Background and Purpose: The upper extremities, especially the arms and shoulders, are used intensively in racquet sports. In this work, our primary aim is to compare bone mineral densities (BMDs) between dominant and non-dominant arms in racquet athletes. We then compare BMDs between athletes playing racquet sports and non-athletes.

Methods: A total of 24 racquet sports male athletes active for at least 10 years (age, 22.46 \pm 2.41 years) and 22 non-athletes (age, 21.45 \pm 1.74 years) voluntarily participated in this study. The BMDs of the humerus, radius, and ulna of the dominant and non-dominant arms of both groups were measured by dual energy X-ray absorptiometry.

Results: The BMDs of the proximal humerus and humeral shaft of dominant arms were significantly higher than those of non-dominant arms in athletes (19.85% vs. 12.02%); while statistically, no statistically significant difference in BMDs was found in non-athletes (P > 0.05). The BMDs of the dominant proximal humerus and humeral shaft of athletes were higher than those of non-athletes (P 0.05). Non-dominant arm BMDs did not differ between the two groups (P > 0.05).

Conclusion: BMD differences observed between the right and left arms of athletes indicate that, rather than confounding factors like genotype, right-/left-handedness, participation in racquet sports may influence BMDs in the related extremities.