Related Experiment Video
Updated: Jun 23, 2026
Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity
Published on: June 12, 2019
Reliability of elbow stretch reflex assessment in chronic post-stroke hemiparesis
Elizabeth G Condliffe1, David J Clark, Carolynn Patten
1Neural Control of Movement Laboratory, Department of Rehabilitation Sciences, Boston University, Boston, MA, USA.
Objective:
To establish reliability of quantitative measures of elbow joint spastic hypertonia in post-stroke hemiparesis.
Methods:
Nine subjects with post-stroke hemiparesis (mn duration: 42 months) were tested on three separate days. Biceps brachii and brachioradialis EMG were recorded during passive ramp-and-hold extensions applied at seven speeds between 30 and 210 degrees /s. EMG burst duration, onset position threshold, and burst intensity were used to evaluate reflex activity. Torque at 40 degrees of elbow flexion was used as a mechanical indicator of spastic hypertonia.
Results:
Across speeds ICCs were consistent, means ranged between 0.63 and 0.85. Thus, relative reliability was fair to excellent for all parameters. Absolute reliability, determined using standard error of measurement expressed as a percentage of the mean score (%SEM), improved at higher speeds (> or = 120 degrees/s).
Conclusions:
These results establish reliability of reflex and mechanical measures of elbow spastic hypertonia post-stroke. The data demonstrate greater reflex detection at high speeds, indicating greater potential to document meaningful changes in these distinct aspects of spastic hypertonia following intervention.
Significance:
Based on findings of this study, reliability was demonstrated using four parameters of reflex EMG and torque indicating measurement consistency across sessions. These observations motivate determination of requisite effect sizes for clinical trials that evaluate treatment outcome.
