French striker Thierry Henry may not be fit to play with Arsenal at the start of next season due to an Achilles injury he's currently playing with, Arsenal doctor said. Professor Nicola Maffulli who has been working on Henry's injury at Arsenal said the Frenchman who is playing with his country in the World Cup needed to take some rest during summer. "The problem for Henry was not an inflammation of his Achilles, but the fact that it wasn't repairing itself sufficiently between matches," Maffulli told News of the World on Sunday. "What Thierry needed was a summer of rest, but of course he's placing the tendon under further stress." After a slow start at the World Cup, Henry leads France to the competition's semi-finals, scoring three goals so far including the winner against Brazil. However, Maffulli said that Henry's participation for further games with France can ruin all the work he did to heal the striker's injury pains. "Arsenal originally came to me because they were having problems with Thierry's injury and I was able to come up with a range of methods that allowed him to return to his best form last season," Maffulli said. "But him playing in the World Cup could affect his pre-season preparations and ultimately his ability to get ready for the start of next season."