Taking your age in consideration and considering your x ray picture described by you I am of opinion that you are suffering from osteoarthritis. It s a age related condition and tends to worsens with activities. treatment for this condition is both non operative and operative. Usually people are managed non operatively by exercise to strengthen muscles around knee, lifestyle modifications like not to sit cross legged and ablosihing or modifying activities which cause stress in knee joint, Use of walking aids like walking stick and adequate pain relief. However if nonoperative treatment fails and pain is so severe that affect patients life activities very much we advise surgery In my opinion please visit orthopedic surgeon so that he can asses you clinically , radiologically and provide appropriate treatment considering severity of your illness.