Associations between frontal plane joint stiffness and proprioceptive acuity in knee osteoarthritis

Arthritis Care & Research , 04/27/2012

Cammarata ML et al. – While both joint stiffness and proprioception were reduced in the osteoarthritis (OA) population, they were only weakly correlated. This suggests that other neurophysiologic factors play a larger role in the proprioceptive deficits in knee OA.


  • Participants were 13 patients with knee OA and 14 healthy age–matched subjects.
  • Proprioceptive acuity was assessed in varus and valgus using the threshold to detection of passive movement (TDPM) test.
  • Passive joint stiffness was estimated as the slope of the normalized torque–angle relationship at 0° joint rotation (neutral) and several rotations in varus and valgus.
  • Analyses of variance were performed to determine the effect of OA and sex on each metric.
  • Linear regression was used to assess the correlation between the TDPM and joint stiffness.


  • The TDPM was significantly higher (P < 0.05) in the OA group compared to the control group for both varus and valgus, but significant sex differences were observed.
  • Passive joint stiffness was significantly reduced (P < 0.05) in OA participants compared to the control group in neutral and valgus, but not varus, and significantly reduced in women compared to men.
  • A weak negative correlation was observed between the TDPM and stiffness estimates, suggesting that poorer proprioception was associated with less joint stiffness.

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