Hi,
This is something that has been bothering me a lot recently. I noticed that often, when I'm striking a note with my pinky, my entire pinky is straight, except for the last joint closest to the nails, which bends at a 90* angle. So in other words, my middle knuckle collapses and the knuckle close to the nails curls up.
This especially happens a lot with my right hand, and when I am stretching to hit notes with my pinky while holding down other notes with my other fingers.

I never noticed myself doing this until now, but I'd like to know how to fix it, because it bothers me a lot and sometimes the joint that curls up a lot becomes sore from all the pressure.

I hope this post made sense. I was wondering if anyone had any advice or thoughts on this issue.

Thank you

I don't have that exact issue, but...."pinky joint" issues dominate my playing and learning.

Not the joint you're talking about, but the one closer to the hand (the anatomic term is "proximal interphalanegeal joint," or PIP joint; BTW the one you're talking about is the "distal" one, or DIP joint) ....my pinkies bend 'outward' at those joints, and it wasn't always like that, but just started happening at some point, and it has been increasing with the years. That means that I have to keep changing how I hold the hand to get octaves etc. accurately. Whatever I learned in the past, I can't keep doing it the same way, or else I'll be playing 9th's instead of octaves.

I think that's part of why I take to Scriabin, which is full of 9th's.

It's hard for me to imagine the exact problem you're describing; I mean, I understand it, but it's hard to imagine the joint collapsing like that.
Then again I'd guess it would be hard for anyone to imagine my issue too.

I envy people whose hands just stay the same.
Because it means however you learn to play, it can keep working. I have to keep tweaking and re-tweaking the habits of the hand. It makes learning a lot harder, and even harder to come back to pieces that I played in the past.

Thanks for your reply, and for telling me the names of the joints!

I'm thinking now that maybe this problem started due to the fact that my pieces have much more octaves and stretches than they used to, and my pinky tried to adjust. I've always been told my hands were quite small, to play an octave my thumb and pinky forms a 180* angle. I can't bend the PIP joint and still reach an octave, so maybe I'm bending the DIP joint to compensate and avoid pressing other keys. I don't know...

I found a picture online of what my problem looks like. It's not a picture of my hand, but the person seems to have the same/ a similar problem:

Oh!

I think you mis-described it before.

Looks like it's the PIP joint you're talking about (as I was also), not the DIP joint.
i.e. it's not the one "closest to the nails," but the middle joint -- the next one down.

When I was younger, much younger, my fingers didn't behave as I wanted them to. I'm sure that was for two reasons, the muscles weren't developed and I was using much, too much force when playing.

If you simply place your hand on a surface (without using any downward force), I'm sure the form is fine, right? Anyway, as long as you're achieving the desired results as far as playing goes and you have no tension when you play, I wouldn't spend too much time thinking about it.

That happens to me with both of my thumbs. I can bend them at will 90° "backwards". (Some call it "hitch-hiker's thumb", and it's actually fairly common - it's a dominant trait in genetics) One of my teachers in college noticed that it often caused my thumbs to slip off black-keys and encouraged me to be more mindful of it.