Hickey has battled through his second season at the club with the injury, managing six games. He has also been sidelined by a corked quad and a hot spot in his foot.
He is the seventh Saint to be ruled out for the rest of 2014, joining Eli Templeton (arm), Arryn Siposs (shoulder), Tom Lee (shoulder), Daniel Markworth (hamstring), Beau Maister (shoulder) and Jimmy Webster (foot).
The young ruckman, who has struggled to jump in recent weeks, will be assessed by a specialist but surgery remains the likely option.
"You're always a little flat when you find out your year is over, (but) it gives me an opportunity to really attack the 2015 pre-season," Hickey told Saints.com.au.
"I didn't want to try to sneak two games in at the end of this year in case I jeopardised next year.
"It's been an ongoing issue for a couple of years and I've just managed it.
"This year it's just gotten worse so I could probably play on but I haven't been able to jump or run very well lately."
Hickey said he didn't feel he had met the standards he set for himself in 2014, but he had proved he could hold down the No.1 ruck role, giving him belief going into the 2015 pre-season.
