The forces applied by female and male chiropractors during thoracic spinal manipulation

Background: On average, women weigh less, have a smaller frame, and are less muscular than men. Since the peak thrust force applied during spinal manipulative treatments can be quite high and must be reached in a very short period of time, one might question the physical ability of women to generate such high forces. Objective: To study the forces generated by male and female chiropractors as they deliver spinal manipulation to the thoracic spine. Methods: Fourteen male and 14 female experience-matched chiropractors participated in this study. They each manipulated 1 of 9 asymptomatic male adult subjects of similar height and weight. The clinicians were asked to manipulate a transverse process in the vicinity of T4 and T9. Any technique could be used as long as the treatment thrust was in a posterior to anterior direction and the hand contact fit onto the sensor pad (area = 100 cm(2)). Results: There were no significant differences (P < .05) between male and female chiropractors for any measurements in the upper thoracic area. For the lower thoracic manipulations, the preload forces for the male chiropractors were significantly greater (P < .05) than those for the female chiropractors. The remaining variables were the same between the 2 groups. Conclusions: Female chiropractors produce, from a mechanical point of view, similar manual treatments as their male colleagues.