Second to Fourth Digit Ratios in Plastic Surgery

INTRODUCTION The second to fourth digit ratio (2D:4D) is the ratio of the length of the index finger (2D) to the length of the ring finger (4D), and it is the most powerful human dimorphic digital ratio combination.1 The 2D:4D is a well-recognized physical marker of intrauterine androgenic steroid exposure with the index finger length being a measure of the amount of intrauterine estrogen exposure and the ring finger length acting as a measure of intrauterine androgen exposure. Low digit ratios have been shown to be associated with increased assertiveness and risk taking,2 aggression, sporting prowess,3 and improved visuospatial ability. Good visuospatial awareness has been explicitly linked to surgical performance, and it is now utilized as an essential criterion in the selection process for surgical training.