A bad back doesn’t seem worth dying over. Especially someone who obviously considered themselves an “activist”. Why give up? Did he advocate suicide for people with poor health or chronic injuries? It is sad.
1)Arthritis, in pain so bad, only unconsciousness would relieve it.
2)Loss of bowel control. Completely, no indication, no recourse but a diaper, if he could feel it.
3)Paralysis. Sooner or later the spinal cord will be blocked, pressured, cut or pinched. Then you are wheelchair bound with drugs and a bag attached. Or like Christopher Reeve
4)Loss of upper brain functions. Some of the drugs work exceedingly well for a number of connected maladies, but the higher brain functions suffer. And memory gets worse.
5)Depending on the break and the portion of the cord that gets pinched, a repirator may be neccessary, and eating will be fluids only.
In other words total medical care given by others.
Not a pretty future for anyone.
Not really what you would call 'living'.