A knee brace adapted for placement over at least a posterior side of a leg and comprising a first posterior frame member, a second posterior frame member connected to first frame member, and a posterior resilient hinge device located at or near a first end portion of the first frame member. The hinge device is arranged to urge the first and second frame members into a predetermined alignment. The hinge device can be arranged for selectively locking the second frame member at an angle relative to the first frame member, and permitting rotation of the second frame member relative to first frame member within a range of predetermined angles.