Appeal from a decision of the Workmen’s Compensation Board, filed August 8, 1974. While claimant was assisting her employer, an oral surgeon, she experienced pain in her lower back as the result of bending over a patient while surgery was being performed. The pain became more intense during that day, particularly when she was required to hold a *988patient’s head to restrain its movement. The next day she was unable to straighten her back and was hospitalized for a myelogram which disclosed disc involvement. A laminectomy was thereafter performed. The employer and its insurance carrier controvert the present award on the ground that claimant did not sustain an accident within the meaning of the Workmen’s Compensation Law. The only medical evidence in the record is the report of claimant’s orthopedic surgeon who found causal relation. The strain of bending and other physical movements required of claimant in the performance of her duties in assisting her employer in his surgical procedures may constitute an accidental injury in a proper case, and here the board’s finding that such an injury actually occurred is adequately supported by substantial evidence (Matter of Kort v Ingrasci, 46 AD2d 715). There is nothing to contradict the finding of causal relation in the report of claimant’s expert and the carrier offered no medical proof although it had numerous opportunities to do so. Under the circumstances, the board, in the exercise of discretion, could refuse the request to reopen the case for further development of the record on the question of causal relationship (Matter of Layton v Interstate Heating, 45 AD2d 779). Decision affirmed, with costs to the Workmen’s Compensation Board. Herlihy, P. J., Greenblott, Kane, Main and Larkin, JJ., concur.