Aims: To determine whether femoral neck length, a risk factor for hip fracture, is likely to increase in the coming decades in normal elderly New Zealand women.
Methods: Femoral neck length was measured from dual-energy x-ray absorptiometry scans of the proximal femur in white women aged 19-88 years (n = 211). Since this length remains constant throughout adult life, it is possible to predict future trends in this index in the elderly, from its measurement at the present time in younger adults.
Results: Femoral neck length was inversely related to age (p = 0.018) such that a 3.7 mm (5.7%) difference occurred over the age-range of this sample.
Conclusions: Femoral neck length in elderly New Zealand women is likely to increase in the coming decades. As a result of the dependence of hip fracture risk on femoral neck length, future age-adjusted hip fracture incidence will increase by about 50% over the next 50 years unless significant public health initiatives are taken, either to increase bone density or to reduce fall frequency.