For those making suggestions…this thread is 9 years old. The op hasn’t logged into this forum at all for a few months.
@Mandahope you’ll have a better shot at reaching pj if you PM her.
The vet will shave the bulb of the heels and the back of the pasterns with a #40 blade, looking for a surgical scar. This needs to be done on both front legs since a horse might have had only one hoof heel nerved.
it is very nowadays to nerve the entire hoof. Very rare because it is very dangerous to ride a horse which cannot feel its feet,
When I read the symptoms, my first thought was “spine”. A badly fitted saddle can pinch the spine. So can kissing spine or arthritis of the spine. Add that to your list of things to consider. 
