It was during the 16-16 draw with the Fijians that he picked up the shoulder injury and when he returned to his club a scan showed he needed surgery.
He now faces three months on the sidelines, which means he will miss the remainder of his club's Pool matches in the Heineken Cup and the opening game of the 6 Nations against England on Friday, February 4.
"George has done some serious damage to his shoulder. The original injury happened against Fiji," said Scarles coach Nigel Davies.
"He was deemed fit to play against New Zealand, which he duly did. When he returned to us our physios looked at him and we were a little bit concerned at the extent of the injury.
"He was then scanned and it became clear that it was a lot more serious than originally thought. The danger was that if it was left as it was he could have dislocated it, so we had to react to and he has been operated on to secure his shoulder."