Relationship between Sex Hormones and Anterior Knee Laxity across the Menstrual Cycle

摘要: Purpose: To comprehensively quantify through daily, serial measures changes in knee laxity as a function of changing sex-hormone levels across one complete menstrual cycle. Methods: Twenty-five females, 18–30 yr, body mass index <= 30, who reported normal cycles (28–32 d) over the past 6 months participated. Participants were tested daily cycle; 5–7 cc venous blood withdrawn to assay serum estradiol, progesterone, and testosterone. Knee was measured amount anterior tibial displacement at 133 N, using standard arthrometer. evaluate relationship sex hormone concentrations, multiple linear regression model with possibility time delay performed on each individual subject group whole. Results: Individual equations revealed an average 63% variance explained by three hormones their interactions. All significantly contributed prediction equation, substantially greater when considered. On average, changed approximately 3, 4, 4.5 d after testosterone, respectively. When females analyzed group, only 8% sex-hormones levels. Conclusion: Changes mediate cycle. However, strength this relationship, relative contribution hormone, associated are highly variable between women. This variability is consistent cycle characteristics among