Affiliations: [a] Department of Physical Medicine and Rehabilitation,
Başkent University, Ankara, Turkey | [b] Department of Physical Therapy and Rehabilitation,
Baskent University, Ankara, Turkey
Abstract: We aimed to determine the test-retest reproducibility of isokinetic
dynamometric measurement of the resistance to passive motion for quantitative
evaluation of wrist flexor spasticity in stroke patients. In a repeated
measures design, 2 raters tested each subject 3 times on 6 separate days.
Twenty one sub-acute/chronic stroke patients 55 ± 14.1
years of age with an average disease duration of 7.04 ±
2.87 months volunteered to take part along with 20 age-matched healthy
controls. Clinical assessment of spasticity was performed using an Ashworth
Scale. Resistance measurements of 5 consecutive flexion/extension movements of
the wrists were performed at 3 reselected angular velocities
(10°/s, 30°/s, 45°/s), using a computerized dynamometer, set in the
continuous passive joint motion mode. The maximum peak torque values in for
each subject were calculated for each set of repetitions. The reproducibility
of strength measurements were evaluated using single-measure and
average-measure intra class correlation coefficients (ICCs). There was a
significant positive correlation between Ashworth Scale and torque values.
Torque values were significantly higher in groups with patients who had strokes
than in the control group. The dynamometric scores were positively correlated
with Ashworth Scale grades. The ICCs for intra-tester measurements were high
and ranged 0.82–0.87. The Bland-Altman plots indicated no systematic bias. The
standard error of measurement (SEM) ranged 0.27–0.38 Nm while the smallest
real difference (SRD) ranged −1.0 Nm to 1.1 Nm). These
values correspond to a mean SEM% of 31% and SRD% of 85%. These
values indicate relatively large measurement error and thus does not support
the use of isokinetic dynamometry, using this protocol and measurement system,
in assessing wrist muscles spasticity in stroke patients.
