Actually, I haven't seen any so I don't know that there is a huge difference. I would actually wager guards get injured slightly more often.
I am looking more at his specific injuries, acl, hip, back both in regard to lateral effectiveness and the probability of re-injury. So I see him being less likely to get hurt at guard with fewer reach blocks and quick leg kick stuff at snap.
In Luce tua Videmus Lucem KRK