I haven't seen something like that. I did see ones shaped like a mushroom, so they put pressure on the frog. The ones I saw were for quarter cracks.
Im assuming these would be for frog pressure as well.
I feel as though it's a variation of heartbar shoes for all over pressure, both frog and sole. I imagine the horse has poor frogs and an issue with the sole that would make it sensitive (the name is escaping me at the moment D: ). Posted via Mobile Device
I've seen those used a lot with standardbred race horses. It is a bar shoe and, if I remember right, helps to distribute the impact on the whole foot to take the "sting" away. Standies race and train on pretty solid ground.