The surgery was done after he fell, aggravating the injury he sustained in a quad bike accident in 2003.
"My singing voice is still good, but after three surgeries, stem cell treatments, endless sessions of physical therapy, and recently even groundbreaking Cybernetic Hal treatment, my body is still physically weak," writes Osbourne, who is thus trying rehabilitation with the help of new robotic technology.
The now-cancelled tour was supposed to start in Finland in May and has previously been moved several times due to Ozzy Osbourne's fall injuries and covid-19, the BBC reports.
In 2020, he also shared that he was already diagnosed with Parkinson's disease in 2003.
Now he is giving up his tour plans.
"I feel genuinely touched by how you patiently kept the tickets during all this time," writes Osbourne, who thanks his fans for "a life he could never even dream of."