Ambidexterity in left-handed and right-handed individuals and implications for surgical training.

Surgical training has historically been geared toward right-handed individuals. This could cause mentors to perceive left-handed students and residents as being more difficult to train. This study examined whether differences in dexterity exist between left-handed and right-handed individuals and the implications this may have on surgical training. Recent literature suggests that surgical training may need to be updated to train left-handed students more effectively. In this prospective, crossover study, 50 right-handed and 50 left-handed individuals of varying ages and occupations were evaluated using the O'Conner Tweezer Dexterity Test. Participants were timed while they used flat-tipped forceps to pick up 1″ brass metal pins and sequentially place one pin each in 100 pinholes 1/16″ in diameter on a 21″ × 12″ board. Participants completed this exercise with their dominant hand followed by their nondominant hand. Nondominant hand dexterity was measured by dividing the nondominant hand completion time by the dominant hand completion time, with a higher percentage associated with higher ambidexterity. Using the Student's two-tailed t test, we found that left-handed individuals had an 97.2% congruence between dominant and nondominant hands while right-handed individuals had a 71.6% congruence (P < 0.001). In conclusion, our results show that left-handed individuals have a greater degree of ambidexterity than their right-handed counterparts. These results suggest that any perceived difference between left-handed and right-handed surgical residents may not be due to innate skill or dexterity, but rather a combination of external influences.