Section 10.400 - What is total disability?(a) Permanent total disability is presumed to result from the loss of use of both hands, both arms, both feet, or both legs, or the loss of sight of both eyes. 5 U.S.C. 8105(b) . However, the presumption of permanent total disability as a result of such loss may be rebutted by evidence to the contrary, such as evidence of continued ability to work and to earn wages despite the loss.(b) Temporary total disability is defined as the inability to return to the position held at the time of injury or earn equivalent wages, or to perform other gainful employment, due to the work-related injury. Except as presumed under paragraph (a) of this section, an employee's disability status is always considered temporary pending return to work.