Would be a lot cooler if it it were powered externally. Still, it seems a bit risky with the "barbell"s, because they’re simultaneously inside, and outside of the barrier, so if the coating isn’t 100% perfectly adhered to all 3 of them, there’s chance for body fluid to get inside and cause problems, or come back out. And if it moves around when you move, that’s probably gonna work on the bond between the stainless steel "barbell"s, and the coating.
Also not entirely certain about stainless steel inside the body. Maybe if it’s a nitrogen steel, but even then, the steel may still cause a reaction.
I really want to like that implant though, because it seems very interesting.