Indeed good luck with translating that, I think I do get its meaning though.
One way would be to describe the meaning of those words.
I will take a shot at this one; I can't take any liability to the accuracy of this.
![Cheesy :D](https://forum.eurofurence.org/Smileys/default/cheesy.gif)
"arm" meaning both arm as well as poor(ly), and "bein" means leg
And "besser dran" meaning better off, but also means something like better attached.
"dran" also means something like ~at it~ as in "du bist dran" its your turn.
"bein ab" means something like, leg detached (apart).
So there actually are several translations possible, that's also the irony in it.
Phew,
![Tongue :P](https://forum.eurofurence.org/Smileys/default/tongue.gif)
I hope that helps.