Ok, quick background on horse: 10 YOA Appy, Broodmare until 8. In pretty regular work at this time, mostly long distance trail and trail obstacle work. Horse seems in good health. Fed Alfalfa-Oat/Alfalfa-Bermuda pellets, 3-way/Timothy/Alfalfa hay free choice, carrots, occasional peaches, vitamins. Horse is well hydrated.
Noticed yesterday that she was objecting to touch on the off-side of her neck. When touched with the lightest touch, she will fling her head and come forward. On-side of neck has no problem. Normally I can touch her everywhere without protest.
Noticed that there is an area on her neck that appears "corrugated." Skin is tightly contracted over area. I can touch above or below this area, but ANY touch immediately adjacent or within area causes pain reaction. Area is about 10" behind her head.