On Left Iliacus function…

How will the left iliacus act as an internal rotator on the left?  I have it working bi-planar for IR on the frontal plane and flexion on the sagittal plane.  I am thinking this occurs based on the forward (anterior) and ER positioning of the ilium on the femur in standing but I still have difficulty seeing the IR there.

The left iliacus acts as an AF IR stabilizer on the left.  It’s acting as an AF motion, not FA.  The left iliacus doesn’t perform AF IR, it stabilizes you there once you are shifted into AF IR.