The former Rangers and Scotland striker, now a popular football pundit, shared his experience on talkSPORT.
McCoist revealed that the condition runs in his family and despite having had two operations on it, the issue has returned.
Dupuytren's, also known as Viking Hand, causes fingers to bend inward due to thickened tissue, runs in his family — with both his parents also suffering from the condition.
"I've got Dupuytren's. It's a hereditary thing where your fingers close in" McCoist explained.
Speaking about the operations, he explained: "I have had them done twice. I went to see the doctor and he said to me 'Did your grandfather have it?' I said 'I don't know' because I never met any of my grandfathers, sadly they passed before I was born.
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"My wee mum had it as well. My mum had it, my dad had it, it's a hereditary thing.
He continued: "The bizarre thing with Dupuytren's is when I went to see the doctor he said 'I will operate on it but it will come back in roughly nine years'. And I swear to God nine years later it came back.
"I have seen myself sending a text message which takes me five minutes to text with one finger when I should just dial the number."
Around two million people in the UK are estimated to have Dupuytren's contracture, which worsens with age and is yet to have a definitive cure.
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Dupuytren's disease, or contracture as it's also known, primarily affects the ring and little fingers, often in both hands, and gradually worsens over months or years.
It's usually painless, but it can restrict hand movement, starting with lumps or ridges on the palm and eventually causing fingers to bend permanently.
Treatment options include surgery to remove affected tissue or skin and a needle procedure to release the tightened tissue.
McCoist is a beloved figure in football, providing commentary and analysis for talkSPORT, ITV, and Sky Sports.
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