Normative forearm torque data: a cross-sectional study on the Korean population

Purpose: Establishing normative values for forearm rotational torque is essential for assessing upper limb function and guiding therapeutic interventions. Previous studies have focused on Western populations, leaving a gap in data for Asian populations, which may exhibit different muscle strength characteristics. This study aimed to measure forearm rotational torque in healthy Korean adults to establish normative values based on age, sex, and hand dominance. Methods: In total, 500 healthy Korean adults (217 males and 283 females), aged 20 to 69 years, were recruited and divided into decade-based age groups. Exclusion criteria included prior treatment for upper limb trauma or neurological damage. Using a digital torque gauge with a T-shaped handle, pronation and supination torques were measured in a standardized neutral position for both hands (dominant and nondominant). Statistical analyses were performed using SPSS 26.0, with significance set at p<0.05. Results: The average pronation torque of the dominant hand was 33.00±11.57 kgf•cm (3.36±1.18 N•m), and the supination torque was 32.38±12.01 kgf•cm (3.30±1.22 N•m). The difference was not statistically significant (p>0.05). The dominant hand exhibited significantly higher torque values than the nondominant hand in both pronation and supination (p<0.05). Males demonstrated higher torque values than females across all age groups (p<0.05). The highest average torque values were observed in individuals aged 30 to 39 years. Conclusion: This study provides normative data for forearm rotational torque in healthy Korean adults, highlighting that the dominant hand exerts significantly more torque.