Medial Collateral Ligament Stiffness In Males And Females

Abstract

The Medial Collateral Ligament (MCL) is the most commonly injured ligament in the knee joint. In sports medicine, concern exists regarding ligament stiffness and structure and the differences between males and females. Research has shown gender differences in the stiffness of the anterior cruciate ligament but little attention has been given to the differences in the genders regarding the tensile strength of the MCL. PURPOSE To compare the force/strain curve and resultant slope of the MCL in uninjured knees and determine if there is a difference in males and females. METHODS Forty-five healthy volunteers (26 females and 19 males; height = 170.6 ± 7.75 cm; weight = 74.2 ± 15.14 kg; age = 23.2 ± 3.96 years) with no history of knee surgery or knee injury in the past six months were tested on a multipurpose arthrometer device. A coin toss determined which knee would receive a valgus force of 100–120 Newtons first. The force was applied to the lateral aspect of the knee in full extension. Slope comparisons were analyzed using ANOVA with repeated measures. RESULTS There was a significant difference in the slope of the force/strain curve between genders (F1,43 = 10.84, p = .002). The resultant slopes of male MCLs were significantly stiffer than females in extension: the mean slope for males with the knee in full extension was 20.29 and for females it was 17.79. When weight and height were added as covariates, there was still a statistical difference between the genders (F1,43 = 8.01, p = .007). CONCLUSIONS There is a difference in the stiffness, as measured with a force/strain curve and resultant slope, between the Medial Collateral Ligaments in males and females.