title: Experimental muscle pain during a forward lunge--the effects on knee joint dynamics and electromyographic activity.
abstract: OBJECTIVE
  The purpose of this study was to investigate whether the knee joint dynamics during a forward lunge could be modulated by experimentally induced vastus medialis pain in healthy subjects.
  
  
  METHODS
  Randomised cross-over study.
  
  
  METHODS
  Biomechanical movement laboratory.
  
  
  METHODS
  20 healthy subjects were included. One subject was excluded during data collection.
  
  
  METHODS
  The subjects performed forward lunges before, during and 20 minutes after induction of experimental quadriceps muscle pain. Muscle pain was induced using hypertonic saline (5.8%) injected intramuscularly. Isotonic saline (0.9%) was used as control.
  
  
  METHODS
  Three-dimensional movement analyses were performed and inverse dynamics were used to calculate joint kinematics and kinetics for ankle, knee and hip joints. Electromyographic (EMG) signals of the hamstrings and quadriceps muscles were recorded.
  
  
  RESULTS
  During and after pain, significant decreases in knee joint dynamics and EMG recordings were observed.
  
  
  CONCLUSIONS
  The study shows that local pain in the quadriceps is capable of modulating movements with high knee joint dynamics. The results may have implications in the management of muscle pain and prevention of injuries during activities involving the knee joint.
authors: Clinical Motor Function Laboratory, The Parker Institute, Frederiksberg Hospital, Ndr. Fasanvej 57, DK-2000 Frederiksberg, Denmark. marius.henriksen@frh.regionh.dk
authors: M
authors: M
authors: Henriksen
authors: T
authors: T
authors: Alkjaer
authors: E B
authors: EB
authors: Simonsen
authors: H
authors: H
authors: Bliddal
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D018592:Cross-Over Studies; D004576:Electromyography; D005260:Female; D006801:Humans; D007552:Isotonic Solutions / Q000009:adverse effects; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology*; D009135:Muscular Diseases / Q000503:physiopathology*; D010146:Pain / Q000503:physiopathology*; D052097:Quadriceps Muscle / Q000502:physiology*; D012462:Saline Solution, Hypertonic / Q000009:adverse effects
chemical_list: D007552:Isotonic Solutions; D012462:Saline Solution, Hypertonic