Secular change in the torsional angle of Japanese femora

The torsion angle of the Japanese femora of the early modern Edo (early and late series) and modern periods were measured. In the modern period, this angle is in males and females significantly larger than in the early series of the early modern Edo period and shows a gradual increase from the early modern Edo to the modern period. It is was always larger in females than in males. This change may be in part due to sedentary habits or living posture of the latter half in the early modern Edo period.