Back trouble

I've been suffering from shoulder pain for last 4 years after an injury and can come back at anytime (touch wood its ok at the moment) but i had a lot of trouble with it last September to December. this also affected my upper back . Ive had lower back problems for the last 10 years and come and go and could be something to do with the way i sleep . my biggest problem is my knee god damn on a bad day i cant even walk. I'm like you zulu if i sit down for too long i seize up and it a pain. i, one of the ones who just wont go to the doctor either so that dont help . need to get this knee sorted out though .

after i ride on the MTB and i sit down i seize up and cant move with my lower back .