I was looking for information on my upcoming disc replacement surgery and came across this site where they show surgeries in real time ( well first in real time) and you can even email questions for the surgeon. If anyone is interested they have several surgeries on the list one being a knee replacement. I found it very informative and not too gory.
http://www.or-live.com/ololrmc/2003/index.cfm?r=orlive
check it out if you are interested or thinking about surgery it answers lots of questions
spineuniverse is also a good place to go for info on that type of surgery. Hope it goes well for you :)