Article

OBJECTIVE: To evaluate inter- and intrarater reliability of isokinetic muscle
strength measurements during knee extension and flexion in postmenopausal women
with osteopenia. DESIGN: Reliability study assessing inter- and intrarater
reliability. SETTING: General community. PARTICIPANTS: A convenience sample of 27
postmenopausal women (mean age +/- SD, 68.2+/-7.3y) with defined osteopenia from
a bone mineral density T score of less than 1.5 and a wrist fracture within the
last 2 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Isokinetic
concentric muscle strength during knee extension and flexion was measured for 2
test conditions: 5 repetitions at 60 degrees /s, and 25 repetitions at 180
degrees /s. Agreement between tests was evaluated with the intraclass correlation
coefficient (ICC(2,1)). Mean difference between tests, standard error of
measurement (SEM and SEM%), and smallest real difference (SRD and SRD%) were
calculated with 95% confidence intervals. SRD% and SEM% are emphasized in the
results to allow congruent comparisons between the different test conditions.
RESULTS: ICC(2,1) reflected high agreement both for inter- and intrarater
reliability, with most of the values .90 or greater. There were no significant
differences between the left and the right leg at any of the 3 tests. Some
differences were apparent between the test sessions, but these were not
systematic. Agreements were overall higher for assessments during knee extension
than knee flexion. The SEM% was between 3.5% and 10.2% for knee extension, and
7.0% and 17.7% for knee flexion. SRD% was suggested to be between 15% and 20% for
knee extension, and 25% and 30% for knee flexion. CONCLUSIONS: Isokinetic
assessments of thigh muscle strength in postmenopausal women with osteopenia are
of high reliability, with a level of agreement comparable to the levels found in
previous reliability studies concerning both the healthy elderly and elderly with
different health conditions. The measurement errors are small to moderate. The
established SRD% provides thresholds for whether observed changes in strength in
this patient group represent true change, which allows evaluations of minimal
clinical importance in future studies.
CI - Copyright (c) 2012 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS