The 22-year-old England international is set to see a specialist after damaging his ankle ligaments following a sliding challenge by Manchester United defender Paddy McNair on Saturday.
The incident came as Wilshere was driving forwards towards the United box looking to get the Gunners firing again following a first half in which they dominated but could not score, Wilshere guilty of missing a one-on-one against goalkeeper David De Gea.
Wenger believes it is his dynamic style which makes Wilshere more susceptible to such impact injuries.
"It does not look good, but the tackle caught him from the side just when he had moved the ball a bit forwards too much then, when he dived to make the pass, McNair came in to make the tackle and took him from the back and the side
When you see the picture, it is very bad," said Wenger, who described the challenge as a "bad foul" of a "young player", but one not with the "desire to hurt."
"There is no bone damage, we knew that straight away after the game, but there is ligament damage.
"It is just the extension of how much it is, which we should know Tuesday or Wednesday (of next week).
"I hope it will not be surgery, just in a (protective) boot, but it will be a few weeks."
Wenger added: "It is so sad because he just came back (from injury).
"You see in the big games he has the personality.
"It is more about his game, it shows you he is not scared to play and is ready to want to get the ball always.
"It is because he doesn't want to lose the ball, he is ready to put his body in.
"You cannot take that out, otherwise he will not be Jack Wilshere anymore."
Arsenal may have endured their worst start for some 30 years and faced plenty of negative headlines - including those generated from comments by major shareholder Alisher Usmanov - but Wenger will take it all in his stride as he prepares the team for Wednesday night's Champions League encounter with Borussia Dortmund, needing a point to qualify for the last 16.
"Do you really think you can do 30 years in my job and not take criticism? If I couldn't take criticism, I would not still be any more," said the Arsenal boss, now the longest serving manager in the Premier League.
"Do you like that everybody says that you are stupid? But that is part of it, you learn to cope with it, you believe in what you think is right.
"(Is the criticism) fair or unfair? I don't know any more what is fair, but I know what happens after you lose a big game.
"You learn to adapt, you take a distance with what is right
You know part of the game is that
I am just frustrated and sad that people who love this club do not get the results they deserve and want.
"The players put so much energy in and don't get rewarded
That is my biggest concern, the criticism? That is part of it."
Wenger continues to have complete faith in his squad's ability to come good.
"There is life in our team, there is a dynamic in our team, there is quality in our team," he said.
"We know where we failed on Saturday, I am long enough in the game to know if there is something there or not and there is a lot there, and it is part of our game, when you lose a big game you get hammered.
"I am very positive about this team, this is one of the best teams I have had for a long time."
Wenger maintains the bigger picture must be considered, rather than just Arsenal's results alone.
"We are a team who gives very few chances away, we are the team who creates most chances in the Premier League, so there are a lot of positives, but at the end of the day you either win or lose the game, yet it depends on very little things sometimes," he said.
"I believe we have a good team dynamic and what isn't working at the moment, we can get it right."
Source : PA
Source: PA