There is a perk you can get that allows you to cure sprains instantly with a splint (or a cast). There are perks to reduce the effects of falling and therefore your chance of getting a sprain or break. You have options to fix this problem. It's all about what is more important to you for your enjoyment.
So I guess I'm saying it isn't broken, from my perspective.
One big pet peeve of mine used to be that if you had too many, or too severe, afflictions it was possible to be rooted in place, unable to move or attack or anything. THAT was a major annoyance and anti-fun but it seems that they fixed it.
EDIT: effects, doh