title: Can two-dimensional video analysis during single-leg drop vertical jumps help identify non-contact knee injury risk? A one-year prospective study.
abstract: BACKGROUND
  Previous studies showed that the amount of hip flexion and the combination of knee valgus and lateral trunk motion, measured with two-dimensional video analysis, were related to three-dimensional measured knee joint moments during single-leg drop vertical jumps, but it remains unclear whether these measurements can be used to identify non-contact knee injury risk.
  
  
  METHODS
  Fifty injury-free female athletes participated in the study. Two-dimensional video analysis was used to measure hip flexion, knee valgus and lateral trunk motion angles during single-leg drop vertical jumps. Time loss non-contact knee injuries were registered during a one-year follow-up. Independent t-tests and receiver operating characteristic analysis were used to analyze the predictive ability of the two-dimensional angles.
  
  
  RESULTS
  Seven participants sustained a time loss non-contact knee injury. Hip flexion was not significantly different between groups (P>.05). The combination of knee valgus and lateral trunk motion was significantly smaller in the injured (P=.036) and non-injured legs (P=.009) of the future injured group compared with the respective matched leg of the non-injured group. The receiver operating characteristic analysis showed a significant discriminative accuracy between groups for the combination of knee valgus and lateral trunk motion of the uninjured leg of the future injured group with the matched leg of the non-injured group (area under curve=0.803; P=.012).
  
  
  CONCLUSIONS
  The measurement of a combination of increased knee valgus and ipsilateral trunk motion during the single-leg drop vertical jump with two-dimensional video analysis can be used to help identify female athletes with increased non-contact knee injury risk.
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101 b1501, 3001 Heverlee, 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, Tervuursevest 101 b1501, 3001 Heverlee, Belgium. Electronic address: bart.malfait@faber.kuleuven.be.
authors.forename: Bart
authors.initials: B
authors.lastname: Malfait
authors.affiliation: Division of Orthopedics and Traumatology, Department of Development and Regeneration, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. Electronic address: stefaan.nijs@uzleuven.be.
authors.forename: Stefaan
authors.initials: S
authors.lastname: Nijs
authors.affiliation: Physical Medicine and Rehabilitation, University Hospitals Leuven, Campus Pellenberg, Weligerveld 1, 3212 Pellenberg, Belgium. Electronic address: koen.peers@uzleuven.be.
authors.forename: Koen H E
authors.initials: KH
authors.lastname: Peers
authors.affiliation: Physical Medicine and Rehabilitation, University Hospitals Leuven, Campus Pellenberg, Weligerveld 1, 3212 Pellenberg, Belgium. Electronic address: stijn.vereecken@uzleuven.be.
authors.forename: Styn
authors.initials: S
authors.lastname: Vereecken
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101 b1501, 3001 Heverlee, 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, Tervuursevest 101 b1501, 3001 Heverlee, Belgium. Electronic address: filip.staes@faber.kuleuven.be.
authors.forename: Filip F
authors.initials: FF
authors.lastname: Staes
mesh_terms: D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D056352:Athletes; D001265:Athletic Injuries / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007717:Knee / Q000503:physiopathology*; D007718:Knee Injuries / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology*; D007866:Leg; D009038:Motion; D011446:Prospective Studies; D012372:ROC Curve; D016059:Range of Motion, Articular; D018570:Risk Assessment; D013177:Sports; D014741:Video Recording; D055815:Young Adult
keywords: Female athletes; Injury prevention; Knee injury; Screening; Two-dimensional video analysis