Britney Spears has shared a video of the moment she broke her foot while dancing ''full throttle''.

The 38-year-old singer posted a clip to Instagram of her showing off her moves while Kings of Leon's 'Sex on Fire' played in the background and the video ended with the loud sound of her bones snapping.

She captioned the video: ''I haven't danced in six months so I was full throttle at this spot.

''And yes .... I know I'm barefoot .... don't laugh but I grip the floor better that way !!!!''

''PS you can hear where I broke my foot here. Sorry it's kind of loud !!!!! (sic)''

Britney had addressed her injury for the first time earlier in the day when she read out letters from fans and apologised for not having made it to Los Angeles' immersive fan experience 'The Zone'.

Showing off her cast, she said in the video clip: ''I'm so sorry guys I couldn't make it to the zone but unfortunately, I've been dancing and I broke my foot.''

Britney's boyfriend, Sam Asghari, revealed last week she'd suffered the painful injury when he shared an Instagram post featuring her cast, on which he wrote the word 'Stronger' in green and blue pens, referencing her 2000 hit single.

He captioned the post: ''When you break something it tends to heal stronger specially when you're my Girl. My lioness broke her metatarsal bone on her foot doing what she loves which is dancing.

''Wishing her the best recovery so she can jump, run, and dance her butt off #stronger.''

Britney's sister, Jamie-Lynn Spears - whose 11-year-old daughter Maddie injured her arm at school earlier this month - joked about the family's medical issue in the comments of Sam's post.

She quipped: ''Between her and Maddie we are running a hospital!!''