If you ever have to file for disability you will no doubt become an expert on the subject, with an SSI PhD by the time its over. I received excellent service from the people at Allsup. http://www.allsup.com/ . It cut through the paperwork for me and I hope the link is useful to you.
A short word on filing with your insurance carrier if you are lucky enough to have Long Term Disiability.
Be prepared to to have all your doctors sign letters for your file. Keep copies of all x-rays,scopes and Physical Therapy reports.
You may think your disability is obvious but that will not matter without the correct amount of documention. Good Luck.