There were fears he had fractured his hip, but they proved unfounded. Casey was given extensive X-Rrays and an MRI scan, concentrating on his pelvis and neck, at Blanchardstown Hospital in Dublin.
Fortunately, they revealed absolutely no spinal involvement and the rider will make a full recovery in time.
He will remain in Blanchardstown for the next few days and faces another long period on the sidelines.
The unlucky Casey broke his leg at Wexford back in November, but made a spectacular return at Leopardstown in February
He partnered Rule Supreme to land the Grade One Hennessy Cognac Gold Cup and was aboard the nine-year-old as well when they finished a creditable third behind Inglis Drever and Barcacouda in the Ladbrokes' World Hurdle at the Cheltenham Festival.