Need help diagnosing chicken - foot issue (PICS ADDED!!)

My chicken has been limping for a couple of weeks now, and can hardly walk at this point.

At first I figured it was a sprained ankle, but upon closer inspection the bottom and sides of her middle toe area are enlarged. The bottom pad on that area of the foot is enlarged, but not really discolored and with no scab. Also, the sides of the enlarged area are hard, not soft.

Poking/squeezing the area does not seem to bother her at all. In fact I cannot do anything to the leg/foot that makes her recoil, so it seems odd that this is keeping her from walking.

I poked a syringe into the bottom of her foot but was not getting any pus, just a tiny bit of blood. If it were bumble-foot, would the pus be flowing easily or is it thick?

I'll probably order some antibiotics next, but it would be nice to rule out bumble-foot right now if I could. I'll try to post a picture tomorrow.

She is close to 15 years old, by the way, so I'm not discounting arthritis or joint degeneration. Maybe the foot is just a coincidence?
Thanks for any help!

EDIT:

Here are some pictures.

Bad foot: Notice the enlarged middle toe.



Top view. You can clearly see the middle toe area is enlarged. The sides are hard it almost feels like a bone growth.



What the other one looks like. (Bad one is on the right)


Another comparison picture.


Any ideas?

 

OK, I added pictures. There is a little black speck on the bottom of her foot rather than the toe (which is also a little larger than normal) but it could just be some discoloration? You can sort of see it in the pictures.

 

Well, as you can see in the big picture below, there is a black dot.. but it looks more like discoloration and there are several similar ones on her feet. Isn't the bumblefoot usually more of a dark scab?

Regardless, I think chickenlady has talked me into a round of antibiotics for now. Any more opinions would be much appreciated. Thanks everyone!

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