The problem came to light after the 22-year-old sustained a stomach injury in training a month ago, and he now looks set to be out of action until around Christmas. Manager Arsene Wenger told the club's official website: "He has a hernia and had surgery on Thursday. He looks like he will be out for between four and five weeks. "At first he had an abdominal strain, certainly caused by the fact that he had a hernia already. When the strain was healed we discovered that he had a hernia. We had a fear that could be behind it so we decided to do the surgery." Gibbs' absence was not the only defensive blow for Wenger ahead of Saturday's Premier League game at Norwich, with Carl Jenkinson suffering from a back problem. "We have had some bad news because we have lost two full-backs over the break but apart from that all the players came back in good shape and everybody is available," Wenger said. "Carl has a stress fracture in his back. That's just about rest now. We discovered that because he had a pain in his back. First you monitor it, then play a little bit and then you check again because you are cautious. "We found a small stress fracture that we noticed at an early stage. If he continued to play it could have got worse and then he could be out for a long time. So at the moment the specialist has decided to rest him." He added: "[Abou Diaby and Marouane Chamakh] are both back in full training again. Diaby has been out for four or five months so he will need some adaptation. Chamakh is available for the weekend." Wenger, meanwhile, hopes the presence of club legend Thierry Henry at training this week can help inspire his team as they look to maintain their resurgence. The 34-year-old former Gunners captain has used the opportunity to rejoin his old club after the New York Red Bulls' Major League Soccer play-off campaign came to an end. With Arsenal looking to make it five league wins in a row in Saturday's lunchtime kick-off, Wenger believes the return of Henry - who left for Barcelona in the summer of 2007 - will be positive all round. Speaking to Arsenal Player, Wenger said: "Thierry was in with our training [yesterday], and he does not need to show how good he is. "He just wants to stay fit and enjoy the football club again, because he is at home here and it is always good to have him back. "When you are not the day before the game, it is possible of course for him to practise with the first team. "It is always a lift to see what a big player he still is."
