title: Medial tibiofemoral-joint stiffness in males and females across the lifespan.
abstract: Analyzing ligament stiffness between males and females at 3 maturational stages across the lifespan may provide insight into whether changes in ligament behavior with aging may contribute to joint laxity.
  
  
  
  To compare the stiffness of the medial structures of the tibiofemoral joint and the medial collateral ligament to determine if there are differences at 3 distinct ages and between the sexes.
  
  
  
  Cross-sectional study.
  
  
  
  Laboratory.
  
  
  
  A total of 108 healthy and physically active volunteers with no previous knee surgery, no acute knee injury, and no use of exogenous hormones in the past 6 months participated. They were divided into 6 groups based on sex and age (8-10, 18-40, 50-75 years).
  
  
  
  Ligament stiffness of the tibiofemoral joint was measured with an arthrometer in 0° and 20° of tibiofemoral-joint flexion. The slope values of the force-strain line that represents stiffness of the medial tibiofemoral joint at 0° and the medial collateral ligament at 20° of flexion were obtained.
  
  
  
  When height and mass were controlled, we found a main effect (P < .001) for age group: the 8- to 10-year olds were less stiff than both the 18- to 40- and the 50- to 75-year-old groups. No effects of sex or tibiofemoral-joint position on stiffness measures were noted when height and mass were included as covariates.
  
  
  
  Prepubescent medial tibiofemoral-joint stiffness was less than postpubescent knee stiffness. Medial tibiofemoral-joint stiffness was related to height and mass after puberty in men and women.
authors: Lynchburg College, VA.
authors: Patricia
authors: P
authors: Aronson
authors: Arie
authors: A
authors: Rijke
authors: Jay
authors: J
authors: Hertel
authors: Christopher D
authors: CD
authors: Ingersoll
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001696:Biomechanical Phenomena; D002648:Child; D003430:Cross-Sectional Studies; D004548:Elasticity / Q000502:physiology; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D017888:Medial Collateral Ligament, Knee / Q000502:physiology*; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D055815:Young Adult
keywords: arthrometry; hormones; medial collateral ligament; sex differences