"There's never a good time to get injured but this problem came at a bad time for me because I was in the squad and showing people I could score goals," he said.
"But I've had problems with my knees for a while and it was painful to get through some games.
"In the end I had no option but to have the operation, even though I knew it would rule me out for four months.
"Although I've scored some goals this season I've also been through a lot of injury problems.
"I just want to be back out there with the lads and I'm hoping I can return for pre-season."