Causes. Leg length discrepancies can be caused by poor alignment of the pelvis or simply because one leg is structurally longer than the other. Regardless of the reason, your body wants to be symmetrical and will do its best to compensate for the length difference.
Date of Onset. When the Social Security Administration (SSA) refers to a disability applicant's Date of Onset, they are referring to the date that a Social Security Disability applicant became disabled. When you fill out your Social Security Disability claim forms, you will be asked to provide the date your disability began.
As pertains to Social Security Disability Insurance (SSDI), your date of entitlement to disability is generally five months after the date on which you made your intent officially known. The rationale behind this is that SSI is needs based.