disarticulate vs unfasten

disarticulate

verb
  • To disjoint. 

  • To amputate (a limb) at a joint without cutting the bone. 

unfasten

verb
  • To come unloosed or untied. 

  • To detach from any connecting agency or link; to disconnect. 

How often have the words disarticulate and unfasten occurred in a corpus of books? (source: Google Ngram Viewer )