are not alone in trying to find information on a four sided pelvic bone position test. There is little on this type of testing. The OGI is doing a research project on it and a paper should be forthcoming soon.
I use a landmark test with the following comparison referenees: ASIS to ASIS. PSIS to PSIS, ASIS to PSIS (R&L) with hip abduction directly lateral in the coronal plane from closed foot stance to the maximum obtainable by the patient using 30 cm increments..
Any deviations should be significant. Normal is all landmarks level or even in the horizontal plane.
You can use a goniometer or eye sight. The differences will be greater than 1 cm in the ASIS comparisons and less in the PSIS comparison. ASIS differences are often in the order of 2 cm plus. PSIS usually are less .5 cm or sligthly greater.
Do not look for mm differences. The differecnes must be significant.
See if your results pre therapy and posttherapy are significantly different.
Hope that this is helpful.
Best regards,
Neuromuscular.