Ahead of a crucial run of fixtures, which could be pivotal in the Gunners' quest for a top-four finish, Wenger will have to cope without several important players.
Mesut Ozil became the latest key man to be confined to the treatment room after picking up a hamstring injury in Arsenal's Champions League draw with Bayern Munich on Tuesday, joining Jack Wilshere, Theo Walcott and Aaron Ramsey on the sidelines.
And the French manager revealed he will be examining what is causing such a lengthy injury list.
"I am concerned that this happens," Wenger said, quoted in The Guardian.
"If you look at our overall injury list going into such a decisive part of the season, we have no Wilshere, Ozil, Ramsey and we went to Bayern without Gibbs and Monreal.
"It's very difficult to find an obvious reason why."
Wenger is especially concerned with Ramsey's injury problems, as the Welsh midfielder looked set to return to the squad for Sunday's north London derby with Tottenham, but will not make it.
"That's our worry at the moment, Ramsey is taking longer than expected," Wenger added.
"We have to be very cautious with him.
"When will he be back? I believe it's two more weeks now."