From what i'm Reading your paperwork is being processed,part of that process is that they have requested on your behalf a temporary rating for your knee and back of 100% that is good because the conditions you have you deserve a 100% rating. if you have submitted all of your paperwork to the VA you're OK it appears that more than likely you are going to get your temporary 100% and then in the future you will have to go to another C&P for them to decide if your condition has improved if it's about the same more than likely you will then get your 100% to become permanent. Your claim looks good just make sure you go to any appointments they ask you to go to.And keep all your paperwork in one location where you can get it when needed.Also the additional items they are looking at is a good thing,let them look at everything they want to it will benefit you.and anytime you send in paperwork make sure you keep a copy for yourself.