Onions had been having extensive treatment for a stress-fracture related back injury since May in the hope of being fit for the Ashes tour to Australia, which starts in November, but surgery is now his only option for recovery.
"Obviously I'm shattered to have been ruled out of the Ashes with the prospect of a lengthy recovery period," said Onions, who will have surgery on Monday.
"After experiencing the euphoria of being part of an Ashes winning England team last year I was determined to get myself fit for selection ahead of this winter's tour of Australia," he added.
Onions, who has not played for England since January, picked up the injury in practice before the two-test series against Bangladesh in March.
"While I'm devastated to be facing such a long lay-off from cricket I'm determined to overcome this setback and make sure I get back bowling again next year and work my way back into England calculations."
"It's been a difficult period for me but I realise that I have to have this operation if I want to play cricket again," Onions added.
(Reporting by Neil Maidment; Editing by Alison Wildey)
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