Topic = (leg OR hip OR knee OR ankle OR foot OR (lower
AND (limb* OR extremity OR body))) AND Topic = (power* OR
active) AND Topic = (aid OR assist* OR improve* OR augment* OR
enhance* OR climb stairs OR reinforce*) AND Topic = (ortho* OR
exoskeleton* OR wearable robot* OR portable robot* OR robot suit)
AND Topic = (control* OR validation*) NOT Topic = (post stroke).