Huge hard mass under anus -- NOT melonoma

[zhorse]

OK here's a new one for me. My sweet boy had stifle surgery with great success and then headed to training a few months later. I bring him home from training and he is covered in bites and kicks around his hind end. I brush him and look under his tail to see a triangularly extended "lump" with a small scrape on top.

I hate to ask a terribly stupid question, but...Did my horse break his ass? I mean the "lump" is so hard and oddly shaped that it doesn't just feel like swelling.

Help!!!!

[TrueColours]

Well ... if there is heat and tenderness, I'd vote for an abcess that hasnt burst yet and if it is cold and hard with no tenderness I'd vote for a hematoma ...

Poor guy!!!

[GatoGordo]

Either way, if he'll let you apply heat (like hosing with warm water or holding a hot, wet towel on it), it should help the lump either drain or disappear faster.

[FindersKeepers]

It could be a cyst or abcess. If its hard, it's ready to pop. I'd try warm compresses and see if you can get it to open up. If it doesn't drain, or God forbid gets bigger, have a vet come look at it. It could be something like a foreign body that needs removes and a course of antibiotics.