This just in form the NTRA; if you follow horse racing, you know that this is a huge loss to the sport:
2006 HORSE OF THE YEAR INVASOR RETIRED DUE TO INJURY
Invasor, the 2006 Horse of the Year, was retired today due to a cracked sesamoid bone in his right hind leg. The injury was detected following a workout at Belmont Park this morning in which Invasor worked five furlongs in :59 2/5. The injury is not life threatening, and Invasor will retire to stud at Shadwell Farm in Lexington, Ky.
"I feel honored and privileged to have trained Invasor for Sheikh Hamdan," said Kiaran McLaughlin, trainer of Invasor. "He feels so bad for all of us connected with the horse. He's a great owner and a great sportsman. It's a very sad day for all of us. Invasor was a superb horse and a pleasure to be around. Everyone on my team did a great job with him, as did jockey Fernando Jara. It's a shame the way it ended, but at least he will be able to go to stud."
"He came back fine from the workout," McLaughlin continued. "But when we went to wash his feet, he took a couple of funny steps and we noticed some swelling in his right hind leg. We had him x-rayed shortly thereafter, and that is when the fracture was detected."
Invasor captured the Breeders' Cup Classic - Powered by Dodge last year at Churchill Downs en route to 2006 Horse of the Year honors. He won two races from as many starts in 2007, taking the Donn Handicap at Gulfstream Park in February and the Dubai World Cup at Nad al Sheba in March. He had been scheduled to compete in the June 30 Suburban Handicap at Belmont Park.
Blogger's Note: The trainer did not specify which sesamoid bones were cracked but he surely was referred to the proximal (think: proximity, or closeness) sesamoid bones, which are like two walnuts located at the back of the fetlock, between the long pastern bone (P1) and the cannon bone, which is the straight up-and-down bone leading to the hock, in the hind leg. The fetlock area is more or less like the horse's ankle (human and equine anatomy doesn't exactly match up). The sesamoids act to regulate the tension of the tendon running down the back of the leg, as it changes direction.
The proper name for the navicular bone, inside the foot, is the distal (think: "distant") sesamoid; it helps the deep digital flexor tendon make a smooth pull to flex the foot. The words proximal and distal differentiate the sesamoids from each other and refer to the relative distance from the horse's head.
Invasor was lucky to have such a mild fracture. You may remember that two weeks ago I was blogging about the death of race filly Ruffian, who smashed the sesamoids of her front foot in a match race in 1975. She didn't survive the surgery that attempted to save her life.
Photo of Invasor links to Dubai World Cup web site.