Article

OBJECTIVE: To determine whether a decrease in muscle strength over 3 years is
associated with an increase in activity limitations in persons with early
symptomatic knee osteoarthritis (OA), and to examine whether the longitudinal
association between muscle strength and activity limitations is moderated by knee
joint proprioception and laxity. DESIGN: A longitudinal cohort study with 3-year
follow-up. Measurements were performed at the second (t0) and fifth (t1) year of
the Cohort Hip and Cohort Knee (CHECK) study. Statistical analyses included
paired t tests, chi-square tests, and regression analyses. In regression
analyses, the association between muscle strength and activity limitations was
adjusted for confounders. SETTING: A rehabilitation and rheumatology center.
PARTICIPANTS: Subjects (N=146) with early symptomatic knee OA from the CHECK
study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Muscle strength,
proprioception, and laxity were assessed using specifically designed measurement
devices. Self-reported and performance-based activity limitations were measured
with the Western Ontario and McMaster Universities Osteoarthritis Index, the Get
Up and Go test, the walk test, and the stair-climb test. RESULTS: A total of 116
women (79.5%) and 30 men (20.5%), with a mean age +/- SD of 58.4+/-4.9 years and
a mean body mass index +/- SD of 25.5+/-3.6, were included in the study. Overall,
small 3-year changes in muscle strength and activity limitations were observed.
At the group level, the average muscle strength increased by 10% (1.0+/-0.3 to
1.1+/-0.3Nm/kg) over the 3 years. The 3-year decrease in muscle strength was
independently associated with an increase in performance-based activity
limitations on all 3 measures (B=-1.12, B=-5.83, and B=-1.25, respectively).
Proprioception and laxity did not moderate this association. CONCLUSIONS: In
patients with early knee OA, decreased muscle strength is associated with an
increase in activity limitations. Our results are a step toward understanding the
role of muscle weakness in the development of activity limitations in knee OA.
Further well-designed experimental studies are indicated to establish the causal
role of muscle weakness in activity limitations.
CI - Copyright (c) 2014 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS