Underwood previously stated that she had broken her wrist in a fall, but she explained in a recent post to her fan club members that her face actually bore most of the brunt.
"There is also another part of the story that I haven’t been ready to talk about since I have still been living it and there has been much uncertainty as to how things will end up," she wrote. "It's crazy how a freak random accident can change your life."
"In addition to breaking my wrist, I somehow managed to injure my face as well. I'll spare you the gruesome details, but when I came out of surgery the night of my fall, the doctor told [Underwood's husband] Mike that he had put between 40 and 50 stitches in."
Underwood wrote that while she is recovering, she is "not quite looking the same."
"I honestly don't know how things are going to end up but I do know this: I am grateful," she wrote. "I am grateful that it wasn’t much, much worse. And I am grateful for the people in my life that have been there every step of the way."
"I am determined to make 2018 amazing and I want to share things with you along the way,” she ended the post. "And when I am ready to get in front of a camera, I want you all to understand why I might look a bit different."