title: Analysis of knee flexion characteristics and how they alter with the onset of knee osteoarthritis: a case control study.
abstract: BACKGROUND
  The purpose of this study was to examine the differences in gait profile between patients with knee osteoarthritis (OA) and healthy control and to create motion characteristics that will differentiate between them.
  
  
  METHODS
  Twenty three patients diagnosed with knee OA and 21 healthy matched controls underwent a gait test using a sensor system (gaitWALK). Gait parameters evaluated were: stride duration, knee flexion range of motion (ROM) in swing and stance. T-Test was used to evaluate significant differences between groups (P < 0.05).
  
  
  RESULTS
  Patients with knee OA had significant lower knee flexion ROM (10.3° ± 4.0°) during stance than matched controls (18.0° ± 4.0°) (p < 0.001). Patients with knee OA had significant lower knee flexion ROM (54.8° ± 5.5°) during swing than matched controls (61.2° ± 6.1) (p = 0.003). Patients with knee OA also had longer stride duration (1.12 s ± 0.09 s) than matched controls (1.06 s ± 0.11 s), but this was not statistically significant (p = 0.073). Motion characteristics differentiate between a patient with knee OA and a healthy one with a sensitivity of 0.952 and a specificity of 0.783.
  
  
  CONCLUSIONS
  Significant differences were found in the gait profile of patients with knee OA compared to matched control and motion characteristics were identified. This test might help clinicians identify and evaluate a knee problem in a simple gait test.
authors.affiliation: Royal National Orthopaedic Hospital, Stanmore, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: McCarthy
authors.forename: Diana
authors.initials: D
authors.lastname: Hodgins
authors.forename: Amit
authors.initials: A
authors.lastname: Mor
authors.forename: Avi
authors.initials: A
authors.lastname: Elbaz
authors.forename: Ganit
authors.initials: G
authors.lastname: Segal
mesh_terms: D000368:Aged; D053587:Arthrometry, Articular / Q000379:methods*; D001696:Biomechanical Phenomena; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D005684:Gait; D006801:Humans; D007557:Israel / Q000453:epidemiology; D007719:Knee Joint / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D020370:Osteoarthritis, Knee / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*