A tall, blond man on crutches hobbled into a classroom at Centennial Sportsplex as 48 boys and girls ages 9-19 stared in awe. Pekka Rinne was making a cameo appearance at a camp run by Predators goaltending coach Mitch Korn. The big goaltender was on crutches because of a hip arthroscopy procedure more than a month ago, so he had the time to answer questions from Korn’s campers. It was his first appearance at the annual camp. “I don’t usually have this opportunity to come here,” said a smiling Rinne, who usually spends offseasons in his native Finland. Although Rinne was still on crutches, he said his rehab was “going really well.” He’s following his doctor’s orders as well as advice from goaltending friends who had similar operations, Tim Thomas (Bruins) and Niklas Backstrom (Wild). “They were super nice, sharing their experience and the way they came back and how they felt,” Rinne said of Thomas and Backstrom. “The one common thing is it’s a lot of work, and you have to treat it as the biggest thing. Every day I’m working to get better.” The Predators and Rinne have cited Thomas and Backstrom as reasons to be hopeful that the 30-year-old, two-time Vezina Trophy finalist will come back in top form. Backstrom, who had hip surgery in April 2009, returned the next season and started 58 games. His save percentage dropped from .923 to .903, however, and his goals against average spiked from 2.33 to 2.72.