Sure you can do it, as I said, you just squash and stretch a bone, and the images attached to it will go along.
You can test bone scaling and shearing in the Spine trial to get a feeling of how it would work.
If you have a look at this page: Tools - Spine User Guide: Scale tool
Some stretching is in action on a single bone:
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If you open the first link I posted of the examples, a lot of squash and stretch is going on on the dog various parts such as the eyes.
Of course, you can push it even more to the extreme (: test it out!
