My spine is completely fused and there are other ortho/neurological problems with hips and feet.

However, I do fine on the treadmill as long as I hold on to the arm rests. I realize this changes what muscles are getting the most workout but it still gives me a good cardiac workout, so don't forego that treadmill because of the other problems!

I need that workout (otherwise I'd be almost completely sedentary) for my heart health.

Also, of course, healthy eating, minimal or no alcohol, watching your BP and weight, and (need I say?) avoiding smoking!