Bloomberg said Monday that his 27-year-old daughter was "fine."
Georgina Bloomberg suffered a concussion after falling during a tournament in Syracuse on Friday night.
The well-regarded equestrian was briefly knocked unconscious but walked out of the arena on her own.
Bloomberg said his daughter may have cracked some vertebrae. He said she was getting an MRI scan.
Speaking at a City Hall news conference, Bloomberg thanked everyone who phoned or e-mailed with messages of support.