title: Arch structure is associated with unique joint work, relative joint contributions and stiffness during landing.
abstract: To examine lower extremity joint contributions to a landing task in high-(HA) and low-arched (LA) female athletes by quantifying vertical stiffness, joint work and relative joint contributions to landing.
  
  
  METHODS
  Twenty healthy female recreational athletes (10 HA and 10 LA) performed five barefoot drop landings from a height of 30cm. Three-dimensional kinematics (240Hz) and ground reaction forces (960Hz) were recorded simultaneously. Vertical stiffness, joint work values and relative joint work values were calculated using Visual 3D and MatLab.
  
  
  RESULTS
  HA athletes had significantly greater vertical stiffness compared to LA athletes (p=0.013). Though no differences in ankle joint work were observed (p=0.252), HA athletes had smaller magnitudes of knee (p=0.046), hip (p=0.019) and total lower extremity joint work values (p=0.016) compared to LA athletes. HA athletes had greater relative contributions of the ankle (p=0.032) and smaller relative contributions of the hip (p=0.049) compared to LA athletes. No differences in relative contributions of the knee were observed (p=0.255).
  
  
  CONCLUSIONS
  These findings demonstrate that aberrant foot structure is associated with unique contributions of lower extremity joints to load attenuation during landing. These data may provide insight into the unique injury mechanisms associated with arch height in female athletes.
authors.affiliation: Musculoskeletal Analysis Laboratory, Department of Exercise Science, University of Memphis, Memphis, TN, United States. Electronic address: dwp0817@gmail.com.
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Powell
authors.affiliation: Kevin P. Granata Biomechanics Laboratory, Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States.
authors.forename: Robin M
authors.initials: RM
authors.lastname: Queen
authors.affiliation: VCU RUN LAB, Departments of Physical Therapy and Kinesiology & Health Sciences, Virginia Commonwealth University, Richmond, VA, United States.
authors.forename: D S Blaise
authors.initials: DS
authors.lastname: Williams
mesh_terms: D000293:Adolescent; D000843:Ankle Joint / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology*; D005260:Female; D005528:Foot / Q000033:anatomy & histology* / Q000502:physiology*; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D013177:Sports / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology; D055815:Young Adult
keywords: Arch; Foot; Injury; Kinetics; Landing; Work