If you are totally disabled for a serious medical condition--from spinal fusion or other surgery, to shoulder or knee replacement, to diabetes or cancer, or any other serious disabling condition--one of the most significant parts of your case is your EOD, or established onset date.
The Social Security Administration will determine your EOD (established onset date), either administratively, or by a law judge at a hearing. But the date that you, the disabled person, believes your disability began--your AOD (alleged onset date), is vitally important in helping the Social Security Administration determine when you should begin receiving benefits.
How does the administration or law judge at a hearing determine the date your disability began? By analyzing your application for SSDI, and your work history, and your medical records, including doctors's reports, test and scan results, surgery operative reports, and any other evidence from your medical record.
Being totally disabled and unable to work is distressing enough. The process and system for getting SSDI should not be as complicated as it is. However, if you understand how the system works you will be able to increase your chances of winning your case and of receiving social security disability benefits as expeditiously as possible.