Figure 1: (a) A longitudinal section of the middle shaft of the femur of a control rat showing an outer fi brous layer, periosteum (star), and an inner layer facing the marrow cavity, endosteum (arrow). The bone matrix contains many Haversian canals with blood vessels with concentric lamellae surrounded by osteocytes. (b) A longitudinal section of the middle shaft of femur bone of a control rat showing normal cortical width of the shaft. (c) A longitudinal section in the head of the femur of a control rat showing normal architecture of the trabeculae of the inner cancellous bone (arrow) and bone marrow spaces. (d) The head of the femur of normal rat showing normal thickness of bone trabeculae (arrow). (a, c) Hematoxylin and eosin-stained sections; (b, d) binary image morphometric measurement, × 400.