What is this lump?

[asterid]

Mare was vetted, nothing mentioned, so wasn't there on vetting or when I tried her.

Have noticed a swelling on rear right hind on the inside of her pastern. It is exactly between fetlock joint and coronet band.

Since researching, have ruled out sidebone, ringbone and windgalls (as on inside not rear)

What is it?

It is about 10p diameter, squishy and cold. No lameness. is a lump and at top of lump there is a small area of no hair, so presuming an injury? abcess? infection?

I have vet coming next week, but I am impatient! Thanks

 

[Box_Of_Frogs]

Windgalls are just joint fluid leaking out of a joint that is damaged in some way so they don't have to be on the inside. They can appear anywhere near a joint. Certainly does sound like windgalls. They don't themselves cause lameness but they are a visible sign that something is going on in the nearby joint that could be a problem.