hamstring vs leg irons

hamstring

noun
  • One of the great tendons situated in each side of the ham, or space back of the knee, and connected with the muscles of the back of the thigh. 

  • The biceps femoris, semimembranosus, and semitendinosus muscles. 

verb
  • To lame or disable by cutting the tendons of the ham or knee; to hough. 

  • To cripple; to incapacitate; to disable. 

leg irons

noun
  • A fetter or shackle attached at the ankle. 

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