The Czech sharpshooter got hurt in the ACB play-off semi-finals and Dr Antoni Dalmau, who performed the operation, said: "It's a serious injury for any sportsman because it's the strongest tendon in the body and it's vital, for example, to push off (and jump).
The injury means that the recovery process will be six months if all goes well. It's the most important injury he's faced in his career and it's not surprising that he was worried."
Barton, 29, is one of the Czechs' best players but hasn't been able to play in qualifying games in the past year due family issues.
He had been set to represent the national side this year but will now do well to recover and play by the beginning of next year.