The American Idol host underwent a "procedure" after filming the show on Wednesday as he needed treatment to remove scar tissue from an old tendon injury.
He revealed on Twitter: "I have a tiny tear in my elbow...pausing life for procedure."
He later explained during his KIIS-FM show: "I had a probe stuck into my right elbow. I'm not a robot [but] they went in with a tiny little probe and they scraped some scar tissue from the tendon, cause I tore the tendon from working out."
Ryan - who admits he is "not a great patient" - was wide awake during the surgery but admits he couldn't bear to watch what the doctor was doing.
He said: "I couldn't look. But I could feel the pressure.
"It was very easy and practically noninvasive."
While the procedure went well, Ryan hadn't expected it to take so long and ended up with a schedule clash.
He said: "I didn't calculate suturing into my schedule. I thought it was an in-and-out, 12-minute procedure."
The 37-year-old star later tweeted a picture of his arm showing where he had been treated.
Alongside the image, he wrote: "Will this be noticeable in my mesh falcons jersey? funny bone not so funny today.(sic)"
24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.
Royal watchers are scrutinising the duchess of Cambridge on her New Zealand tour after husband Prince William appeared to hint a second baby is on the way. Read More »
Police have described the death of wild-child Peaches Geldof, who was found dead in her UK home, as "unexplained and sudden". Read More »
20 new pics of Kate and William.
6 best pics from the royal tour!
Check out these pics of Prince George!
10 pics from Will and Kate's visit.
Kate and Will wows the crowd!
Will and Kate hanging out with Peter Jackson.
10 photos of adorable Prince George!
The royals arriving in New Zealand!
South AfricaCity PressMarket Related
South AfricaCommunicate Cape Town ITR24000 - R27000
HousesR 2 100 000
HousesR 1 495 000
FarmsR 2 750 000