Which structure is contacted for all PI listings?

• A. Sacral base
• B. Inferior PSIS
• C. Acetabular ridge
• D. Lateral PSIS

Answer: (B)

For all PI listings, the contact point is the inferior PSIS. The innominate adjusts target the pelvis as a unit, and the inferior edge of the PSIS sits at a reliable, accessible location on the ilium to apply the thrust. Using the inferior PSIS provides a stable, consistent contact that directs the vector through the ilium and SI joint in the desired way, regardless of the specific PI variation being addressed.

Choosing a sacral base contact would shift the focus to the sacrum itself, not the innominate, which isn’t the goal for these listings. The acetabular ridge sits near the hip socket and isn’t the intended contact for pelvic listings. The lateral PSIS is less optimal for delivering the standard PI vector and can misdirect the thrust. So, the inferior PSIS is the most appropriate, consistent contact for all PI adjustments.