Lots of such qualifying details are not uttered, because they are assumed according to certain maxims which govern constructive conversation among rational people.
I didn't realize some still consider logic based on Greek gods.
You'd be happy, then, to note the modernized version also included in the article.
This procedure has been done on monkeys in the 70's. It might not give this man any control over his new body, but at least he won't suffocate to death from spinal muscular atrophy.
That is implied, otherwise first 'head transplant' would be done centuries ago by some dr Frankenstein.