The Irishman was catapulted to the turf from the pacesetting Abbyssial at the second flight in the Triumph Hurdle. He was taken to hospital after sustaining a compound fracture to his right humerus, officials at the racecourse said.
Walsh, who was due to ride On His Own for trainer Willie Mullins in the showpiece Gold Cup steeplechase (1520), is now set to miss next month's Grand National meeting at Aintree.
Walsh, 34, has ridden 41 winners at the Cheltenham Festival, including three this year.
- Willie Mullins
- compound fracture