Vunipola learned on Sunday he will be out for four months after injuring a knee during Sarries' defeat of Sale.
The 24-year-old had only recently returned after a year blighted by knee and shoulder problems, the latter forcing him out of the Lions tour.
Speaking prior to his latest setback, he said "something has to change".
"I didn't enjoy being on the surgery table twice in one year and that's supposed to be deemed as normal," he told BBC Radio 5 live's Rugby Union Weekly podcast.
