C.J.: WCCO sport anchor Mark Rosen didn't dare test out his new knee at the State Fair

It's just a coincidence that part of the recovery for WCCO-TV's Mark Rosen's full knee replacement took place during the State Fair.

KFAN colleague Common Man has been telling listeners it was hip replacement just because passing out misinformation is more fun. "Common keeps saying 'hip' for a bit. I've been working my butt off the last four weeks to get back," Rosen told me Wednesday.

Tennis and normal wear and tear on that knee had Rosen limping noticeably. Six years ago he had a "realignment that kept the knee intact." By the time he went for surgery Aug. 10 to install a new titanium knee, he was told his knee was a 9 on a scale of 10 for a major repair.

"It was out of whack. I had a lot of bone chips in there. I'm happy I got it done. I was unhappy. It was wearing me down. I worked with some great people, getting the flexibility back and hopefully inspiring others to go through this. I've been working hard every day getting it stretched out, doing the right thing. I found out in a hurry the exercises are extremely important. I've been very diligent going to Mayo Clinic downtown and icing the heck out of it. Feels good to be back at work, too. I'm down to one crutch."

And the right crutches — Minnesota's Mobilegs: "Those things are life savers."

Rosen said he was tired of "waving at Frank and Amelia with my ice machine on my leg. … I made it back for Stephen Colbert's debut" Tuesday on "The Late Show."

But funny how Rosen avoided the State Fair.

He would have if someone in the State Fair crowd had caught that knee just right. "It was not a good place for me to be with all the ruts and people." Then I'd have had a much more interesting item about Rosie going crazy with his Mobilegs.

The State Fair needs more line dancing. There was line dancing in the street one day, but for my money the best performance was Thursday when the "Gotta Dance" line dancers (identified by fair marketing and PR woman Brienna Schuette) hit the Carousel Park "UCare Celebration" stage.

These St. Paul dancers (http://tinyurl.com/p9ovtde) should be hired to conduct official State Fair line dances hourly. Kudos for the music selections and for enticing young people from the audience on stage to join them dancing to Silento's "Watch Me (Whip/Nae Nae)."

That dance epitomizes everything I dislike about popular dance expression: It's stupid and nonsensical. But it's harmless. Even ABC is promoting the next installment of "Dancing with the Stars" by having its professional dancers Nae Nae: http://tinyurl.com/o78mxkx.

"Glad you enjoyed them!" Schuette said when I called Wednesday to make my "Gotta Dance" pitch. "Hearing you talk about it, I wish I hadn't missed it. Now I have to look up how to do the 'Watch Me Whip and Watch Me Nae Nae.' I'm so behind the times."

There was the weirdest lack of energy from Marino during this show. He seemed very unlike the way he was as an analyst for CBS' NFL show.

Minnesota's Wayne Wilderson has landed another big commercial account. He's the guy in the Bank of America "Preferred Rewards" spot at the white board who is "uncomfortable with the green marker."

C.J. can be reached at cj@startribune.com and seen on Fox 9's "Jason Show." E-mailers, please state a subject; "Hello" does not count. Attachments are not opened.