A device for measuring spinal stiffness comprises a framework supporting a roller that is rolled over the surface of the back. The device creates and records a trajectory across a subject, using a control board and the roller, and moves the roller along the trajectory while applying a force to the subject using the roller and records displacement of the object in the direction of the force. A stiffness map is created using displacement as a function of force. Motors may be used to move the roller through three axes.