Yea, but people getting knee injuries semi-commonly, I think deserves an examination into what's causing them and how training can be adjusted so it doesn't happen..
I think 2 very common injuries are knee injuries and, among beginners learning forward rolls, shoulder separations from landing on the top of the shoulder.
Gregory, I did a preliminary survey of 101 dojos on knee injuries a number of years ago. The link to the summary page, which then links to the full write up is
I did it during the yr off the mat in surgery/rehab. I've never again had that kind of concentrated time to do the second survey I wanted to. Someday....