Bone mineral content (BMC), bone areas (BA) and bone mineral density ( BMD) of the proximal femur in healthy Chinese men (N=202) and women (N=507 ) 21-70 years old were measured to investigate sexual differences in densitometry of the femur. Densitometric values at the femoral neck, trochanter and Ward's triangle were generally greater in men than women of the same age. While BMD decreased with aging with similar slope of 0.2-1% per year, the actual readings were 10-15% lower than that of Caucasian people of same age and gender for Chinese men and women. Furthermore, with increasing age, trochanteric BA increased in women but not in men, and femoral neck BA increased in men but not in women. These different trends of change in bone dimensions were independent of weight or height and may reflect structural difference at the proximal femur and imply differences in mechanical strength between both genders
