That picture sure brings back some fond memories

Looks like a nice, clean cut. There really shouldn't be too much worry about injecting bacteria or foreign matter into the wound with a cut from a sharp knife: The possibility exist, but it is usually not a problem. However, a cut to the bone and any deep / large cut should be checked by a doctor. Some fibers (such as tendons) may need surgery to be fixed properly, and infection in the bone structure is serious stuff. Fix either of those problems NOW and it's no hassle, wait and you'll really have to fight it hard.

I don't worry at all about cuts that aren't too deep or to the bone, don't actually have cut through stuff as tendons or aren't obviously badly infected.



Er, no, only against tenatus. Which, as stated in other posts, is a rather horrible way to die. http://en.wikipedia.org/wiki/Tetanus Stepping on a dirty, rusty nail is one a classical way of getting it. Unless you've dipped your knife in horse droppings there's really not much chance of getting it in a knife cut. But still, you really want to take that shot to exclude tenatus from the list of possible infections.