In the "Currently" post on her website and app – which gives fans an insight into her latest thoughts, likes and dislikes – the reality star wrote that she is wearing a back brace because of the injury.
While she didn't specify how it happened, Kardashian West did add the classic Kimoji of herself crying alongside the news.
That being said, she's not giving up on her post-maternity uniform of a black spandex leotard under a fur coat just yet: On Saturday, the mom of two was spotted wearing the classic combo while hitting up Toys R Us in Woodland Hills, California, with her daughter North, 2 – though she wore sneakers, a rare occurrence for her.
VIDEO: Kim Kardashian Taught J.Lo How to Selfie!
Earlier that day, the Keeping Up with the Kardashians star also dropped off her husband Kanye West at the airport in Los Angeles.
Despite her injury, Kardashian West looked back on happier times Sunday, posting a completely nude mirror selfie that PEOPLE has confirmed is a throwback, not a glimpse at her post-baby bod.