"Theo had a dislocated shoulder and he had surgery today. He will be out three months," confirmed Wenger.
"But there is no [long-term] concern about that. Once the surgery is done and it is solid, there is no concern at all for the future of Theo Walcott. Not at all."
Wenger also remarked: "Theo is in fact out three months to play, but it is not [necessarily] the first game where he comes back. That is difficult to rate because we have had experience of a player coming back from such an injury.
"It can take time to use his shoulder again and every little protection of the ball, you need your shoulder. At the start they use their body and don't use their shoulder as much as they should. It takes some time to get used to that.
"The experience we had with Theo was that [the last time he injured his shoulder] he played after three months. He was not completely competitive after three months. He could play in the games."