Title : Changing structure of the surgical neck of humerus in Chinese postmenopausal women
Abstract:
Introduction: The anatomical distribution of cortical bone in the surgical neck of the humerus may be essential in determining resistance to fracture. The aim of the study is to investigate the spatial distribution differences in cortical bone, and the effects of aging and menopause on cortical properties in surgical neck.
Methods: Cortical bone mapping (CBM) was used for the analysis of computed tomography data from 78 women aged 20 to 86 years. Six regions of interest (ROI 1-6) were defined in medial and lateral column of surgical neck after color maps for each proximal humerus were created. Cortical parameters, including cortical thickness (CTh), cortical mass surface density (CM), and the endocortical trabecular density (ECTD) were measured.
Results: In the pre- and post-menopausal women, proximal part of lateral columns (ROI4) had thinner and less dense cortices, compared to the lateral column (P < 0.05). Compared with premenopausal women, the CTh, CM and ECTD in ROI 4 was lower by 26.74%, 28.44% and 1.27%; in ROI 5 by 16.67%, 24.26% and 1.06% in postmenopausal women (P < 0.05). However, CTh and CM in ROIs of medial column did not differ between the pre- and post-menopausal groups. The CTh in ROI 4-5 in lateral column was negatively associated with age, whereas no relationship was observed in medial column.
Conclusions: The cortical thinning was found in the lateral column of surgical neck, impacted by aging and menopause.
