A quick n' dirty (as usual) test in Blender at retopologizing and manually (pun intended) rigging a great scan: ["Hand"](https://skfb.ly/6GW88) by [Artec 3D](https://sketchfab.com/artec3d), available under CC-attribution. The base mesh used for the retopology is [Low Poly Human Hands (All Quads)](https://skfb.ly/6NUy9) from [Jeremy E. Grayson](https://sketchfab.com/JeremyGrayson), also available under CC-Attribution. Based on an original "concept" by Michelangelo, from the Sistine chapel's ceiling ;)