Positive influence of long-lasting and intensive weight-bearing physical activity on hip structure of young adults.

The aim was to analyze the associations between high-intensity and long-lasting weight-bearing sports with hip structure in young adults. One hundred and seventy-two subjects aged 17-28 yr were divided into 4 groups: 40 athlete women (10.2 ± 2.2 h/wk), 30 control women, 67 athlete men (11.4 ± 3.6 h/wk), and 35 control men. The nondominant femur, lumbar spine, and whole body were scanned by dual-energy X-ray absorptiometry to assess bone mineral content (BMC) and bone mineral density (BMD). Hip structure analysis (HSA) software was applied to evaluate cross-sectional area, cross-sectional moment of inertia, and section modulus at the femoral neck, intertrochanter, and femoral shaft regions. All the BMC and BMD values were significantly higher in athletes of both sexes compared with controls (p < 0.05). Most of the hip structural parameters were significantly higher (p < 0.05) in athletes compared with controls. Most of the differences were maintained after adjustments for height, weight, and calcium intake. Positively significant correlations were observed between HSA parameters and physical activity variables in both sexes (r > 0.32; p < 0.05). Partial correlation suggested that the hours of practice appeared to have a greater influence than the years of practice on hip bone geometry. These results suggest that external mechanical loading is a strong determinant of hip bone structure when weight-bearing physical activity is commenced before puberty and maintained during adulthood.

The QUALYOR (QUalité Osseuse LYon Orléans) study: a new cohort for non invasive evaluation of bone quality in postmenopausal osteoporosis. Rationale and study design.

The diagnostic performance of densitometry is inadequate. New techniques of non-invasive evaluation of bone quality may improve fracture risk prediction. Testing the value of these techniques is the goal of the QUALYOR cohort. INTRODUCTION: The bone mineral density (BMD) of postmenopausal women who sustain osteoporotic fracture is generally above the World Health Organization definition for osteoporosis. Therefore, new approaches to improve the detection of women at high risk for fracture are warranted. METHODS: We have designed and recruited a new cohort to assess the predictive value of several techniques to assess bone quality, including high-resolution peripheral quantitative computerized tomography (HRpQCT), hip QCT, calcaneus texture analysis, and biochemical markers. We have enrolled 1575 postmenopausal women, aged at least 50, with an areal BMD femoral neck or lumbar spine T-score between - 1.0 and - 3.0. Clinical risk factors for fracture have been collected along with serum and blood samples. RESULTS: We describe the design of the QUALYOR study. Among these 1575 women, 80% were aged at least 60. The mean femoral neck T-score was - 1.6 and the mean lumbar spine T-score was -1.2. This cohort is currently being followed up. CONCLUSIONS: QUALYOR will provide important information on the relationship between bone quality variables and fracture risk in women with moderately decreased BMD.