The bloke is made of glass. He ruptures a groin when he farts. He's either the most unlucky player on the planet or there is something wrong with his body or rugby playing technique to cause so many major injuries.
He was brought into rugby at a senior level when he was still very young indeed and was a suicidly aggressive tackler no matter how big the opponent. Even before the injuries began there were people who questioned how long his body would take that kind of punishment. Shame as he comes over as a really decent guy and is hugely dedicated. Perversely though, his not being around when the retirement finally comes, might actually commit England to playing a more expansive style of rugby.