Charles said
Hi, Kevin,

Welcome back. I feel for you on the heart stuff. Mine hasn't attacked me yet that I know of, but I've been having signs one is impending.  Doctor started me on nitro last week because of some shortness of breath and tightness in the upper chest, and the bad news is, it seems to be helping...

 

If the limited feeling you mentioned in the third and fourth finger is only the sense of touch, you can ignore everything I say below. That sense is nice to have when playing the left hand, but not essential, especially if it's just dimmed, not gone.

If what's missing is your proprioceptive sense (your ability to tell where the parts of your finger are just by how they feel), though, that's going to play hell with your fingering/intonation.

For that problem (if it exists) I have a couple of oddball suggestions:

First one is to use tapes, and let your eyes help position your fingers.  Normally, that would be the exact opposite of what I'd advise somebody to do, specifically because you want to train yourself to use your proprioceptive sense to get your fingers where they need to go without your eyes, so you can put your eyes on things like sheet music.  But if you don't HAVE that sense, then you have to change the rules.

It would mean you'd have learn things either by ear or by learning a little bit of the sheet music at a time and playing it from memory, but you'd be able to play reasonably in tune.

 

The second oddball suggestion for handling the problem is more extreme - switch to playing a left-handed violin.  The weakness you mentioned might be an issue, but you could test it with your existing violin (you'd probably have to take the shoulder rest off, if it has one - I don't think you can just turn them around). Expect it to be rather awkward.  (Update: Being the sort to somewhat believe in putting my money where my mouth is, I tried it. Make that horrendously awkward. I had no idea how much my body had adapted to playing the violin in the last year. When I tried to get the other side to do some of that stuff, it said "Admiral-san!! Are you out of your f---ing MIND??!?!")

But... since the main thing is find out if your left hand is strong enough to hold a bow, you can at least experiment that much. If it is, that would be an available option. You might miss out on some of the fancier techniques that require tricky finger work, like tremolo, but from your description of your playing, it'd probably be a long time before that was an issue. And hey, you could always use both tricks and swap off as needed.   

Actually the problem with my fingers is that when touched there is pain shooting up but I have tried using only two fingers or trying to cushion my fingers with tape. I have thought about learning to play left handed but that would require moving the bass bar, replacing the nut, chin rest, bridge and sound post. I might just make a violin a lefty and if I don't use it I'll give it away.

KindaScratchy said
Welcome back, Kevin! And best wishes for your health issues and your violin playing.

Thank you all for the great welcome back. As for the playing I am back to the beginning. I am back to twinkle twinkle. My hand has lost a great deal but I still love it. I have started on my true love of repairing violins. I have quite a few here that I started on and left. Several of them are quite nice violins and others, well they make music. I want to finish my Scott Cao violin made in California. I may be a travesty but the neck was broken and being a horse person I have a horse head neck to put on it.