The compressive deformation behavior of normal and degenerated cancellous bones is visualized during a static compression test. The normal principal compression trabeculae are broken, owing to flexural buckling. The osteoarthritic process results in a change of the cancellous structure. That is, the ratio of thickness per unit length and the ratio of thickness per unit width of the principal trabeculae increased by degeneration. Because the degenerated principal trabeculae increase buckling resistance, fracture occurs owing to stress concentration at the node of the individual trabecula. The degenerated cancellous bone exhibits only the constant deformation resistance without the flexible deformation that would adjust to the change of loading in a hip joint.
