S Plane To Z Plane. An anatomical plane is a hypothetical plane used to transect the body in order to describe the location of structures or the direction of movements In human and animal anatomy three principal planes are used The sagittal plane or lateral plane (longitudinal anteroposterior) is a plane parallel to the sagittal suture It divides the body into left and right The coronal plane or.
In practice it’s usually easier to work out ${\bf n}$ in a given example rather than try to set up some general equation for the plane.