Editing Ski boot (section)

===External frames===
The ski boot provides three functions; protecting the foot from the elements, providing a mounting point for the binding, and transmitting forces between the leg and the ski. In theory, there's no reason these have to be combined in a single unit, and several designs have split these functions up. One example is the [[Nava System]] from the 1980s, which used a soft boot that clipped into custom bindings, and an arm that extended up from the rear binding to wrap around the leg and provide lateral control.<ref>Clint Swett, [https://web.archive.org/web/20121104053604/http://sportsillustrated.cnn.com/vault/article/magazine/MAG1065468/index.htm "Have Your Ski Boots Got You Sore? A Comforting Change Is Now Afoot"], ''Sports Illustrated'', 17 November 1986</ref>