title: Differences in lower extremity anatomical and postural characteristics in males and females between maturation groups.
abstract: METHODS
  Descriptive, cross-sectional.
  
  
  OBJECTIVE
  We compared lower extremity anatomical characteristics in males and females between different maturation groups.
  
  
  BACKGROUND
  Sex differences have been observed in lower extremity anatomical characteristics. While the reasons contributing to these sex differences in adults are unknown, there is evidence that anatomy and posture change considerably during growth and development.
  
  
  METHODS
  One hundred seventy-three young athletes (age range, 9-18 years) were assessed for stage of maturation and placed into 1 of 3 groups, according to Tanners stages 1 and 2 (MatGrp1), 3 and 4 (MatGrp2), and 5 (MatGrp3). Participants were measured for pelvic angle, hip anteversion, quadriceps angle, tibiofemoral angle, femur length, tibial length, genu recurvatum, tibial torsion, navicular drop, general joint laxity, and anterior knee laxity. Data were compared by sex and maturation group.
  
  
  RESULTS
  When comparing maturation groups, limb length, pelvic angle, and tibial torsion increased with maturation, and anterior knee laxity, genu recurvatum, tibiofemoral angle, and foot pronation decreased with maturation. Females had greater general joint laxity, hip anteversion, and tibiofemoral angles, and shorter femur and tibial lengths than males, regardless of maturation group. Maturational changes in knee laxity and quadriceps angles were sex dependent.
  
  
  CONCLUSIONS
  We observed a general change of posture with maturation that began with greater knee valgus, knee recurvatum, and foot pronation in MatGrp1, then moved toward a relative straightening and external rotation of the knee, and supination of the foot in later maturation groups. While the majority of the measures changed similarly in males and females across maturation groups, decreases in quadriceps angles and anterior knee laxity were greater in males compared to females, and females were observed to have a more inwardly rotated hip and valgus knee posture, compared to males, particularly in later maturation groups.
authors.affiliation: Applied Neuromechanics Research Laboratory, Department of Exercise and Sport Science, University of North Carolina at Greensboro, 1408 Walker Ave., Greensboro, NC 27402, USA. sjshultz@uncg.edu
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Shultz
authors.forename: Anh-Dung
authors.initials: AD
authors.lastname: Nguyen
authors.forename: Randy J
authors.initials: RJ
authors.lastname: Schmitz
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D000886:Anthropometry; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000033:anatomy & histology* / Q000254:growth & development / Q000502:physiology*; D008297:Male; D011187:Posture / Q000502:physiology*; D012727:Sex Characteristics; D011795:Surveys and Questionnaires