Chick zipped 90% for over 24 hours. Finally helped a bit, still couldn't push out. Yolk well absorbed, pulled shell open, still couldn't push. Got him/ her out, belly down to rest. Left leg won't straighten. Got him in a chair with vetwrap, but it's not helping. I don't think it's a popped tendon, cannot straighten it. Cannot force it (the slightest pressure seems to hurt) However, having teeny bit of pressure gradually increased over the day it has gotten the smallest but better. Ie: he can sit upright now on his own. Any advice? Anyone seen this before? There's another chick that hatched by itself that has one foot that looks normal but doesn't want to use it. Potential temp/humidity problems in this hatch. Never had these issues before.