Greening has revealed that for the last two months of the season he struggled with the problem which although caused him discomfort at off the pitch failed to stop the midfielder from leading
"I felt it over the last 12 to 15 games, not so much during the games but afterwards at home," the former Manchester United man said.
"It was hard getting up off the sofa, getting out of bed and out of the car.
"I really started feeling it during the last four or five games.
"But even when it was really painful I decided to continue because the adrenalin kicks in.
"I could have pulled out of a few training sessions but you don't want to when you're at the stage of the season that you're going for promotion.
"I probably should have had a few days off from training but I wanted to get promoted so badly.
"To be fair, I don't think I told the physio until there was around three games to go because I didn't want the gaffer to know.
"If he knew I had a hernia he might think I was struggling and bring me off in games.
"I don't think the gaffer found out until the end of the season so it was mine and the physio's little secret.
"It was quite a well guarded secret!"
Despite the injury Greening was the only Baggies player to start every 46 Championship games during the promotion winning season and insisted playing through the pain barrier was well worth the discomfort as he celebrated lifting the trophy.
"I just didn't want anyone to know because I was enjoying being captain and the run we were on when we were beating Wolves and teams like that," added Greening.
"I just wanted to carry on playing and I didn't want to give the gaffer any excuse to drop me.
"I felt a responsibility as captain.
"After we clinched promotion against
"Now I can look back and say I played in every 46 games in the season and when I retire I can say what a great season it was.
"It was worth every second of the pain - and there's no pain when you're celebrating on
Jonno's appointment with the operating table on Thursday should mean a return well in advance of pre-season training after revealing the operation had been a success.
"The operation has gone fine but I didn't want to get it done until I got promoted," he said.
"I got it done on Thursday and it's a bit painful at the moment.
"I feel as if I'm walking a bit like John Wayne and I didn't think it would be this bad!
"I'm not allowed to do anything for about a week and then I'll just gradually build up to the bike and then jogging machine.
"Hopefully I'll be back flying for pre-season."