-What is the size & shape of the "knot"?
-Does it stick up [above the skin surface], or is it BELOW the skin?
Please note that your well-thought out responses to these questions will
greatly assist me in narrowing down the possible diagnoses, so I can reply to you
with more accurate and helpful medical advice.
Thanks, --Dr. Steve, Your Online Family Doctor
This is most likely a small:
Ganglion Cyst [often occurs on fingers or wrist].
See detail link:
As the link states--proper treatment is either:
Since it's impeding your wedding ring, I suggest you to see an Orthopedic surgeon--who can do the proper treatment to get rid of the cyst.
I hope you found this to be helpful-IF SO, please hit **ACCEPT** as you read this Answer. (Positive Feedbacks and Bonuses appreciated also). THANKS !
(also-you can ask a followup Q, if you need to). "CHAT" is available too.
Best Wishes for your Health,