Been denied by HMO, read this:
If you've been denied by your HMO, there is still hope. I've been hearing more and more about people obtaining an Independent Review after going through the appeals process and being granted the surgery. It may be time consuming, but if you have significant health problems that justify the surgery and if you don't have the option of changing health insurances, this may be an avenue. There is a WI member by the name of Clare Nagel that was successful with this venture. See the link below for the Independent Review Board process:
http://oci.wi.gov/pub_list/pi-203.htm
I too, was denied by insurance. I appealled, unsuccessfully and finally ended up self-paying in Ensenada Mexico. I researched my surgeon and hospital and ended up going there. I will never regret it. My surgery healed very quickly and the nurses were so very attentive, it was incredible.
(just another option)
Good luck!