The knee pain and bone weakness of the elderly may be caused by osteoporosis, cartilage damage of the knee joint and rheumatoid arthritis, etc., which can be treated with medication. 1. Osteoporosis: With the gradual increase of age, the body’s calcium loss, resulting in a gradual decrease in bone mass, the elderly will appear osteoporosis, knee pain and bone weakness and other symptoms. You can choose bisphosphonate drugs, such as sodium hydroxyethylphosphonate, under the guidance of your doctor. 2. Knee joint soft tissue injury: Knee joint soft tissue injury caused by trauma, degeneration and strenuous exercise, you can choose to take chondroprotectors and other drugs for treatment, such as chondroitin sulfate and so on. 3. Rheumatoid arthritis: rheumatoid arthritis inflammation destroys joint tissues, leading to knee pain and bone weakness symptoms, patients can choose to treat osteoarthritis under the guidance of the doctor for treatment of drugs, such as glucosamine hydrochloride. When the elderly appear knee pain bone weakness and other symptoms, it is recommended to go to the hospital in time for examination and diagnosis, and under the guidance of the doctor to take medication, not unauthorized use of drugs, so as not to aggravate the condition.