20 CFR §10.104

1. (a)A recurrence should be reported on Form CA-2a if that recurrence causes the employee to lose time from work and incur a wage loss, or if the employee experiences a renewed need for treatment after previously being released from care. However, a notice of recurrence should not be filed when a new injury, new occupational disease, or new event contributing to an already-existing occupational disease has occurred. In these instances, the employee should file Form CA-1 or CA-2.
2. (b)The employee has the burden of establishing by the weight of reliable, probative and substantial evidence that the recurrence of disability is causally related to the original injury.
   1. (1)The employee must include a detailed factual statement as described on Form CA-2a. The employer may submit comments concerning the employee's statement.
   2. (2)The employee should arrange for the submittal of a detailed medical report from the attending physician as described on Form CA-2a. The employee should also submit, or arrange for the submittal of, similar medical reports for any examination and/or treatment received after returning to work following the original injury.
3. (c)A claim for recurrence of disability is not available where OWCP has issued a loss of wage-earning capacity determination. Under that circumstance, the only method for claiming additional wage loss compensation is through a request to modify that determination. However, OWCP is not precluded from adjudicating a limited period of disability following the issuance of a loss of wage-earning capacity decision, such as where an employee has a demonstrated need for surgery.