In this case, the Workers’ Compensation Appellate Commission further addressed the issue of what constitutes a medically distinguishable condition needed to satisfy the Rakestraw requirement for pre-existing conditions. The Commission espoused that pain alone is not conclusive evidence of a medically distinguishable injury, however an injury producing continuing pain or pain that is different from an employee’s pre-injury condition will constitute a medically distinguishable condition. Further, if an injury produces continuing pain such that it causes impaired performance of pre-injury activities, that can also constitute a medially distinguishable injury.