Yeah, theres not much I can think of to do either. My gelding, which has good hard feet also came up dead lame due to that darn frozen mud. Tripping and tippy toeing. I just try to keep him out of the nasty stuff. Its supposed to freeze again this weekend and Im planning to put shavings around the water trough to help with that and Ill be feeding him out away from where the mud is. His poor soles are black and blue.
Also FYI for people that don't know, their urine in snow can look red, so don't freak out like we did. With him walking funny and it looking like he was peeing blood, it was an interesting scare as its the same horse we almost lost a couple of months ago. Good thing to know. :)