Reproducibility of dynamic balance and anterior tibiofibular gap measurements in men and women: A menstrual cycle-based longitudinal study.

Abstract

Background: The reproducibility of dynamic balance is an essential component of athletic performance and injury prevention, although it is affected by sex differences. This study aimed to confirm the reproducibility of repeated dynamic balance measurements and ultrasonography assessments of the anterior tibiofibular gap that may contribute to changes in dynamic balance for each sex.

Methods: This was a longitudinal study involving 48 feet, with 12 men and 12 women. Measurements for men were obtained four times, approximately once a week, and for women, once during each of the four periods of the menstrual cycle (menstrual, follicular, ovulation, and luteal phases). The measures included dynamic balance in a single-leg jump with forward landing and the anterior tibiofibular gap measurement in standing and sitting positions; rate of change in the anterior tibiofibular gap was calculated from the values in standing and sitting positions.

Results: The intraclass correlation coefficient for dynamic balance was excellent for men at 0.936 (0.881-0.969) and good for women at 0.843 (0.708-0.925). Regarding the anterior tibiofibular gap, the intraclass correlation coefficient for standing and sitting were 0.999 (0.997-0.999) and 0.998 (0.996-0.999), respectively, in men; and 0.976 (0.955-0.988) and 0.991 (0.984-0.996), respectively, in women, with excellent values for both sexes. Whereas no significant changes in dynamic balance and rate of change in the anterior tibiofibular gap were observed in the four measurements in men (p > 0.05), there was a significant variation in women (p < 0.05).

Conclusions: While reproducibility of dynamic balance and anterior tibiofibular gap measurements was high overall, it was lower in women than in men. Women exhibited variations in these measurements during each period of the menstrual cycle, peaking during ovulation. Recognizing these fluctuations could inform injury prevention strategies tailored to sex-specific differences in dynamic balance and ligament extensibility.