A device for rehabilitating or strengthening the ankle includes a plank that is connected by a transversely oriented hinge and a longitudinally oriented pivot, as well as a pair of compression springs at its forward end. The connections of the plank to the underlying base limit the plank to motion in two directions about two axes, thereby providing four types of therapeutic ranges of motion, including dorsiflexion and plantar flexion, eversion and inversion. A transversely slidable foot rest enables the user to hold device 21 in position with one foot while using the plank of the device to rehabilitate the other foot.
