title: The effect of pelvic position on popliteal angle achieved during 90:90 hamstring-length test.
abstract: BACKGROUND
  Hamstring muscle length is commonly measured because of its perceived relationship to injury of both the hamstrings themselves and the pelvis and lumbar spine. The popliteal (knee-extension) angle measured from the starting position hip and knee at 90° is a commonly used indirect measure of hamstring muscle length. When this measure has been undertaken in the literature previously, little attention was paid to the position of the pelvis, which may significantly influence measurements taken.
  
  
  METHODS
  Repeated-measures.
  
  
  METHODS
  University human performance laboratory.
  
  
  METHODS
  60 healthy physically active males (mean age 20.1 ± 1.8 y, range 18-24 y).
  
  
  METHODS
  The 2 extremes of pelvic position (anterior and posterior).
  
  
  METHODS
  Popliteal angle (with maximal knee extension) was measured in 2 positions, 1 of full anterior and 1 of full posterior pelvic tilt.
  
  
  RESULTS
  The mean difference in popliteal angle between anterior to posterior pelvic positions was 13.4° ± 9° (range 0-26°); this was statistically significant (P = .0001).
  
  
  CONCLUSIONS
  The findings of the study indicate that pelvic position has a significant effect on popliteal angle and therefore should be taken into account when measuring hamstring muscle length.
authors.affiliation: Faculty of Sport, Exercise and Physiotherapy, University of Salford, Manchester, UK.
authors.forename: Lee
authors.initials: L
authors.lastname: Herrington
mesh_terms: D000293:Adolescent; D000328:Adult; D006615:Hip / Q000502:physiology; D006801:Humans; D007717:Knee / Q000502:physiology; D008161:Lumbosacral Region / Q000502:physiology; D008297:Male; D009068:Movement / Q000502:physiology; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D010388:Pelvis / Q000033:anatomy & histology; D016683:Supine Position; D013848:Thigh; D055815:Young Adult