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• A position in labor in which the woman is in the dorsal posture, with hips at edge of table and lower extremities hanging.

1898 - American pocket medical dictionary
By Willam Alexander Newman Dorland

• A position used in obstetrics to enlarge the pelvic diameters. The patient is on the back on a table with the thighs and legs hanging over the table's edge. [Gustav Adolph Walcher, German obstetrician, born 1856.]

1916 - Appleton's medical dictionary
By Smith Ely Jelliffe