One tiny quibble - if her right wrist is nailed through the ankle the same way as her left one is, surely it should be visible?
Now this pic has been floating around since the later part of the Bush administration so I could cop out and say it's too long ago to say what my artistic decision was back then.
Or damn, they cruxed Elastogirl.
However back then Cruxfoundation was going strong with a lot of discussion of crux art as well as the mechanics of crux, and with many of my early scenarios I was aggressively exploring what I could get away with.
About 15 years ago I typed up a document explaining some of my 'artistic process' insofar as it deserves the word and so my memory is outsourced to that haha.
I did a number of studies for the scenario and one of them in that doc hints at what I might have been thinking.
It shows a similar scene from the back, where you
do see both arms.
(the girl is different as this was before I had settled on a look for her)
So the idea is that her body is twisted to some degree sideways, and one arm is more straightened out than the other which still has a bit of a bend at the elbow. And then it might just work. Or not.
Actually
@mp5stab picked up that rough sketch and developed it a bit (there are some subtle improvements in addition to coloration)
Apart from that it seems the pic has always expressed the concept of the situation effectively judging from the reactions.
As an artist working in 2D that is really what you're going for. There's no guarantuee everything in my pics will always work if you actually "Try This At Home" with real wooden posts, nails and girls...