Sculthorpe was appointed Great Britain skipper in May 2005

The 29-year-old, who has just returned after six months out following major knee surgery, is having an arthroscopy to flush out floating debris.

"This is a result of general wear and tear over 300-plus matches," said a St Helens statement.

"It is not an uncommon procedure for players who have played so many games."

Sculthorpe had a knee operation in early October but returned a fortnight earlier than expected in the World Club Challenge win over Brisbane last Friday.

He had a fairytale comeback, scoring a try and kicking three goals as Saints sealed a 18-14 victory.

Sculthorpe is expected to be back in action in time for the home game against Hull KR on 23 March.

"It is obviously frustrating for both Scully and the club," said Saints coach Daniel Anderson.

"We want him to play and he wants to play but the fact is that injuries are part and parcel of the game.

"It is important to keep this in perspective, however, and remember that this is a routine operation."