I I've been on dialysis for 12 yrs and I developed bone disease years before being on dialysis. Is it possible that my bone disease got worse?

Quite possible. There is mineral and bone disease in people who have chronic kidney disease and end stage kidney disease requiring dialysis. Maintaining calcium, phosphorus and parathyroid hormone levels are extremely important for bone health. Even otherwise there are other reasons as to why the bones may get involved in dialysis patients.