First of All, Welcome!
Then a bit of reinforcing of what has already been said:
Glass implants: you want them away from the bones and in the middle of as much meat as you can.
Flex implants: these can be as close to bones as you want, but preferably with the least amount of movement as possible (counter intuitively as to the name)
Happy to elaborate further if needed.
I like your thinking, but ultimately tendon movement should not be an issue:
The problem with movement is if you end up bending the implant over and over.
Tendons moving beneath the implant would not actually deform it. It will just push the implant towards a resting point where it ends up less “touched”. but that’s it.
Remember that we implant in the “middle of the skin layer”. No implant location should be so deep as to cause the implant to be entangled on the tendons enough that each movement bends the implant…
As a reference, I have a P4 Flex implant for around 4 years now (I think? I’m terrible with dates). It even has a custom “LED Flex/Nail” implant that got discontinued because these things are so damn fragile that almost every one failed. Yet, mine is still going strong.
And I climb, work with my hands, practice martial arts, etc… on a daily basis.
TL;DR your concerns made perfect sense, but the actual interaction with the tendons isn’t as intense, because the implants are meant to be completely above them. With a whole layer of skin/pocket acting as a Manteau
(finger placements might be more complex, hence less reccomended)
I would say… it’s a possible location. maybe even further up on the forearm itself.
But it will depend a lot on your daily activities.
For example: for me, I would have f*cked my implant already on the many times I get my wrists on rocks or on a twist grab, or even because of how I tend to rest the inside of my wrist on the edge of my desk while typing.
But it might suit you, depending on your activities…
Similar thing from the external side of the wrists… I had a piercing there once that made me aware of how many times I hit my wrists on… everywhere!
But ultimately, these are only guides and our experiences. your habits should be what really weighs in…