To be honest, I didn't even know what it was until a few weeks ago.. and I was looking at my mare the other day and noticed the little dip upwards right before her hindquarters, and I've been paranoid since.
She is VERY out of shape at the moment, all summer I just haven't had the time to ride her, and since she is on 24/7 pasture she has never been "cooped" up. Since hurricane Irene blew threw, our grass just exploded, and I've let her take advantage of it before it gets cold and all that nice grass dies off.
But is it possible that because she is so out of shape, and has almost no muscle build at all at the moment, that's why her butt is so.... sunken? I'm not sure... I wanted to see what other people thought. On the few occasions we did get out, she showed some discomfort and stumbled a few steps, but I gave that due to the fact she is like I said- so out of shape.
And don't worry... with school off for a bit, Indie and I are going to be hitting trails again soon LOL.
Any input is greatly appreciated, Thanks guys ♥