Ozzy Osbourne and Sharon Osbourne's daughter revealed on Twitter that she suffered the "excruciating" injury while falling out of bed.
"I must be the most accident prone/stupid person in the world[.] I fell out my bed while sleeping last night & fractured my hand in 3 places! I'm staying in a hotel and the bed is so tall I must have dropped about 4 1/2 feet," she tweeted.
Kelly eventually had her injured hand wrapped in a cast and is now under the care of her mum Sharon.
"It's my left hand & I'm left handed so my mum has to brush my hair & cut my food 4 me I feel like a baby again. Of course my mum is loving it! The worst part is I permanently look like I'm giving everyone the thumbs up because of the way it's casted! I look like such a t**t," the Fashion Police star joked.
In November, Kelly was briefly hospitalised when she suffered a head injury.
Last week, Kelly and friend Miley Cyrus urged Twitter to remove cyber bullies after receiving a series of disturbing messages.
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Watch Kelly Osbourne perform 'One Word' below: