Munster flew back to Melbourne on Friday to see a hand specialist late in the afternoon, with the Storm confirming he will miss between two and three weeks.
It came after he fought through the pain of a compound fracture in the Storm's 16-12 win over Parramatta on Thursday night, returning for the second half following two pain-killing injections.
His herculean effort included a nifty dummy followed by a step and pass to set up the crucial match-levelling try late in the game, with two of his fingers bandaged in the shape of sausages.
Hurt when he made a tackle on Clint Gutherson in the 27th minute, Munster immediately left the field but returned less than half-an-hour later after treatment.
"I was a bit surprised when I saw it come out. I have never seen a bone come out before," Munster said.
"I felt my finger numb when I got out of that tackle against Gutho and I thought, 'That doesn't feel right'.
"I looked down and there was a bit of bone sticking out. Shock hit and I didn't really have much emotion.
"I got off and the doc said, 'I have to put a needle in to numb it up'. I'd much rather let it sit there. I hate needles."
Despite the injury, Munster said he did not have any significant trouble gripping the ball during the tight second half and golden-point finish.
"I bumped it a couple of times. A couple of times I got in a tackle and it was a bit wincy," he said.
"But the numbing needles helped with the pain.
"I just tried passing a little bit more. I probably didn't run the ball as much as I would like to."
Munster's surgery comes at a horrible time for the Storm, with their injury count now standing at 12.
They are already without superstar fullback Ryan Papenhuyzen for at least the first six rounds as he battles to recover from last year's fractured knee cap.
Justin Olam, Tui Kamikamica, George Jennings and Tariq Sims were among other big-name absentees for the opening round, before Xavier Coates also suffered an injury in the win.
He too will miss next week's clash with Canterbury after suffering a sprain to his sternoclavicular joint, and is in a race against the clock to face Gold Coast in round three.
Grant Anderson looms as the man most likely to replace Coates on the wing, while Tyran Wishart is expected to start at five-eighth in place of Munster.
