"The doctors are saying she has some fractures around her face but it looks like there is no fractures in any other parts of her body.
"So we have been told to wait to see what happens in the next 12-24 hours but at this stage she doesn't need an operation."
The accident was extremely unusual in that it happened after the trial had been run and the horses were slowing down to turn around and return to the stables.
Myers's mount ducked sideways, she was dislodged and the horse following her struck her.
Trials are conducted under race-like conditions to educate horses or improve their fitness and the Racing Integrity Unit steward in charge of the meeting Neil Goodwin said the incident was minor in how it unfolded but Myers was simply unlucky.
The winner of 650 races in New Zealand alone, Myers is a respected senior member of the jockey's ranks.