Orientation / Anisotropy

Orientation of materials

Ideally materials are isotropic and homogeneous.

• A material is called isotropic when its properties are the same in x-y-z direction.
• A material is said to be homogeneous if it is made of the same material throughout.

Bone and bone grafts however are anisotropic and non-homogeneous . Cancellous bone is actually extremely anisotropic and non-homogeneous. Cortical bone, on the other hand, is approximately linear elastic, transversely isotropic, and relatively homogenous.

Figure : Influence of tissue anisotropy on stress strain curves.