"He does a lot of dancing on the stage and he does a lot of stuff with his mike stand. He put his stand down and twirled around and stepped backwards off the stage," Sanborn said.
Halfway through the performance, Tyler fell onto a couple of fans in the middle of what was a record crowd, Sanborn said. Security rushed to help him and the crowd cheered when Tyler got back up.
"He was good natured about it," Sanborn said. "He was in good spirits when he got in the helicopter. He was talking and joking with the physician."
"It was an unfortunate end to an extraordinary evening," he said.
Tyler suffered minor head and neck injuries and a shoulder injury, but it wasn't immediately clear how serious that was, Sanborn said.
After he fell, which was halfway through the performance, Tyler was eventually taken backstage, Sanborn said. Around 12:15 a.m., Aerosmith guitarist Joe Perry came out to tell the audience Tyler was being taken to the hospital and that the show would not go on.
A physician at the concert venue attended to Tyler and the frontman was flown to Rapid City Regional Hospital, the only major hospital in the region, Sanborn said.
Jennifer Horton, the hospital's vice president of public relations and marketing, said early Thursday that Tyler wasn't in the hospital directory. Under the privacy laws, that means the person is either not there or chose not to be included in the directory, according to the hospital's Web site.
Tyler attended Sturgis last year to promote his Dirico Motorcycles line and was back this year to do that again and play at the Buffalo Chip.
Fans were disappointed the concert was cut short but hoped Tyler wasn't seriously hurt.
Lance Yellow Robe, who said he was 8 eight feet from the stage when Tyler fell off, told the Rapid City Journal "you could kind of see it coming because he was dancing all over the stage.
"I hope he's OK," Yellow Robe said. "I could care less about the concert being canceled."
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