Lindsey Vonn announced on her Facebook page that she won't compete in the Sochi Olympics:
Vonn explained that she's had to overcome "having no ACL" and that her knee is "just too unstable to compete at this level."
Vonn tweeted that she was "devastated" by her choice.
Vonn also added that she'll undergo surgery soon so that she can prepare for the World Championships "at home in Vail" in February 2015.
Cate Sevilla is the UK managing editor for BuzzFeed and is based in London.
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