Absolute Serum Hormone Levels Predict the Magnitude of Change in Anterior Knee Laxity across the Menstrual Cycle

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
David H. Perrin, Provost and Executive Vice Chancellor (Creator)
Sandra J. Shultz, Associate Professor (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: This study aimed to determine whether absolute sex hormone concentrations predict the magnitude of knee joint laxity changes across the menstrual cycle. Twenty-two females (18–30 years, body mass index =30), who reported normal menstrual cycles for the previous 6 months were tested daily across one complete menstrual cycle for serum levels of estradiol (E = pg/mL), progesterone (P = ng/mL), and testosterone (T = ng/dL), and knee joint laxity (KLax = mm displacement at 134N) measured with a standard knee arthrometer. The change in KLax across the cycle (maximum–minimum), and minimum (early follicular) and peak (postovulatory) hormone concentrations were recorded for each subject. A stepwise linear regression determined if the minimum, peak, or absolute change in hormone concentrations would predict the magnitude of change in KLax across the cycle. KLax changed on average 3.2 ± 1.1 mm across the menstrual cycle (range, 1.5–5.3 mm). Minimum levels of E (39.9 ±11.8 pg/mL) and P (0.61 ± 0.27 ng/mL), coupled with peak concentrations of E (199.6 ± 54.9 pg/mL) and T (22.5 ± 10.5 ng/dL) explained 57.6% of the change in KLax across the cycle. Greater absolutechanges in KLax were observed in response to peak E and T levels when minimum E concentrations were lower and minimum P concentrations were higher in the early follicular phase. The absolute minimum concentrations of E and P in the early follicular phase appear to be important factors in determining the sensitivity of the knee joint’s response to changing hormone levels.

Additional Information

Publication
Journal of Orthopaedic Research, 24(2), 124-131
Language: English
Date: 2006
Keywords
hormone pulsatility, estradiol, progesterone, testosterone, joint behavior