The former Bayern Munich star has been out for more than a year and has undergone operations to cure tendinitis in both of his knees.
“I can’t wait to get back involved in it all,” he told the club’s official website.
“I can’t wait to play again for United, to be able to pull on the shirt and have an effect on games.
“Running out at Old Trafford will be a big thing for me. It will be amazing.”
