My grandfather is 80 year old. He finds difficulty in walking, as his knees are locked as everyone says. Whenever he walks, its very hard for him to walk without any support and his knees hurt alot. Is there anyway that his knees gets better and he could walk without pain. He is using chair or stick as a support. His medical history: he is a heart patient: -nitroglycerin controlled release tablets 2.6 mg -aspirin he is also a blood pressure patient. Please help.