@edward2000 – Have you had yourself checked for Heamachromatosis – arthritic finger joints are one of the symptoms.
It’s genetically inherited condition where the body doesn’t regulate iron levels and over many years it increases and eventually causes issues in organs and joints. Caught early it’s not a biggie but left untreated can cause major issues in later life. I found I had it a few years back, it’s now under control via simple blood donations (the body depletes its iron stores to make new blood). I found out because my sister had it so I got tested. At the time (aged 44) I had no symptoms at all – except for some mild arthritis type symptoms in my hand that I’d just put down to ageing.
The easiest test is a blood test, looking for level of iron – referred to as “SeFn”. Any doctor could arrange that, or even home test kids should give a rough idea.
NHS info page link