This case is reported because it appears to be the first case in the literature in which this accessory bone was implicated in a traumatism of the foot. REPORT OF CASE J. J. Mc., aged 30, an electrician, sprained his right ankle in April, 1921. I saw him three months later, at which time he was still complaining of pain and disability in the right foot. He localized the pain on the dorsum, in front of the external malleolus. He stated that occasionally a swelling appeared in this situation after use. He walked with a slight limp. There was considerable tenderness on the dorsum in front of the external malleolus. Occasionally a crepitus could be elicited in the anterior subastragaloid region. The mobility of the subastragaloid region was moderately restricted. A roentgenogram in the lateral view showed what at this time was interpreted as being a fracture through the processus