When you put the kind of torque on your lead knee like Tiger does, it's not hard to get hurt. You want to remember that those guys don't play the way we do. We might hit a bucket now and again along with a weekly round. Those guys are hitting maybe 300 balls on a given day at the range. Add on the competetive strokes and we're takin' a lot of reps. Now do this for twenty years and see what happens to your body. This is why some players take a long time to get back to "normal" after an injury. To get it back, you have to practice hard. If you're coming back from an injury, it takes time to get to the point that you're doing that, so the game suffers. When it comes to Tiger, I think he's got a double whammy. Most golfers mature after 30. Tiger did at 20. Now at 35, in some ways he may have the body of a 45-50 year old golfer even though he's a workout nut. I've even heard a few commentators mention that his typical 7 mile runs may have contributed to the problems. They know more than I do.
In closing, yes, you can get injured playing golf. In fact, I was playing one round and reached into my cart for a beer and....................
Good Luck!
Ric at Joes