This lameness happens about once a year in the fall. At least five years ago, I took him to one of California's premier equine hospitals, Alamo Pintado. After extensive tests, Dr. Carter Judy felt that it was either an injury to the collateral ligament or a deep bruise. My own vet confirmed those two options, while my farrier seems certain it's a bruise. Either way, the solution is the same - time off.
After many years of the same pattern, I think I finally have a reason for why it happens. During the summer, I am at the barn every day in the early morning. I am a teacher and have most of the summer off. Speedy knows my schedule and looks forward to my visits.
In all of the pacing and whirling he does, he inevitably whacks his own front feet, usually the right one, and comes up lame. The soreness will be quite pronounced the first day, but over two to three weeks it simply fades away.
My fingers are crossed that he really is sound and stays that way. I have all week to reassure him that life is still worth living and that he hasn't been forgotten. Arabians are just too darned attached to their people.