Navicular or......?

["guest@endurance.net" <guest@endurance.net>]

Diana Regendanz di@calm.com
Someone in my barn has a 17 plus quarter horse plus ? (she says Arab but I kinda doubt it).  When he was given to her he had been neglected, tail and mane full of burrs and flat feet that hadn't been trimmed for quite some time.  They were quite broken but after some months and careful trimming looked a whole lot better but he wasn't sound.  Vet #1 took X-rays said he didn't have navicular but had white line disease.  He had no more white line disease that pigs can fly.  Eventually persuaded her to consult another veterinarian who blocked the horse as well as taking X-rays which showed navicular in the right front foot.  Bar shoes and leaving the heel longer helps but he's stil off and on lame, more often "on".  Being summer he's out 24 hours a day and she also rides him and adds Glucosamine to his feed.  At the last shoeing she insisted the farrier leave his heels even longer than before (I don't think he took anything off.  Four weeks later and the hoof appears to have over-grown the shoe and he's really lame today when I brought him in from the back field.
The X-rays were taken over one and a half years ago but she took them to another veterinarian just to look at them for a second opinion.  This vet. came back said that it ws not navicular but either a bubble in the X-ray or a CYST in the foot.  She never saw the horse or his way of going.  He's a dear horse but very heavy on the forehand and carries much too much fat especially on the shoulders and is generally ridden witha Western saddle.
After all this explanation my question is has anyone ever heard of a cyst being present in the foot?
Would really appreciate any opinions.  Thanks.