I'm fused all over, in my fifties, and determined to be fit. I've had 15 surgeries including one on each ankle, four knee (all on my left knee), four back surgeries (two of them fusions, now fused from L3 through S1), three shoulder surgeries (two left, one right), one neck fusion (C3 through C5), and one toe fusion (right big toe). There will probably be more...is what it is.