My mom has rheumatoid arthritis for many years. After taking dmard, her knee joint pain is almost gone. But recently she is suffering from a burning sensation in the side of her ankle joint and whenever she tries to get up from a sitting position for walking or something, she can't stand or step up properly. What to do? She takes sazo 500 od, conjoint 3d od as medications. And she works out and walks everyday as per doctor's advice.