Da Italiano a Inglese Arte/Letteratura Modi di dire/Massime/Proverbi context of a short story

Hi Everyone.
I am having trouble with this expression:"quasi tiro il gambino", which I can't find in any of the dictionaries I use, including Treccani. The context is a science fiction story in which the character is riding along on her quadricycle with sails when she hits a rock which causes the back sail to flap loose and hit her in the back of the neck:
"L'angolo di scotta si mette a sbarellare e io me lo becco qui sulla nuca che quasi tiro il gambino". From context I am guessing it means "knocks me out" or "does for me", or some other idiomatic expression for being killed, but I am hoping someone can give me an exact explanation. Thanks in advance, Isobel