University of Twente Student Theses

Login

Quantification of simulated pathological synergies in stroke patients using a multisensory system based on inertial sensing and sEMG

Getrouw, J.S.D. (2019) Quantification of simulated pathological synergies in stroke patients using a multisensory system based on inertial sensing and sEMG.

[img] PDF
13MB
Abstract:Introduction. The Fugl-Meyer assessment is a valid and reliable clinical assessment for determining the stage of recovery in patients with stroke. The examiner quantifies the corresponding impairment for each item by means of a score (0, 1 or 2 per item). The lowest score is assigned when the voluntary movement task cannot be executed; the median score is assigned when the task is partly executed, while the maximum score is assigned when the task is fully executed. However, the assigned score depends on experimenter’s subjective judgement and can vary depending on individual opinions. Moreover, consistent estimations of the joint angles and information concerning electromyographic (EMG) activity of the muscles are not provided by the Fugl-Meyer assessment, so that the exact underlying pathophysiological mechanisms that form the basis of limb synergies are still unclear. Research questions. 1. What is the optimal set of sensor-to-segment calibration movements performed by the subjects? 2. Which clinically relevant insights related to stroke patients can the multisensory system provide? Methods. Healthy subjects were instructed to perform a set of twenty-six calibration movements so that the multisensory system could estimate the joint angles during the movements. Based on the variance accounted for (VAF) and the mutual angles between pairs of calibration movements, the optimal set of calibration movements is investigated. After the calibration procedure, the subjects were instructed to perform movements within synergies, mixing synergies, and out of synergies based on the Fugl-Meyer Assessment for the upper extremity (FMA-UE). The subjects were instructed to perform these movements without the limitations caused by the flexor synergy (pathologically unaffected), and then with the limitations caused by the flexor synergy (pathologically affected). The system was tested on detecting clinically relevant differences in joint angles and muscle activities between unimpaired and simulated pathologically affected movements. These differences were statistically tested by means of the Wilcoxon signed rank test with a significance level of 5%. Findings. Overall, the system could detect statistically significant differences in the joint angles regarding shoulder abduction, shoulder flexion, elbow flexion, and forearm pronation and/or supination. Moreover, a significant decrease in agonistic and antagonistic muscle activity during pathologically affected movements could be detected by the system. However, a significant difference in coactivation between selected muscles during pathologically unaffected and simulated pathologically affected movements could not be detected. Conclusion: The optimal set of sensor-to-segment calibration movements include a static pose of the ulnar side of the hand, repeated forearm pronation or supination, a static pose on the left side of the thumb, a static pose of the forearm aligned in the direction of gravity with the elbow fully extended, repeated elbow flexion with the forearm pronated, repeated shoulder flexion with the elbow flexed, repeated trunk flexion, and repeated ipsilateral and contralateral trunk rotation. The influence of the flexor synergy caused limitations in joint angles due to insufficient activity of the agonist muscles.
Item Type:Essay (Master)
Faculty:EEMCS: Electrical Engineering, Mathematics and Computer Science
Subject:53 electrotechnology
Programme:Electrical Engineering MSc (60353)
Link to this item:http://purl.utwente.nl/essays/79829
Export this item as:BibTeX
EndNote
HTML Citation
Reference Manager

 

Repository Staff Only: item control page