C.R.S. § 8-46-307

(1) In any determination of permanent disability, the employer or the employer’s insurance carrier shall receive no credit or benefit for the reduction of disability of any claimant employee under the “Workers’ Compensation Act of Colorado” directly attributable to a compensable accident or disease when such reduction of disability is accomplished by expenditures from the medical disaster insurance fund, unless it shall have been determined by a preponderance of the evidence: (a) That the claimant employee had refused hospital, surgical, and medical services under the “Workers’ Compensation Act of Colorado” necessary to reduce the employee’s disability voluntarily offered by the employer; or (b) That the claimant employee had reached maximum improvement as determined by the director prior to the filing of the application for payments from the medical disaster insurance fund.