The interesting part is the left hind foot!
And now... just because it's so **** interesting...
Trauma/abscess at coronary resulted in prolapse of corium tissue. The tissue took a blood supply along for the ride so continued to grow. Vet had tended original trauma and thought all would be fine. That was five weeks ago. Oops!
Permanent damage to coronary corium will mean this horse will present compromised dorsal hoof wall; probably permanent condition.
I left the "unicorn horn" for the vet to deal with since the blood supply was active.
One just never knows what we may encounter out there.