Abstract: A therapeutic limb brace for gradually extending flexion contractures of a patient's knee or elbow, and for increasing dorsiflexion of the foot. Upper and lower frames of the brace are incrementally adjustable in both length and lateral spacing for fitting limbs of various proportions, the frames having side members that are comfortably spaced apart from the limb. Control of knee joint movement, for example, is provided by one or more tension springs that can be selectively hooked in parallel between the upper and middle frames for dynamic therapy, a stop member for preventing hyperextension, and a plurality of index holes that can be used in static therapy for locking the frames in fixed angular relation or for limiting movement to a selected angular range. A turnbuckle substituted for one of the springs provides gradual movement at high mechanical advantage.