The KNEEhabilitation Study: Improving Disability in Individuals With Knee Osteoarthritis

Primary outcomes

1. Mean in Self-reported Disability Score as Measured by the Western Ontario and McMasters Universities Index Between Groups

   Time frame: 8-weeks from Baseline

   The Western Ontario and McMasters Universities Index is reliable and valid measure of self reported disability. The physical function consists of 17 items and asks about the magnitude of difficulty when ascending and descending stairs, rising from sitting, standing, bending, walking, getting in / out of a car, shopping, putting on and taking off socks, rising from bed, lying in bed, getting in and out of the bath, sitting, getting on and off the toilet, completing heavy household duties, and completing light household duties. Each item is presented in a 5 point Likert-type format and uses the following descriptors for possible answer choices none, mild moderate, severe, and extreme. Each descriptor corresponds to an ordinal scale of 0-4. The scores are summed for the items in each subscale, with total possible ranges as 0-68. Higher scores on the WOMAC indicate greater amounts of functional limitations.

2. Mean Voluntary Quadriceps Activation as Measured by the Central Activation Ratio Expressed as a Percent of Full Activation

   Time frame: 8-weeks from Baseline

   The investigators assessed voluntary quadriceps central activation ratio as a representative variable of lower extremity neuromuscular activation using the supra imposition technique. Quadriceps central activation ratio has been demonstrated to be significantly decreased in knee osteoarthritis (OA) compared to healthy, matched controls, and the investigators have reported acceptable measurement reliability (ICC2,k = 0.85)

3. Mean Maximal Quadriceps Strength as Measured by the Maximal Isometric Voluntary Contractions Normalized to Body Weight

   Time frame: 8-weeks from Baseline

   Quadriceps strength was measured in Newton Meters normalized to body weight of the individuals. Strength was assessed in 90 degrees of knee flexion.

4. Mean Internal Knee Extension Moment During Walking Gait Measured in Nm/ Body Weight*m

   Time frame: 8-weeks from Baseline

   The peak internal knee extension moment was calculated using using inverse dynamics calculations in the first 50% of the stance phase of gait and normalized to the Body Weight* height (m) of the individual during self selected gait speed.

5. Mean Knee Flexion Angle During Walking Gait Measured in Degrees of Knee Flexion

   Time frame: 8-weeks from Baseline

   The peak Knee Flexion Angle was calculated using using inverse dynamics calculations in the first 50% of the stance phase of gait and during self selected gait speed.