An Oxford don with the wonderful name of Lancelot Hogben wrote a series of books on the English language some years ago. In one of them he said that the "Grecian Bend" was a pose favored by models back in the days of the Gibson Girl. The model stood arms akimbo, hands well to the back, and leaned back and to one side. Sand hogs adopted the phrase to describe nitrogen narcosis (the bends) because the pain usually hits in the kidneys first, causing the sufferer to assume that pose. As in "Willie's got the Grecian Bends".