"Had surgery on my wrist yesterday & all went well...even though I'll be setting off airport metal detectors from now on."
"I'm so thankful for the doctors, nurses, family & friends who've been taking such great care of me," she added.
Underwood's rep had confirmed Saturday to The Tennessean that the star broke her wrist and suffered cuts and abrasions when she fell on the steps outside her house Friday.
The singer was treated at a nearby hospital and released.
"Thanks so much for all the well wishes everybody...I'll be alright...might just take some time...glad Ive got the best hubby in the world to take care of me," Underwood tweeted Sunday, referencing husband Mike Fisher.
Underwood and Fisher, a retired NHL star who played for the Nashville Predators, married in 2010.
The couple share 2-year-old son Isaiah, and enjoyed a superhero-themed pajama party with the toddler over the summer.
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