Appeal from a decision of the Workers’ Compensation Board, filed May 19, 1977, as amended by a supplemental decision filed October 6, 1977. The primary issue in this case was whether or not the employer had any knowledge of a condition of the employee—an operation whereby a bone was *762removed from her wrist—which was a permanent impairment. The board found upon "the credible testimony” that the employer had no good faith belief of a previous permanent impairment. There is substantial evidence to sustain the finding of the board. Decision affirmed, with costs to the Special Fund against the employer and its insurance carrier. Greenblott, J. P., Sweeney, Kane, Larkin and Herlihy, JJ., concur.