I received a L3/L4/L5 fusion in 1963. Highly successful.

Even survived a 100+mph motorcycle accident. Walked away from it.

But now it appears that I've arrived at being old & have thoracic degeneration "issues" that are giving me leg problems.

I'm seeking information on what happens when the lumbar area has been immobilized & those lumbar forces now get pushed into the thoracic area. After a while (48 years) I suspect the poor ol' thoracic guys are a tad over stressed.

Where do I look for information?