When did treatment change?

When I was younger I threw out my back. The doctor told me the only way it would resolve is to lie on my back, take advil and do nothing until the pain resolves. When I had the sciatica I was told to do PT, stretches and being active. When I told my dr. what I was told 20 years ago he said I'm lucky my back didn't seize up. My mother in law said she had a slipped disc in the 1970s and again she was told to lie down and do nothing for a week except use the bathroom.