Determination of Gender from Measurement of the Femur

 

Multiple Measurements in Americans

 

Patient population: 47 females and 70 males in the Tennessee Data Bank, composed both of African and European Americans

 

score =

= (0.45623 * (epicondylar breadth in mm)) + (0.61152 * (midshaft sagittal diameter in mm)) + (0.57968 * (midshaft transverse diameter in mm)) – (0.21425 * (midshaft circumference in mm)) – 50.5667

 

Interpretation:

• A score > 0 indicates male gender.

• A score < 0 indicates female gender

 

Performance:

• 91% of skeletons were correctly sexed using the equation.

• Performance may be suboptimal at the age extremes.

 

Multiple Measurements in Japanese (Hinihara)

 

Patient population: 48 adult males and 40 adult females from Japan

 

score =

= (bicondylar length in mm) + (9.85 * (vertical diameter of head in mm)) + (11.99 * (minimum transverse diameter of the shaft in mm)) + (4.13 * (bicondylar width in mm))

 

Interpretation:

• A score > 1431.82 indicates male gender.

• A score < 1431.82 indicates female gender

 

Performance:

• 96.2% of skeletons were correctly sexed using the equation.

• Performance may be suboptimal at the age extremes.

 

Femoral Head

 

The maximum diameter of the femoral head correlates with gender. The presence of articular cartilage adds about 2 mm relative to the diameter for dried bone. The following is presumably for dry bone based on the collections used.

Diameter in mm	Probable Gender
> 45 mm	male
43 – 45 mm	indeterminate
< 43 mm	female

derived by combining the data on page 176

 

Performance:

• The presence of degenerative joint disease may increase the maximum diameter of the femoral head.

 

Multiple Femoral Measurements in Whites (Taylor and DeBennardo)

 

male score =

= (2.83443 * (circumference in mm)) + (0.83965 * (length in mm)) - (3.28170 * (anterioposterior diameter in mm)) - 270.04932

 

female score =

= (2.42105 * (circumference in mm)) + (0.79874 * (length in mm)) - (2.72106 * (anterioposterior diameter in mm)) - 232.29536

 

where:

• I could not find reference for the sites of the measurements or adjustments made for the presence of cartilage. In the implementation I am assuming midshaft measurement for the circumference and sagittal diameter.

 

If male score > female score, then male.

If female score > male score, then female.

 

probability of being in male group =

= EXP(male score) / (EXP (male score) + EXP(female score))

 

probability of being in female group =

= EXP(female score) / (EXP (male score) + EXP(female score))