When a compensable injury combines with a noncompensable injury, disease, or other condition, the organization shall award benefits on an aggravation basis, on the following terms:
1. In cases of a prior injury, disease, or other condition, known in advance of the work injury, which has caused previous work restriction or interference with physical function the progression of which is substantially accelerated by, or the severity of which is substantially worsened by, a compensable injury, the organization shall pay benefits during the period of acute care in full. The period of acute care is presumed to be sixty days immediately following the compensable injury, absent clear and convincing evidence to the contrary. Following the period of acute care, the organization shall pay benefits on an aggravation basis.2. If the progression of a prior compensable injury is substantially accelerated by, or the severity of the compensable injury is substantially worsened by a noncompensable injury, disease, or other condition, the organization shall pay benefits on an aggravation basis.3. The organization shall pay benefits on an aggravation basis as a percentage of the benefits to which the injured worker would otherwise be entitled, equal to the percentage of cause of the resulting condition that is attributable to the compensable injury. Benefits payable on an aggravation basis are presumed to be payable on a fifty percent basis. The party asserting a percentage other than the presumed fifty percent may rebut the presumption with clear and convincing evidence to the contrary.4. When an injured worker is entitled to benefits on an aggravation basis, the organization shall still pay costs of vocational rehabilitation, burial expenses under section 65-05-26, travel, other personal reimbursement for seeking and obtaining medical care under section 65-05-28, and dependency allowance on a one hundred percent basis.