Sorry to read about this injury Greg....looks nasty....but should heal well by the looks.
Just one thing though....that grinder doesn't look like it has a proper 'Safety trigger' to start it. Just a dumb switch that you press and go. I can tell you that a Makita battery grinder has a switch so well designed that you almost need to be a Rocket Scientist to make it work.
Get rid of that tool, or at least, have it looked at by a pro before thinking about using it again.
Take it easy for a while, and don't blow out the stitches trying to do any hard work.
Chicks (most of them) dig scares too
I'll bet most of us have slipped when cleaning stuff with a bench mounted wire wheel. I have several times but that is because I like to clean the threads of every bolt that I install and I like using OEM factory hardware. My fingers and hands are scarred up from cuts, scrapes, abrasions and such. I will leave this earth looking like a man who lived and had fun doing it.
People in a rush are the ones that usually get hurt, something stupid...
I didn't get too many cuts or injuries working my trade
awning installer w/sharp aluminum panels, for my fathers co.
Add On Home Improvements in HS 1st
or an attendent at a Shell Service station, in Georgetown while in HS, $1.65 an hr
filling mostly logging trucks with diesel & washing off mud & cleaning windows
could have fallen tones of times, but didn't
or doing tires on split rims,
I was oblivious to how dangerous it really was, never got hurt
I went thru apprenticeships as Carpenter
(with a termite co., really cool dude raced Fuel F/Cs),
as a Plumber/Pipefitter Union
(my stepdad was a union pipefitter wanted me to be one, no thanks)
Electrical (IBEW for PG&E powerplants, operator) misc. equipment operator, welder etc.
The 1st 2 co.s I started early on, was Framing & Plumbing, both C license/s
skills I learned for both my dad's
PG&E for a 2 year stint in the powerplants as a combination welder,
machinist helper, operator, then a foreman of shutdown crews shifts work/crap...
Then back to the trades,
I got tired of the layoff, I started my own companies
& then in Dealership Facility Mngmt, huge group, of commercial properties,
with everything under the sun, from front driveway to the back fence I/we did it all...
never cut myself, with a hand power tool
never cut myself, on or with a saw, Table, Skill/worm circular/or beam, or reciprocating/Sawzall
had few close calls on ladders
& walking top-plates, or rolling joists/rafters etc., I was always, 'the high man'
My worst injury on the job, in decades of work, was a cut from a utility knife,
installing sheetrock
& I was thinking as I did it too,
"
I shouldn't be pulling it towards myself"
& low & behold, I cut the palm of my left hand, with the knife edge
when it slipped...
While finish cutting out electrical box holes...

Went to Kaiser ER, & I think it was like 6 or 8 stitches,
back at work the same day...
Installing sheetrock still...
got quite a few flashes welding, stainless tube in boilers, at PG&E
10 welders going in the boiler, you couldn't hardly avoid it
had a few smashed thumbs as a carpenter, part of the trade
poked myself with every sharp object you can think off, none bad
I had a couple close calls with extension ladders etc.
I'm not sure if I was just lucky or I paid attention when using the tools of the trades,
that I knew I could get hurt with, saws or 1/2 chuck augers/right angle drills etc.
(them things can kick back like crazy), power hammers, compactors, jack hammers etc.
Especially fabricating & building racecars, seems everything tries to kill ya'
get well quick
It looks like they (nurse or dr.) skimped on the # of stiches per inch
that'll leave a nice scare...