title: Can two-dimensional measured peak sagittal plane excursions during drop vertical jumps help identify three-dimensional measured joint moments?
abstract: BACKGROUND
  Less optimal sagittal plane movement patterns are believed to increase knee injury risk in female athletes. To facilitate clinical screening with a user-friendly method, the purpose of the present study was to examine the temporal relationships between two-dimensional measured sagittal plane kinematics and three-dimensional joint moments during the double-leg drop vertical jump (DVJ) and single-leg DVJ (SLDVJ).
  
  
  METHODS
  Fifty injury-free female athletes were tested. Maximal excursions of hip flexion, knee flexion and ankle dorsiflexion were measured through two-dimensional video analysis. Three-dimensional motion and ground reaction forces were recorded to calculate external hip flexion, knee flexion and knee abduction moments during the entire stance phase of DVJ and SLDVJ. One-dimensional statistical parametric mapping was used to examine relationships between peak two-dimensional kinematic variables and three-dimensional moment profiles.
  
  
  RESULTS
  Hip flexion was significantly related to the hip and knee flexion moment for both tests and knee abduction moment for DVJ during the time frames corresponding with highest three-dimensional moments, while knee flexion was significantly related to the hip flexion moment during these time frames. No significant relationships were found for ankle dorsiflexion with any of the joint moments.
  
  
  CONCLUSIONS
  Two-dimensional measured sagittal plane hip flexion angles at the deepest landing position were associated with peak joint moments of the hip and knee during DVJ and SLDVJ, while the amount of knee flexion was only associated with the hip flexion moment. Assessment of knee injury risk with two-dimensional video analysis could benefit from measuring maximal hip flexion, more so than knee flexion.
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Belgium, Tervuursevest 101 b1501, 3001 Leuven, Belgium. Electronic address: bart.dingenen@faber.kuleuven.be.
authors.forename: Bart
authors.initials: B
authors.lastname: Dingenen
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Belgium, Tervuursevest 101 b1501, 3001 Leuven, Belgium. Electronic address: bart.malfait@faber.kuleuven.be.
authors.forename: Bart
authors.initials: B
authors.lastname: Malfait
authors.affiliation: Research Institute for Sport and Exercise Sciences, Faculty of Science, Liverpool John Moores University, Liverpool, UK, Tom Reilly Building, Byrom Street Campus, Liverpool L3 3AF, UK. Electronic address: j.vanrenterghem@ljmu.ac.uk.
authors.forename: Jos
authors.initials: J
authors.lastname: Vanrenterghem
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Belgium, Tervuursevest 101 b1501, 3001 Leuven, Belgium. Electronic address: m.a.robinson@ljmu.ac.uk.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Robinson
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Belgium, Tervuursevest 101 b1501, 3001 Leuven, Belgium. Electronic address: sabine.verschueren@faber.kuleuven.be.
authors.forename: Sabine M P
authors.initials: SM
authors.lastname: Verschueren
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Belgium, Tervuursevest 101 b1501, 3001 Leuven, Belgium. Electronic address: filip.staes@faber.kuleuven.be.
authors.forename: Filip F
authors.initials: FF
authors.lastname: Staes
mesh_terms: D000293:Adolescent; D056352:Athletes; D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology / Q000517:prevention & control*; D007719:Knee Joint / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D014741:Video Recording / Q000379:methods; D055815:Young Adult
keywords: Female athletes; Knee injury; Screening; Two-dimensional video analysis