Sex determination by the length of metacarpals and phalanges: X-ray study on Egyptian population.

Measurements of hand bones length have been shown to be sexually dimorphic in many nationalities. The aim of this study is to assess the accuracy of sex determination from the length of all metacarpals and phalanges of right and left hands using X-ray radiographs and to develop a discriminant formula that can be used in the Egyptians. One hundred Egyptians are included in the study (50 adult males and 50 adult females) in the period from December 2009 to January 2011 with mean age 31.60 ± 9.44. Each is subjected to X-ray radiographs on both hands. The results reveal that males have significantly greater mean values than females for all metacarpals and phalanges of both hands and the Egyptian population has greater measurements in comparison to the other ones (e.g. Turkish and European Americans). In addition there is no significant difference between the right and the left hands in either males or females. The correct classification reached an accuracy of 88%-94% by using both hands, while that for right hand only is 88% and 88%-90% for the left hand only. Regarding the accuracy of each bone, the present results revealed that 1st DP & PP and 3rd and 4th MC in the right and left hands are the best bones that can be used in correct sex determination. It is concluded that the length of metacarpals and phalanges (especially the 1st DP & PP and 3rd and 4th MC) could be used for sex determination. The right hand could be used as the left hand in determination of sex. Also the X-ray radiographs are good non invasive and simple tool in the determination of sex from the hand bones. Furthermore the regression equation for both hands and each hand separately is specific to Egyptian population and should be used after validation of the results in other ones.