Please Advise

I am a 70% SC Vet , I am rated 20% for lumbar strain (I fell of the top of a commo rig on a 2 1/2 truck and landed across the trailer hitch . I have been having trouble with my lower back and legs for years , I am 50% rated for flat feet (they did not say but I belive this to be caused by my gait change) I have started having ed and Incontinence issues , My primary ordered new xrays an it shows increased wear and tear , she has ordered another mri  4 years ago I tried to connect periphial  neuropathy and radiculopathy to the lumbar strain . I was denied because the VA said I did not have radiculopathy diagnosed (it is refered to as my having it in my VA medical records ) and that it was not caused by lumbar strain . I have seen many places that this is . 

 My question is this I want to try again . The back problems have increased I realize that the lumbar strain is predicated on ROM . I also know that this is very much how the CP goes . So an increase here is very hard . I want to know how I can file for the sciatica and incontinence issues and should I try for my hip pain and knee pain My knees have been xrayed and I have arthritis this was also mentioned in my service records and I have never filed for it . Any advice is welcomed as this time I intend to cross my t and dot my I before I file . I do not want to fail because I did not present my evidence . I am still working but This is starting to effect my work and evry aspect of my life .