extremity vs shinbone

extremity

noun
  • A limb (“major appendage of a human or animal such as an arm, leg, or wing”). 

  • The most extreme or furthest point of something. 

  • A hand or foot. 

  • An extreme measure. 

shinbone

noun
  • The inner and usually the larger of the two bones of the leg or hind limb below the knee 

  • A segment of an insect's leg. 

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