Lennon fears 10-week absence for Celtic skipper Brown
The midfielder has been in and out of the Hoops line-up this season because of the ongoing complaint but after may now require surgery after succumbing to the problem in the second half of Tuesday night's 2-1 Champions League loss to Benfica.
"Scott Brown has run his course, we may have to book him in for surgery," said Lennon.
"We are looking at eight to 10 weeks.
"He has been pushing himself to the limit and we can't keep asking him to put himself through the amount of distress that obviously he was doing towards the end of his time on the pitch.
"He has been a huge player for us this season, I think it is time to get the problem addressed and hopefully he will have something to look forward to in the new year."