What is on my chicken's foot?

[musicalchicken]

I have noticed lately that one of my chickens has been limping. I looked at the bottom of her foot and saw a huge bump with dirt or blood right in the center. It looks like a big ball of dirt at the bottom of her foot,but I am still not sure what's wrong. How can I help her? Would this require some type of backyard surgery or do I need to take her to a vet? Any help would be appreciated, thanks.

 

[Scott H]

Search "bumble foot" and see if it looks like that. ...

 

[Eggcessive]

click on this link for a good picture and info about bumblefoot: http://www.the-chicken-chick.com/2011/07/bumblefoot-causes-treatment-warning.html