Leg pain in the elderly can be caused by many reasons, and osteoarthritis pathological changes are the primary cause of leg pain in the elderly. Osteoarthritis has three main characteristics: the first is morning stiffness, the patient feels pain in the lower extremities when waking up, no strength, when down to the ground after three minutes of action, can be relieved; the second is sitting for a long time, when standing, feel pain in the knee joint, after action can be relieved; the third is up and down the stairs weakness; another characteristic is the elderly osteoarthritis fear of cold, so also known as the old cold leg.