Elderly patients with weak legs, can be improved by exercising leg muscle strength, joint cavity injection of sodium vitrate, etc., as follows: First, exercise leg muscle strength: exercise leg muscle strength, such as quadriceps, calf triceps, etc., can be assisted by sandbags for resistance knee flexion and extension activities, as well as heel lift training, can enhance leg muscle strength, the patient’s leg weakness symptoms will be significantly The patient’s leg weakness will be significantly improved, and it takes 3-6 months of exercise to have obvious therapeutic effect. Second, the joint cavity injection of sodium vitreous acid: if the knee joint disease caused by weak legs, the knee joint should be targeted for treatment, such as joint cavity injection of sodium vitreous acid to reduce joint surface wear, relieve joint inflammation, reduce joint pain, can make the leg muscle strength to a certain extent to restore. With early and active treatment, the symptoms of weakness in the legs of elderly patients will often be relieved soon. Patients should avoid overexertion and protect the knee joint in their normal life in order to prevent the recurrence of symptoms.