Hi Ryan. The knees are notorious for having the least amount of blood flow than any other spot in our body. Sitting all day at a desk definitely makes this even less so. I work at a desk job as well and I get stiff knees. I recommend getting up more often and doing a couple minute walk a few times through the day. As for the back...this is also one of my biggest issues. I try to focus on my posture as much as possible and usually put a good cold pack on it after work if I find I was straining and/or hunching a lot. Sometimes the way we sit can cause some slight inflammation to the soft tissue if we are pushing against our regular posture. A girl I work with is looking into buying a brace that will keep her shoulders aligned and back straight. Something like that might be a good idea for you to look into to. I wish you all the very best!