A hinge for a brace comprises a tensioning element such as an inelastic cord for applying a restorative force to the hinge. A tensioning mechanism, preferably a hydraulic spring, tensions the cord as the hinge is moved from a rest position to a loaded condition. A tensioning member having a peripheral cam surface applies a tensioning force to the cord as the hinge is moved out of the rest position. The tensioning block and the anchoring block may be operatively geared together along an arc of motion so as to provide a generally symmetrical motion of the tensioning and anchoring portions relative to the gusset. When an external force is applied to move the hinge from the rest position the tension on the cord loads the spring, and when the external force is removed the spring applies a restorative force to move the hinge back to the rest position. Optionally the tensioning member may be configured to be disengaged and reengaged by an external actuator.