It’s not known exactly how Louis, 21, caused the injury but our guess would be that he probably over zealously jumped up and down one too many times.
The singer tweeted ahead of the band’s Belfast gig on Monday about his ailment, making light of the situation with the world’s worst pun.
He wrote: "Knee hurts... Ah well f**k it . I apologize if I'm not jumping around on stage as much, stupid knee ! #kneedtogetbetter (terrible joke) (sic)".
Well at least he acknowledged the joke wasn’t his best work.
And it seems that Louis isn’t the only person who is concerned about his injury.
The One Direction singer’s mum Joanna also took to Twitter about her son’s dodgy knee.
She wrote: "My baby first born has a poorly knee! Xxx."
Even as part of the world’s biggest boy band, it seems there is no escape from embarrassing mums.
Louis managed to get through the performance however, along with the rest of the Belfast gigs this week.
His band mate Niall Horan, 19, tweeted about his enjoyment of their time spent in his home country, as well as making reference to Louis’ knee.
With the amount of coverage this part of Louis’ body is getting, we wouldn’t be surprised if his knee got his own Twitter soon.
Niall posted:"Belfast! That was an amazing, poor aul Tommo an his knee! Hahaha! Great week up here ! See ya soon! #1DTMHT (sic)"
One Direction will be finishing up their UK and Ireland leg (or knee) of their world tour on April 19 in Manchester before heading off to Europe.
Let’s hope Louis gets better soon- he’s got a heck of a lot of jumping around on stage still to do.
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