The club's assistant manager Mark Bowen has claimed that there is no specific timescale on Cameron's recovery, but reports have claimed that the USA international is likely to be out for another fortnight.
"It's been troubling him for a while, so the time has come for an operation," The Sentinel quotes Bowen as saying. "He started feeling it last season, then obviously went to the World Cup and came back to us still feeling a bit sore.
"These things tend to manifest themselves over a period of months and now the time has come, but it's difficult to say how long we will lose him for."
Cameron has featured just once for the Potters this season, in the team's 3-0 win over Portsmouth in the Capital One Cup last month.