what is a horse sacroiliac
by Erin Hackney, CEMT. Sacroiliac pain is a common occurence in horses and can be a primary or secondary source of pain causing acute or chronic lameness. The affected area is the sacroiliac joint of the horse's lower back/pelvis, and its surrounding structures.ack pain in horses is usually considered a secondary, symptomatic issue caused by the horse compensating for injury in a limb-while sacroiliac injury can be a primary source of pain.