The 22 year-old, who joined Norwich in 2014, has not featured since November because of a pelvic problem.
"It's devastating news for him and us and he will be going for surgery," Neil told BBC Radio Norfolk.
"We are trying to promote our best youth academy players and this will certainly set him back," he added.
Norwich are already short of cover at left-back after Martin Olsson joined Swansea City, while Ajax target Mitchell Dijks has turned down a move to Carrow Road.
Now Neil accepts that he may need to find cover in midfield too, with Youssouf Mulumbu and Graham Dorrans still on the sidelines.
"We might need to plug a gap but certainly the first preference is to sign someone who will make us better," he said.
"Youssuf is coming back in two weeks with Dorrans six weeks after that."
Norwich, who are 10th in the Championship, are at home to Birmingham City on Saturday.
Norwich City manager Alex Neil has confirmed that midfielder Louis Thompson will miss the rest of the season with an Achilles injury.