[QUOTE=Lady Eboshi;7965989]
My understanding of “hunter’s bump” is ossification of the SI joint caused by wear and tear, usually after years of jumping. Most often it’s fused and considered a blemish more than an unsoundness.
Goose-rumped is conformational, more common in certain breeds, and while it may be somewhat performance limiting at the higher levels, is not considered an unsoundness either.
I frankly don’t notice either one looking at your horse in that picture–she looks like a PEACH! :)[/QUOTE]
This. Usually, a hunter’s bump is before/on the sacroiliac joint and is usually an indication of compounding trauma. Riding, training, jumping, etc. It is the ossification of the SI joint.
A goose rump is different, it is the way the horse is formed and is not a result of training or trauma. It is the angle of the sacrum where the sacral spines (S1-S5, IIRC) are steeply sloped in length. Here is a good picture for illustration, in which the second sacrum was likely belonging to a horse with a steep croup:
http://www.equisearch.com/content/content/20399/Figure-1-300x277.png
btw, your mare is friggin’ adorable. I would say she is goose-rumped, not a horse with a hunter’s back.