Hello, I have studied your case. I think she is having knee arthritis. You will have to get her x ray first and it will tell us if she needs to get a survey for it. If knee arthritis s is advanced than surgery is a good option and it can be done by a expert joint replacement surgeon. It is very much successful surgery and patient can walk after three to four days of the surgery. If she is not willing of surgery that she needs to take few precautions. She should avoid squatting and cross leg sitting. She should take regular calcium and vitamin D 3. Also hot water fomentation and tubifix for knee are beneficial. She should also try to loose some weight. I hope this answers will be useful for you. Let me know if there is any other follow up questions. Thanks