That's happening because the bend zones for the legs influence the hip of the mesh as well... basically a child bone has zones of influence that affect the parent... in this case the movements of the legs will also affect anything attached to the hip...

Also... in some cases changing the name of the node won't change the internal name so you may have renamed it "LTHandle" (the name that shows in the scene tree) but internally it's still called lThigh... for the purposes of conforming items, DS uses the internal names not the displayed names to determine if an item conforms to a body part...

Just a couple thoughts on possible causes... I can't say for sure what the issue might be...