I’m also curious as to what the tendons in my hands look like and whether or not it might not be worthwhile to see a hand specialist. Part of this is pure curiosity on my part, just to learn what the anatomy of the tendons in my own hand looks like. Part of it is also to determine whether it is not simply impossible for me to maintain tone in my middle finger’s distal knuckle while reaching out with my fourth finger.
I strongly suspect it is, because I cannot imagine it being any other way. When I see people maintain tone in the middle finger’s distal knuckle when placing the fourth finger, I literally feel as if I’m watching a Martian with a triple-jointed leg jumping rope. Even trying makes my palm and the back of my hand burn. The middle finger distal knuckle doesn’t become weak when I try to reach out with my fourth finger. It becomes dead.
And again, nothing else causes pain like this. Nothing. At all. I can crochet for an entire two-day weekend, and I feel no pain. I type for hours, and I feel no pain. I can play piano for hours, and I feel no pain. This one simple movement makes my palm and the back of my hand burn, and it is demanded in conventional harp technique.
I would like to visit a hand specialist just to see what they can tell me about the very particular anatomy of my hand. If they can’t specifically show me the anatomy of the tendons in my hand, then I will not visit twice. If I can’t learn why my hand will not execute this movement, I will stop taking lessons and continue as an autodidact, or I will see if my teacher is open to the idea of just assigning me the pieces that she would have assigned me originally, and just letting me figure out fingerings that work for me — and if that means a cornucopia of thumb slides, then so be it.