The palm of my left hand has a 3rd degree keloid scar that is tightening. Any suggestions? (photo)

I burnt my hand on a floor furnace as a toddler and had plastic surgery when I was 12 to help alleviate scar contraction. It seems to be tightening more now (40 years later). Is there a dynamic palm spreading splint available? Do you know of a custom splint maker? It effects my work (graphic design).