3D distribution of cortical bone thickness in the proximal humerus, implications for fracture management. CT imaging is commonly used to gain a better understanding of proximal humerus fractures. the operating surgeon however has a limited capacity to evaluate the internal bone geometry from these clinical CT images. our aim was to use clinical CT in a novel way of accurately mapping cortical bone geometry in the proximal humerus. we planned to experimentally define the cortico-cancellous border in a cadaveric study and use CT imaging software to map out cortical thickness distribution in our specimens.Title
Introduction
Fractures of the proximal humerus represent a major osteoporotic burden. Recent developments in CT imaging have emphasized the importance of cortical bone thickness distribution in the prevention and management of fragility fractures. We aimed to experimentally define the CT density of cortical bone in the proximal humerus for building cortical geometry maps. With ethical approval we used ten fresh frozen human proximal humeri. These were stripped of all soft tissue and high resolution CT images were then taken. The humeral heads were then subsequently resected to allow access to the metaphyseal area. Using curettes, cancellous bone was removed down to hard cortical bone. Another set of CT images of the reamed specimen was then taken. Using CT imaging software and a CAD interface we then compared cortical contours at different CT density thresholds to the reference inner cortical contour of our reamed specimens. Working with 3D model representations of these cortical maps, we were able to accurately make distance comparison analyses based on different CT thresholds.Introduction
Methods