The 44-year-old allegedly suffered the break while walking her dog, meaning her leg is now in a cast.
Because of this, Kat and Alfie Moon’s dramatic festive scenes are having to be shot from the waist up.
To minimalise the risk of ‘missing scenes’, EastEnders has drafted in a body double for unavoidable body shots.
But Jessie has been praised for her professionalism and show sources insist Kat and Alfie’s storyline will not be affected.
An insider told the Mirror: “Luckily it has meant that none of the story has been changed at all – you just won’t see Kat doing laps around Albert Square.”
And a spokesperson for the BBC One soap added: “Jessie, like a true professional, has managed to film everything.”
Viewers saw Kat and Alfie [Shane Richie] set off for a new life in Spain earlier this year, after winning big on the Lottery.
It is thought Kat will finally discover the identity of her secret son in December – and many suspect it could be Sean Slater…
Next year Kat and Alfie will travel to Ireland for a six-part EastEnders special.
Are you looking forward to having them back for Christmas? Let us know on Facebook and Twitter.
Read More: Everything you need to know about the EastEnders characters