The first phase of compound correction addresses which component?

• A. In
• B. Ex
• C. Pi/As
• D. Leg length

Answer: (C)

The first phase targets the pelvis, using the ASIS (anterior superior iliac spine) and PIIS (posterior inferior iliac spine) landmarks to level and balance the pelvic orientation. These landmarks reflect how the pelvis tilts in the sagittal plane, and correcting them sets a stable base for the rest of the spine and body to align properly.

Why this order makes sense: the pelvis is the foundation for the spine and the entire kinetic chain. If the pelvis is tilted or rotated, the spine, sacrum, and even leg-length readings can compensate, making later corrections less accurate. By neutralizing the pelvic position first, subsequent adjustments (to other parts of the spine or to address leg-length concerns) work from a correct baseline and are more effective.

The other components—internal/external directional changes or addressing leg length directly—are typically managed after the pelvis has been balanced, because they often reflect or are influenced by pelvic alignment rather than being the primary starting point.