Mystery - Thumb went black

[AnonKat]

So yesterday I noticed my thumb was bruised and swollen. But there is no paina and is moving normally.

I didn't bang it or damage it at all! Any ideas please?

Achenbach syndrome?

https://www.pcds.org.uk/clinical-guidance/achenbach-syndrome

I had this happen two or three times several years ago, I have no idea why as it hasn't happened since.

I was going to say achenbach syndrome too. It’s happened to me a few times, I get a sudden sharp pain like someone has flicked my finger with an elastic band then a bruise appears. This was my last one.

I get this too but didn’t know there was a name for it.

Thank you! The human body is fascinating sometimes! I had zero pain at all.