title: Effect of lower limb malalignment in the frontal plane on transverse plane mechanics during gait in young individuals with varus knee alignment.
abstract: BACKGROUND
  Varus knee alignment has been identified as a risk factor for the progression of medial knee osteoarthritis (OA). This study tested the hypothesis that not only frontal plane kinematics and kinetics but also transverse plane lower extremity mechanics during gait are affected by varus malalignment of the knee.
  
  
  METHODS
  Eighteen, otherwise healthy children and adolescents with varus malalignment of the knee were studied to examine the association between static varus malalignment and functional gait parameters. Kinematic data were collected using a Vicon motion capture system (Vicon Motion Systems, Oxford, UK). Two AMTI force plates (Advanced Mechanical Technology, Inc., Watertown, MA, USA) were used to collect kinetic data.
  
  
  RESULTS
  The results indicated that changes in transverse plane mechanics occur concomitantly with changes in knee malalignment in the frontal plane. A mechanical consequence of varus knee malalignment is obviously an increased endorotation of the foot (internal foot placement) and an increased internal knee rotation (tibia rotation) during stance phase. The linear correlation between the maximum external knee adduction moment in terminal stance and the internal knee rotation in terminal stance (r=0.823, p<0.001) shows that this transverse plane gait mechanics is directly in conjunction with intrinsic compressive load on the medial compartment during gait.
  
  
  CONCLUSIONS
  Understanding factors that influence dynamic knee joint loading in healthy, varus malaligned knees may help us to identify risk factors that lead to OA. Thus, three-dimensional gait analysis could be used for clinical prognoses regarding the onset or progression of medial knee OA.
authors.affiliation: Orthopedic University Hospital Friedrichsheim gGmbH, Frankfurt/Main, Germany. Electronic address: felix.stief@gmx.de.
authors.forename: Felix
authors.initials: F
authors.lastname: Stief
authors.affiliation: Orthopedic Hospital for Children, Aschau i. Chiemgau, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Böhm
authors.affiliation: Orthopedic Hospital for Children, Aschau i. Chiemgau, Germany.
authors.forename: Chakravarthy U
authors.initials: CU
authors.lastname: Dussa
authors.affiliation: Orthopedic Hospital for Children, Aschau i. Chiemgau, Germany.
authors.forename: Christel
authors.initials: C
authors.lastname: Multerer
authors.affiliation: Department of Biomechanics in Sport, Technical University, Munich, Germany.
authors.forename: Ansgar
authors.initials: A
authors.lastname: Schwirtz
authors.affiliation: Department of Orthopedic Sports Medicine, Technical University, Munich, Germany.
authors.forename: Andreas B
authors.initials: AB
authors.lastname: Imhoff
authors.affiliation: Orthopedic Hospital for Children, Aschau i. Chiemgau, Germany.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Döderlein
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena / Q000502:physiology; D017760:Bone Malalignment / Q000503:physiopathology*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005528:Foot / Q000503:physiopathology*; D005684:Gait / Q000502:physiology*; D006621:Hip Joint / Q000503:physiopathology*; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D012399:Rotation; D055815:Young Adult
keywords: Gait analysis; Internal tibia rotation; Knee adduction moment; Knee osteoarthritis; Varus malalignment