Right thumb slips off grip at top of backswing

[Remcat]

Hello,

I had some pretty serious wrist surgery done when I was a teenager due to a broken bone that didn't set properly (scaphoid if anyone is familiar). Well, now, 15 years later, I'm starting to get into the game of golf. I've noticed that on some shots, at impact, my club face twists outwards - effectively causing the ball to either go directly to the right or at best slicing the ball. I've started to correlate this to the fact that on some of my swings, my right thumb slips off the grip and my thumb ends up wrapped around the club instead of on the top of the grip lined up with my other thumb as it should be.

What I'm wondering is if there's anything I can add to the grip to keep my thumb from slipping off like that. As I tried to describe at the beginning, the reason this is happening is because it's much more comfortable for my wrist if my thumb slips off. I can't even tell i'm doing it most times until it's too late. What I was kind of thinking of was something like those pencil grips they make for young children learning to write. You slide it onto the pencil and there's a notch for each of your fingers. I'm wondering if I might be able to find (or hack together) something similar for my driver.

Thanks in advance for any advice you might have!

_Ramy

[Remcat]

in case I haven't said it already, i'm a right handed player.

[TourSpoon]

The right thumb is not really on top of the grip, but a little to the side. I am not sure what you mean by wrapped around the side, but as you can see from Hogan's grip, the thumb is not directly on top.  You should be able to swing the club without too much issue without that thumb so maybe a picture of what you are doing may help.  As far as a training grip, there are some out there for a practice club or heavy swinger, but such an aid is not legal for regular play.