Hi! I'm new here, but I have a question. My boss had his hip replaced about 10 years ago and has recently had problems walking when he first gets out of a chair. He's wondering if it's time to replace the polyethyene in his replacement. Has anyone had this done? How invasive is it? What is the recovery time with something like this? Are there certain symptoms that lead to to know it's time to have things checked out? He is thinking maybe he just needs to go see the mechano-therapist (kind of like a chiropractor, but not) to adjust his back instead. Any ideas? Thanks for the info, this is a great site to look for info!