Benson Henderson prefers to remain active.

But major knee surgery has left the former UFC champion on the sidelines since last December.

Henderson (24-7) told MMAjunkie recently that he had surgery to repair his ACL, MCL and two meniscus in his knee, all of which he had going into a December meeting with Michael Chandler for the Bellator lightweight title.

“(The injury occurred) about two months before the Andrey Koreshkov fight, actually, but I didn’t feel like it really affected my performance,” Henderson said. “I don’t make excuses. It didn’t affect any of my performances. I was able to be smart about it and train the way I wanted to for all my fights. But for the Chandler fight, it had got worse and worse and worse. Just gradually it got worse, and I wasn’t able to do certain things.”

Henderson remains hopeful for a return to action before the calendar year ends.

“My surgeon has said nine to 12 months because it wasn’t just the ACL; it was ACL, MCL and meniscus,” Henderson said. “Because it’s everything it was, he recommends a longer layoff so I can do my due diligence with the rehab and all that stuff. He says nine to 12 months, but I’m a little bit more optimistic than that with me being the fighter I am. I’m a little bit more risky, so we’ll see.”