Suggest Treatment For Osteoarthritis

Hi . I have been told i have ostioarthitis and need 2 replacement knees. i was told this about 8 years ago and am in constant pain and can't walk far or stand for long periods. Reciently i have been getting sharp pains in my left leg it feels like i have broken a bone and it goes away after about half an hour. Is there anything i can do to relieve this without surgery as i have been told that i am too young (53). I am a heating engineer but no longer carry out any kneeling or climbing.