Geez, I just hate being the bumblefoot expert. Guess I'm really not because I'm still dealing with it in a couple of birds that seem to have it perpertually. I think Violet will eventually die from it if it goes systemic. She's had it about half of her life, poor girl.
Lee, it looks like it is probably the beginnings of bumblefoot. In
general, they don't get callouses. Before I go further, when you do anything around this, wear rubber gloves if you have them-this is a nasty staff infection and can cause things like that flesh-eating stuff you see people get. Be very careful and do not get it on you, sterilize all instruments and your own hands!
The only thing you could do since it doesn't look like it's gotten bad is to wrap the bird in a towel so she can't struggle, clean the foot with alcohol or betadine then use a sterilized xacto knife to carefully cut sort of sideways around the callous thing and lift it out. You may find a little bit of solidified pus or liquid infection or nothing. Then you need to put a piece of gauze soaked in tea tree oil or just some antibiotic ointment and bandage the foot to keep bacteria out of it. You'd change the dressing about every other day or so till it seems healed. There's stretchy vetwrap or you could cut up an old clean sweatshirt into bandages like I did and use medical tape. You wrap between the toes, avoiding the back toe, and around the leg. Just make sure all toes are loose and can move.
If it was really bad swollen, I wouldnt put the ointment, though, because it seals up the wound too much, but would flush the wound with a sterile saline solution after you get as much infection out as you can. Your girl's doesn't look bad right now and you may have caught it early enough. I've packed wounds with gauze soaked in saline solution then covered with dry gauze (wet-to-dry dressing), then the next day, you pull that gauze out and it debrides the wound and brings infection out with it. You do that over and over and over till you're sick of it and eventually, you'll see new pink tissue forming and the swelling going down. Tea tree oil seems to help almost as well as any antibiotic ever did-I quit giving Violet antibiotics because she's had almost every one made two or three courses and she ought to glow in the dark by now. I won't give her anymore.
Let me know how it goes! Here is a link to treating bumblefoot:
http://www.featherfanciers.com/forums/showthread.php?t=58