PI subluxation leg length?

• A. Lengthens
• B. No change
• C. Shortens
• D. Rotates

Answer: (C)

In innominate misalignment, a posterior-inferior (PI) ilium changes pelvic height on that side enough to alter how long the limb appears. A PI position means the ilium sits back and down, which tilts the pelvis and effectively shortens the functional distance from the hip to the ankle on that side. So the leg on the PI side is measured as shorter. This is why the correct choice is that the leg length shortens. Lengthening would be expected if the pelvis on that side rose (an anterior-superior pattern); no change would imply no pelvic tilt; rotation alone doesn’t produce a straightforward leg-length discrepancy.