Clijsters was injured in the second set of her second-round match against Canada's Stephanie Dubois Wednesday night and had to retire.
In a statement, she said she had an MRI and an X-ray on the wrist Thursday, and was told it was injured worse than was believed. She will not be able to defend her 2005 U.S. Open title and Belgium's Fed Cup final later in September.
"I am completely disillusioned," Clijsters said. "I will definitely not play any tennis next week and will most likely be out of action for the following two months."
Clijsters, 23, battled back from a career-threatening wrist injury last year. She has won more than $14 million and 23 singles titles in her career.