I Have Developed A Place On Both Sides Of My

I have developed a place on both sides of my lower back, about 5" or so below my waist, where I have pain; I can now feel something like bony lumps on my pelvis in these areas. Can you tell me what this can be? A previous x-Ray showed an area of concern at L4/L5, and I have a significant amount of osteoarthritis. Thank you for any suggestions you can provide.