Wenger said Lacazette was troubled for weeks by the injury before he was sidelined.
"I think we are (ready to see the best of Lacazette) because I realise now that he was not himself for a while," Wenger told reporters on Wednesday. "That explains why his goals dried out...
"It was not traumatic, he was a good player but I think in the last seven, eight games he played he was not completely free with his knee. Unfortunately in our job you need your body and that's why when you are not 100 percent you cannot play well."
Lacazette could start in Arsenal's Europa League quarter-final first leg against CSKA Moscow later on Thursday as the north London club push for their only chance of winning a trophy this season.
Arsenal, who are sixth in the Premier League, host Southampton on Sunday.
(Reporting by Aditi Prakash in Bengaluru; Editing by Peter Rutherford)
