My husband is 84 years old, is 5 7 tall and weighs 166 lbs. His parents had a history of strokes, but he has never had one, to my knowledge. He has atrial fibrillation, is diabetic, and has a pacemaker. He takes medicine for diabetes, irregular heart rhythm, high blood pressure, and cholesterol. Sometimes after he has been standing for a while and attempts to resume walking, his legs won t move normally and he cannot stand on his own. Then, I have to hold him up while he takes each step to prevent him from falling. What could be causing his legs not to work after prolonged standing?