Kerry Katona has been diagnosed with trigger finger and has been left in agony by the condition

After seeing a doctor, Kerry, 36, was told that she had the condition trigger finger - a common disorder called Historicopous which is characterised by the catching, snapping or locking of the involved finger flexor tendon.

It is known as trigger finger because when the finger unlocks, it pops back suddenly, like if you were to release a trigger on a gun.

Revealing her diagnosis on Instagram, she said: "Just had to have an injection in my hand as I have a "trigger finger" in so much pain x (sic)"

A common treatment for trigger finger is for the sufferer to undergo a course of corticosteroid injections in the tendon sheath of the affected finger, which in patients cures the issue in a matter of weeks.

If those injections do not work then the problem is usually resolved by a relatively simple surgical procedure which involves a surgeon cutting the sheath that is restricting the tendon.

Kerry's trigger finger diagnosis comes in the same week that she has admitted to her fans that she's been struggling with her bipolar.

The blonde star - who is married to George Kay - was diagnosed with the condition in 2005 and she has always told her family, friends and five children about her battle with the mental illness.

Kerry took to Instagram to admit she was having a tough few days but she was working through it.

She said: "Feeling blue bi-polar is a bitch! Just taking that first step is a battle almost won! (sic)"