Spice Girl Melanie Brown has suffered an unexplained injury in New York that required surgery to prevent her from losing her hand.

Brown said online Monday she needed three hours of surgery to repair damage to her hand. She also said she suffered two broken ribs.

She posted a photograph on Instagram and thanked doctors and nurses for their "wonderful" work but did not explain how the accident occurred.

Brown cancelled a book signing event in New York and apologized to fans who had bought tickets.

The Spice Girls are planning a reunion tour without the services of Victoria Beckham.