The midfielder had to be substituted during the 2-0 Champions League win over Borussia Dortmund on Wednesday after picking up a suspected calf strain.
We have been unlucky with injuries. What can you do about it?
The Gunners boss also said that goalkeeper Wojciech Szczesny has not been training, while Yaya Sanogo has been struggling with a hamstring problem.
“We have so many knocks, I can only sort it out this morning,” said Wenger on Friday. “Szczesny has not practiced, Arteta is out, Sanogo has problems.
“We have been unlucky with injuries. What can you do about it? Not a lot.”
The Frenchman also said that Theo Walcott is out with a groin injury. “He has a groin problem that he came back from England with. He’s not available,” he added.
Asked about striker Danny Welbeck’s fitness, he added: “He had a swollen knee so he wasn’t available for Dortmund.”
Wenger, however, said that Laurent Koscielny is fit and ready to start, while Mathieu Debuchy is around two weeks away from a comeback.
Wenger was also quizzed about Jack Wilshere after the midfielder was ruled out of action for around three months following ankle surgery on Thursday.
“We knew he would have surgery,” said Wenger. “He’s focused to come back and finish the season well.
“His injury is a consequence of a very bad tackle that was not malicious. He deals very well with tackles and kicks but nobody would’ve dealt with that tackle.
“He loves the game but he has also learnt to deal with adversity at a young age. He’s determined. If he has no problems with his joints he will make a massive career.”
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