The Celtic winger missed his side's dramatic 4-3 win over Aberdeen with the ongoing problem and Bhoys manager Neil Lennon confirmed it would keep him out of the international double-header.
"He is going to see a specialist on Tuesday, he may need an injection in his back which might keep him out for another couple of weeks," Lennon said.
"He is a huge loss. I think he is a class player and he has shown that but it has been stop-start for him.
"He will be out of the Scotland squad.
"It is a concern for him, I don't think he is fully developed yet. Once he fully matures physically, you are hoping these things settle down.
"He is just a little bit unfortunate at the minute.
"Hopefully it won't require surgery, it may just need some more manipulation in some areas."
There was better news for Celtic keeper Fraser Forster, who should be able to join up with the England squad, despite picking up a knock.
Lennon added: "He was feeling his groin after the game but he should be OK to go away with England."