Neb. Rev. Stat. § 48-141

All amounts paid by an employer or by an insurance company carrying such risk, as the case may be, and received by the employee or his or her dependents by lump-sum payments pursuant to section 48-139 shall be final and not subject to readjustment if the lump-sum settlement is in conformity with the Nebraska Workers' Compensation Act, unless the settlement is procured by fraud, but the amount of any agreement or award payable periodically may be modified as follows: (1) At any time by agreement of the parties with the approval of the Nebraska Workers' Compensation Court; or (2) if the parties cannot agree, then at any time after six months from the date of the agreement or award, an application may be made by either party on the ground of increase or decrease of incapacity due solely to the injury or that the condition of a dependent has changed as to age or marriage or by reason of the death of the dependent. In such case, the same procedure shall be followed as in sections 48-173 to 48-185 in case of disputed claim for compensation.