My mare (pony/arab, 13.2 hh, 12 years) has reasonably good conformation except slightly croup high, but has a hatchet neck (we guess because she was put in draw reins at an early age).
Have recently started to school her, after only using her for hacking, as we now have access to a good out-door school. Are there any techniques in schooling, or other therapeutic methods, which can help with this?
Margareth, at risk of sounding flip....ALL the techniques that are those that have been advocated here for a decade will help....beginning with twirling the head. The raising of the base of the neck is one of the primary goals of training, no matter what the conformation of the horse.
If "raising the base of the neck" is obscure to you, then I suggest you go over to the Knowledge Base section of this website and study first "Lessons from Woody" and second its sequel, "True Collection". Head-twirling is one of the central themes, moreover, of my book "Conquerors: The Roots of New World Horsemanship."
You will also benefit from reading the currently-active thread "Help for Kissing Spine", where I have been giving point-by-point lessons on axial body functioning of the horse. -- Dr. Deb