I injured my finger while climbing, so I designed this splinter to stabilise the finger for better recovery. 

It aims to stabilise the finger, so that tendons can recover. Please note that im no medical expert whatsoever, so please use this at your own risk. 

This version is slightly left oriented and I use it on my left ring finger. You may want to mirror it  for a better fit, if used on other fingers.

I printed the model in size:

X 107%

Y 105%

Z 115% 

You should print some iterations to check for the best fit. 

Even though enough stability is given in PLA, I used PC Carbon blend for optical reasons and  stability/weight improvements. Also the matte texture of the material helps to prevent the finger to get moist under the splinter.
 

No Supports needed.