title: Sex differences in total frontal plane knee movement and velocity during a functional single-leg landing.
abstract: OBJECTIVE
  Females land with more knee valgus than males. While most studies have evaluated lower extremity mechanics during double leg landing, most sports require single-leg landing from a double or single leg takeoff. Further, knee movement occurs toward both varus and valgus during functional landing. The purpose of this study was to determine if differences exist between females and males in total frontal plane movement and velocity of the knee during single-leg landing.
  
  
  METHODS
  Experimental cohort.
  
  
  METHODS
  Motion analysis laboratory.
  
  
  METHODS
  Forty healthy, physically-active females (n = 20) and males (n = 20).
  
  
  METHODS
  Three-dimensional motion analysis was completed on the lower extremities during double-leg jumping followed by a single-leg landing. Student's t-tests (p ≤ 0.05) were used to determine if differences exist in frontal plane knee angles (valgus and varus excursion) and angular velocities between females and males.
  
  
  RESULTS
  Females demonstrated greater knee valgus and varus excursion, and valgus and varus velocities compared to males (p < 0.05).
  
  
  CONCLUSIONS
  These findings suggest that total movement in the frontal plane at the knee may be an important factor in injury mechanics in females. Further, single-leg landing from a functional jump should be considered when comparing landing biomechanics between females and males.
authors.affiliation: Department of Physical Therapy, College of Allied Health Sciences East Carolina University, Greenville, NC 27834, USA. Electronic address: jenkinsw@ecu.edu.
authors.forename: Walter L
authors.initials: WL
authors.lastname: Jenkins
authors.affiliation: VCU RUN LAB, Department of Physical Therapy, Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23298, USA. Electronic address: dswilliams@vcu.edu.
authors.forename: D S Blaise
authors.initials: DS
authors.lastname: Williams
authors.affiliation: Nova Medical Center, 1900 Oates Drive, Suite 100, Mesquite, TX 75150, USA. Electronic address: kelseywilliams@nova.com.
authors.forename: Kelsey
authors.initials: K
authors.lastname: Williams
authors.affiliation: Kinetic Physical Therapy and Wellness, 1350-A East Arlington Blvd, Greenville, NC 27858, USA. Electronic address: Joshhefner44@gmail.com.
authors.forename: Josh
authors.initials: J
authors.lastname: Hefner
authors.affiliation: Lenox Baker Children's Hospital, Duke University Health System, 3000 Erwin Road, Durham, NC 27705, USA. Electronic address: Hannah.bendahmane@gmail.com.
authors.forename: Hannah
authors.initials: H
authors.lastname: Welch
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology*; D012727:Sex Characteristics; D016474:Weight-Bearing / Q000502:physiology
keywords: Frontal plane; Knee; Landing; Sex