Not sure what the question is. IK applies to the ends of limbs (Feet,Hands). The Hip is the other end of the Leg IK chain so you turn off the IK for the legs which by extension turns off the IK of the hip. The IK on hands usually ends at the neck. SO you can move either end of the chain and get movement, but none of the parts in between. Also you can create your own IK chain and define a new start and end point.

Poser 5, 6, 7, 8, Poser Pro 9 (2012), 10 (2014), 11, 12, 13