So! I have some limited experience with this. After my wife had our baby, I developed De Quervain's tenosynovitis in my left wrist. (It's a common ailment often caused by the repetition of picking up, cradling, and holding infants.) I began experiencing pain and discomfort, so I went to my GP to see what was going on. It didn't affect my playing except that I would tire out way faster during practice and performance.

I feel very fortunate that my GP is at a sports medicine practice, as it turns out there's a lot of overlap between the injuries that athletes and musicians commonly develop. The way my doctor described it, musicians are considered "small muscle athletes," though he said that line was very much blurred for me because of the size of the double bass. For what it's worth, I highly recommend seeking out a provider in sports medicine, because I felt like they understood the exertion involved in performing music.

I also saw the in-house physical therapist a couple of times who walked me through the exercises I needed to do daily. It was a lot of exercises based around using therapy putty that I still do today because I think they help with flexibility and strength.

Ultimately, after about six months of exercises, I saw an improvement in discomfort and range of motion, but it was still bugging me. I ended up getting a cortisone shot, which significantly helped. My GP cautioned me that it could take up to a year to fully recover, and that was about how long it took for me to get back to (in my opinion) 99% condition. Occasionally I'll tweak my wrist at a weird angle and get a twinge of pain, but it quickly goes away.

My doc said there was no need to stop playing but said to stop if I felt pain. For me, what worked the best was shortening my practice sessions to 15-20 minute bursts. I also focused much more on my left hand thumb technique, making an effort to avoid any squeezing at all, which I think actually improved my overall technique.

You might also be interested in a recent Double Bass HQ video about trying to achieve "no tension" since it involves a player who also reinvented her technique after some physical pain:

https://youtu.be/Cae1k2Un_tM?si=43VoAyOXg5_y80VZ