Newton said his doctor ''downplayed'' the length of time it would take for him to recover. Team physician Robert Anderson performed the surgery on March 19.
''Something I thought where I would have a cast on for a couple of weeks ended up being a couple of months - and then the rehab started,'' Newton said in his weekly press conference Wednesday.
The ankle injury, along with the broken ribs he suffered in the preseason, has limited Newton's running ability. He has just eight carries for 33 yards and no touchdowns in three starts, well below his normal production.
The former No. 1 overall pick ran for 2,032 yards and 28 TDs in his first three seasons in Carolina.
Newton said he was under the impression the surgery was minor ''to clean up ligaments and whatnot.''
The two-time Pro Bowler said he was surprised when he began reading media reports that he would be out longer than he initially anticipated.
The Panthers announced in a press release March 19 that Newton would miss four months.
''That's when I started scratching my head like, man, this may be bigger than I thought,'' Newton said. ''I'm still in that mode where I'm realizing that I'm trying to recover from a major ankle surgery where it was displayed to me originally as a little cleanup.''
Panthers trainer Ryan Vermillion responded to Newton's remarks on Wednesday in an email, saying ''at no time was Cam's surgery categorized as a simple surgery.
''From the beginning his timeline for return to practice was four to six months,'' Vermillion said. '' ... Like many orthopedic surgical procedures you continue to improve as you participate in your sport. That is exactly what Cam is doing, improving weekly. He has had some setbacks from other injuries but his ankle continues to improve and get better.''
Newton's isn't angry at the team or their medical staff.
In fact, he went on to say that he doesn't question the decision to have the surgery.
''Hindsight is 20-20,'' Newton said. ''I'm not going to be up here (behind a podium) thinking about, if this would have happened or that would have happened. Whatever decision that was made I'm behind it 110 percent.''
The ankle has been a nagging problem for Newton for years, but it became more bothersome when he injured it in Carolina's NFC divisional playoff loss to San Francisco in January.
The team waited more than a month to see if the pain subsided. When it didn't, the decision was made to have surgery.
Panthers coach Ron Rivera said Wednesday he believes it was the right decision.
Rivera said when Newton fractured his ribs in an Aug. 22 preseason game against New England it set his recovery from ankle surgery back.
Newton missed a week of practice and the team's season opener at Tampa Bay.
The ribs ''made it difficult for him to do the rehab that he needed to,'' Rivera said. ''Part of the whole rehab plan was to always have him on the field when we got to training camp. You can't make up for the type of twisting and turning he will do as a quarterback in the training room. Having him on the field and having him miss those 10 days I think kind of slowed him down as well. Those are 10 days that he really could have used.''
Newton downplayed his lack of running attempts, saying the opportunity to run hasn't presented itself as much this season.
But it is clear Newton doesn't have the same elusiveness in the pocket he had the past three seasons. Panthers offensive coordinator Mike Shula has not called many designed running plays for Newton in an effort to protect him from further injury.
Tight end Greg Olsen said he doesn't doubt Newton's toughness, calling it one of his greatest qualities. He said that while Newton may not be much of a factor as a runner, he's used the time to develop into a better passer.
''He's throwing the ball as good, if not better, than he's ever thrown the ball,'' Olsen said. ''And that's saying a lot.''
Newton hopes he'll be a bigger part of the running game in the weeks to come.
''Hopefully I will be able to display my running talents soon,'' Newton said.
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