I read something somewhere yesterday (I meant to make a note of exactly where but I forgot!) that described someone’s body as being ‘wracked with pain’.
This is a pretty common and understandable mistake, because both ‘wracked’ and the word that should have been used – ‘racked’ are unusual words and tend only to appear in cliche-like phrases.
‘Wrack’ is an archaic version of ‘wreck’ and it is pretty much only used correctly these days in the saying ‘to wrack and ruin’. Someone’s body could, I suppose, eventually be ‘wracked’, but what is usually meant is ‘racked’. This comes from the gruesome torture device known as the ‘rack’, on which one’s body was put under strain almost to breaking point and sometimes beyond.