Expected frequency of biomechanically adverse values of proximal femur geometric variables for fracture risk in the East Slovak female population (epidemiological study)

Abstract

The geometric configuration of the proximal femur predicts the risk for fracture by fall independently of bone mineral density (BMD). The objective of the study was to determine the expected frequency of biomechanically adverse and extremely adverse values of proximal femur geometric variables alpha angle, theta angle, and HAL, increasing the risk of a femoral neck fracture by fall, in the East Slovak female population. DXA (dual energy X-ray absorbtiometry) measurements of the left proximal femur were obtained and analysed from sample 3151 East Slovak women aged 20-89 years, [Formula: see text] = 58.9 years, SD = 11.1, with risk factors for the development of osteoporosis, with osteopenia and osteoporosis using bone densitometer (Prodigy - Primo, GE, USA). Measured variables: 1. geometric variables: alpha angle, theta angle, HAL (hip axis length) and 2. biomechanical variable: FNS (femoral neck strength). 1. Goodness-of-Fit Test χ(2)-test (Chi-Squared Test). 2. Logistic regression. Biomechanically adverse value of angle α>6.869° can be expected in 10% of the East Slovak female population; extremely adverse value of angle α>12.3° in 1%; biomechanically adverse value of angle θ>129.405° in 20%; extremely adverse value of angle θ>132.290° in 10%; biomechanically adverse length of HAL>109.930 mm in 20%; extremely adverse length of HAL>113.015 mm in 10%. The study brings the first data determining the mean values and 95% C.I. for proximal femur geometric variable values in the East female Slovak population. Biomechanically adverse values of proximal femur geometric variables are values higher than the upper limit of 95% C. I. and these findings enable now physicians to identify the individuals at risk and at high risk of hip fracture by fall.