Pain creates panic. Our horses are prey animals. As such they are masters at hiding pain. The weakest horse in the herd gets eaten. By the time your horse is expressing lameness or undesirable behavior due to pain, they have been in pain for a long period of time (unless it is a traumatic injury). If they are exhibiting changes in body use, gait and hoof morphology, the pain has been there and hiding for awhile. Having recently had surgery with uncontrollable pain, I can attest to the helplessness and panic that is experienced mentally. So imagine if your horse that is bucking, rearing, bolting, spooking, etc is actually dealing with pain that has not been addressed. The constant discomfort has triggered their survival response and the behaviors we see as undesirable. These behaviors are actually panic and not being able to escape the discomfort. Sometimes these pain behaviors are not long term pain issues but instead pain associated with an activity. If being ridden is creating acute discomfort from tack or technique, the horse will revert to panic and anxiety each time they are presented with that activity.