Caton was injured in a youth team game against Bournemouth, just as he was pushing for a place in the first team, having played a small number of games for the first team last season.
Youth team coach Ian Woan said: "It was devasting news for the kid, Andy had really looked sharp this year, and both Iffy and myself only felt it was only a matter of time before he would break into the first team set up again and stay there."