The injuries occured when her mount in a 11/2-mile race at Gulfstream Park, Florida, Saratoga Source, snapped his right foreleg and crashed to the ground. Krone fell to the track immediately and the horse appeared to roll over her.
Krone, winner of the 1993 Belmont Stakes and Gulfstream's leading jockey, was taken to the Memorial Hospital in Hollywood, Florida, where she was described as being "in fair condition".
"I'm OK, but I just can't hold the phone," Krone said from the emergency room. She said she was "comfortable" and in little pain.
Three other riders - Dave Penna, Heberto Castillo Jr. and Katy Sweeney - also fell but were unhurt and rode again later in the day.
Krone, the only woman jockey to win an American Triple Crown race, severely fractured her right ankle in a three-horse spill at Saratoga in Aug 1993. She resumed riding last May but was sidelined again in a fall when she required further surgery to remove two plates and 13 screws from her ankle.
Her mount, Saratoga Source, was destroyed on the track.