Correlation of Anthropometric Measurements, Strength, Anterior Cruciate Ligament Size, and Intercondylar Notch Characteristics to Sex Differences in Anterior Cruciate Ligament Tear Rates

Abstract

We performed a prospective study based on the hypothesis that physiologic differences exist between men and women in strength after adjustments for body weight; that the size of the anterior cruciate ligament is proportionate to the strength of its antagonists, the quadriceps muscles; and that women have a relatively small anterior cruciate ligament, thus predisposing them to a disproportionate number of anterior cruciate ligament injuries. One hundred matched high school basketball players, 50 male and 50 female, were evaluated with anthropometric measurements, body fat analysis, muscle strength evaluation, and magnetic resonance imaging measurements of the intercondylar notch and cross-sectional area of the anterior cruciate ligament at the outlet. The male players were taller and heavier than their female counterparts, although they had 11% less body fat. Male players had statistically greater quadriceps and hamstring muscle strength than female players, even when adjustments were made for body weight. With adjustments for body weight, the size of the anterior cruciate ligament in girls was found to be statistically smaller than in boys. There was no statistically significant difference in the notch width index between the sexes. The study data support our hypothesis that sex differences in anterior cruciate ligament tear rates are caused primarily by several interrelated intrinsic factors. Most importantly, stiffness and muscular strength increase stress on the anterior cruciate ligament in female athletes. The anterior cruciate ligament, when adjustments have been made for body weight, is smaller in female athletes, and therefore, probably does not compensate for the lack of stiffness and strength.

Risk factors for Anterior Cruciate Ligament injury in skeletally immature patients: analysis of intercondylar notch width using Magnetic Resonance Imaging

“…While there is still disagreement in the literature as to whether variations in notch geometry related to differences in gender or limb dominance, play a contributing role in ACL injuries, we did not find a difference in NWI with respect to gender, involved side, mechanism of injury or type of sport engaged in at the time of injury [7,12,13,18,21,22].…”

“…This difference may be caused by different imaging techniques used for the evaluation of NWI. Two studies measuring NWI using MRI [8,21] have shown much higher values for normal adult populations than values reported in radiographic studies [2][3][4][5][6][7]20].…”

Is Noncontact ACL Injury Associated with the Posterior Tibial and Meniscal Slope?

“…The PTS of the bony tibial plateaus frequently is mentioned for its association to noncontact ACL injury [3,18,40,45]. It is defined by a tangent line to the respective tibial plateau and a line perpendicular to the longitudinal axis (LA) of the tibial bone that averages 10°(± 3°) on radiographs [9,13,16,19].…”

Validation of Porcine Knee as a Sex-specific Model to Study Human Anterior Cruciate Ligament Disorders

“…The findings then were compared with published data from human knees. Results Female pigs had smaller bicondylar widths (2.9 mm, ratio = 0.93, effect size = À1.5) and intercondylar notches (width: 2.0 mm, ratio = 0.79, effect size = À2.8; area: 30.8 mm 2 , ratio = 0.76, effect size = 2.1; index: 0.4, ratio = 0.84, effect size = À2.0), steeper lateral tibial slope (4.3°, ratio = 1.13, effect size = 1.1), smaller ACL (length: 2.7 mm, ratio = 0.91, effect size = 1.1; area: 6.8 mm 2 , ratio = 0.74, effect size = À1.5; volume: 266.2 mm 3 , ratio = 0.68, effect size = À1.5), thinner medial femoral cartilage (0.4 mm, ratio = 0.8, effect size = À1.1), lower ACL yield load (275 N, ratio = 0.81, effect size = À1.1), and greater AP knee laxity at 30°( 0.7 mm, ratio = 1.32, effect size = 1.1) and 90°(0.5 mm, ratio = 1.24, effect size = 1.1) flexion compared with their male counterparts. These differences were significant for all parameters (p B 0.04).…”