The talented 19-year-old, is on loan at Glasgow Rangers and manager Paul Le Guen confirms the injury problem.
Le Guen told Rangers World: “He has been troubled by this for three weeks after taking a knock on his knee and I am little bit worried by this.
“Our doctor will work in conjunction with Manchester United.
“Lee Martin has a problem with his knee, which is a bit worrying and it leaves us short of wingers.
“It is bad luck, but we must keep our head up and keep working.”