Suggest Remedy For Painful Arms And Joint

i am a 42 year old man, i play am playing badminton for many years now, for fittness. for the last one year i am suffering from a peculiar pain in my upper arm, at the joint. This only happens at when i lift my hand at particular angle. I cannot use much force with my hand. i have seen many orthpaedic doctors, who advised particular exercises, But the problem still hasnt been solved. i would like to know what could be the reason for this & how can my problem be solved.