Suggest Treatment For Severe Lower Back Pain While Walking

I have trouble standing and walking short distances. My lower back will start to hurt and I become humped over as I try to walk further or stand longer. I worked at a grocery store for 22 years on cement floor and we worked out of a grocery cart most of the time so I counted on the cart when I walked all those yrs at my job. I have a lot of arthritis everywhere. I have screws in both hips on the thinnest part of my femur bone and I tore the cartilage in my left knee. The chiropractor helps for a day. I could get an epidural shot in my back but I don t know if it would work. I went to a orthropedic doctor and he took x-rays and MRI and said I was normal for my age of 75. My family doctor will only let me take naproxen for pain relief and it only works for about a week. I have taken it morning and evening around the clock but doesn t help much. I have balance problems and sometimes my feet don t seem to work right and my left one likes to drag and I don t always pick it up good. I don t know what to do.