Sorry to hear of troubles of loved ones, hope they get better real soon!
I've for just about a month had pain from my left back, down my arm where half my hand is numb. They think two problems. Under shoulder my pain in arm pit from over extending, was thought to be tendonitis. Other attributed to upper spine vertabra in neck and pinched nerve due to thinning of space between vertebra and holes in vertebra thinning narrower where nerves pass through. This due to long term arthritis of the spine. Shock and needle like pain in hand sucks. Drugs for pain help, but that's no answer. Next after X-rays is Nerve Conduction Test and MRI. No real treatment yet, but hanging upside down with inversion table helps but just arm only. Put the bike project to make a cover for parade usage on hold and riding in the woods too. Try to keep cool though and visited the creek near by when it was up near 100 F.