How to eliminate stretching?

How can I get a warp independent object from stretching when using a draggable handle?  For instance, let's say I have a forefinger that I want to move independently of the hand using a draggable handle (pivot point at the base of the finger, handle placed at the tip), but I don't want its length to stretch at all.  It's okay if it "bends" left and right at midfinger, like a knuckle.  I just don't want it to stretch beyond the height value that I gave it in AI.  How can I accomplish this?  Here is a screenshot of the problem.