Adebayor suffered the injury in Saturday’s defeat to Stoke.
Adebayor will miss the clash with Manchester United on Saturday and winger Theor Walcott could also miss the game.
Walcott suffered a should injury during the defeat to Stoke.
Wenger said: “Adebayor will be three weeks.
“Walcott could be days or weeks. It is the shoulder he had the surgery on.
“We don’t know about Gallas yet but Sagna will be back in the squad.”