The crash occurred with less than three kilometres left in the 218-kilometre stage from Fougeres to Tours in the Loire valley.
Henderson, in the Lotto-Belisol team, also ended up at the bottom of the pile.
"What a pile up wow!...Was like being at bottom of a rugby scrum," Henderson tweeted.
"Thought i broke elbow bt only stitches needed.@Lotto_Belisol boof down!"
Team Sky rider Edvald Boasson Hagen came off much worse, breaking his right shoulder blade and has dropped out of the tour.
Germany's Marcel Kittel overtook Mark Cavendish at the line to win stage, while yellow jersey holder Chris Froome avoided the crash to protect his big lead.
Henderson sits in 150th place in the overall standings, with Bauer 11 spots behind him in 161st.