Thanks for the info and links - pain had not an issue at any point, pre or post op and must articles are based on pain disrupting sleep. This is not the case. I know knees can be pretty painful, but hips generally no so. I suspect that the REM pattern was changed and it is roughly the time of propofol infusion so I am wondering if there is a possible link to either dose or length of exposure. Meeting with surgeon for 6 week post op and we will certainly talk about this and the decrease in quality of life that is brings. Thanks again for your input