Characterization of stroke-related upper limb motor impairments across various upper limb activities by use of kinematic core set measures

Abstract

Background: Upper limb kinematic assessments provide quantifiable information on qualitative movement behavior and limitations after stroke. A comprehensive characterization of spatiotemporal kinematics of stroke subjects during upper limb daily living activities is lacking. Herein, kinematic expressions were investigated with respect to different movement types and impairment levels for the entire task as well as for motion subphases.

Method: Chronic stroke subjects with upper limb movement impairments and healthy subjects performed a set of daily living activities including gesture and grasp movements. Kinematic measures of trunk displacement, shoulder flexion/extension, shoulder abduction/adduction, elbow flexion/extension, forearm pronation/supination, wrist flexion/extension, movement time, hand peak velocity, number of velocity peaks (NVP), and spectral arc length (SPARC) were extracted for the whole movement as well as the subphases of reaching distally and proximally. The effects of the factors gesture versus grasp movements, and the impairment level on the kinematics of the whole task were tested. Similarities considering the metrics expressions and relations were investigated for the subphases of reaching proximally and distally between tasks and subgroups.

Results: Data of 26 stroke and 5 healthy subjects were included. Gesture and grasp movements were differently expressed across subjects. Gestures were performed with larger shoulder motions besides higher peak velocity. Grasp movements were expressed by larger trunk, forearm, and wrist motions. Trunk displacement, movement time, and NVP increased and shoulder flexion/extension decreased significantly with increased impairment level. Across tasks, phases of reaching distally were comparable in terms of trunk displacement, shoulder motions and peak velocity, while reaching proximally showed comparable expressions in trunk motions. Consistent metric relations during reaching distally were found between shoulder flexion/extension, elbow flexion/extension, peak velocity, and between movement time, NVP, and SPARC. Reaching proximally revealed reproducible correlations between forearm pronation/supination and wrist flexion/extension, movement time and NVP.

Conclusion: Spatiotemporal differences between gestures versus grasp movements and between different impairment levels were confirmed. The consistencies of metric expressions during movement subphases across tasks can be useful for linking kinematic assessment standards and daily living measures in future research and performing task and study comparisons.

Trial registration: ClinicalTrials.gov Identifier NCT03135093. Registered 26 April 2017, https://clinicaltrials.gov/ct2/show/NCT03135093 .

Keywords: Biomechanical phenomena; Kinematics; Stroke; Upper extremity.

Fig. 1

Experimental protocol of 20 activities of daily life. The task items T1–T10 include intransitive gesture movements without object contact. The task items T11–T20 represent transitive grasping movements with objects contact and manipulation. Tasks that were included in the subphase analysis of reaching distally are encircled in blue and those that include reaching proximally are encircled in green

Fig. 2

Upper limb sensor set-up. The location of the wearable sensors on predefined body segments is shown in relation to the global frame

Fig. 3

Feature-based movement phase segmentation for one subject and a single trial. One trial of the drinking task is presented by dimensionless plotting of the hand IMU position and velocity signals. The red lines indicate the threshold detection of velocity in x-direction. The blue dashed line refers to threshold detection of velocity in z-direction

Fig. 4

Effects of the task and impairment group on core set kinematics. Abd/Add abduction/adduction, Flex/Ext flexion/extension, Pro/Sup pronation/supination, Mov movement, SPARC spectral arc length, TrunkDisp trunk displacement, Vel velocity. *Indicates significant effects between the no, mild, and/or moderate impairment group for both gesture and grasp movements

Fig. 5

A Kinematic metrics during reaching distally per task across subjects (N = 31). The metric expressions are presented in boxplots per task. The vertical black line in each subplot separates the grasp movement tasks on the left side and gesture movement tasks on the right side. Statistically significant comparable metrics across tasks are indicated by asterisks and the bold notation of the gesture or grasping task caption. El-Flex/Ext elbow flexion/extension, FA-Pro/Sup forearm pronation/supination, Mov Time movement time, No of Vel Peak number of peak velocity, Sh-Abd/Add shoulder abduction/adduction, Sh-Flex/Ext shoulder flexion/extension, SPARC spectral arc length, TrunkDisp trunk displacement, Wr-Flex/Ext wrist flexion/extension. B Kinematic metrics during reaching proximally per task across subjects (N = 31). The metric expressions are presented in boxplots per task. The vertical black line in each subplot separates the grasp movement tasks on the left side and gesture movement tasks on the right side. Statistically significant comparable metrics across tasks are indicated by asterisks and the bold notation of the gesture or grasping task caption. El-Flex/Ext elbow flexion/extension, FA-Pro/Sup forearm pronation/supination, Mov Time movement time, No of Vel Peak number of peak velocity, Sh-Abd/Add shoulder abduction/adduction, Sh-Flex/Ext shoulder flexion/extension, SPARC spectral arc length, TrunkDisp trunk displacement, Wr-Flex/Ext wrist flexion/extension

Fig. 5

A Kinematic metrics during reaching distally per task across subjects (N = 31). The metric expressions are presented in boxplots per task. The vertical black line in each subplot separates the grasp movement tasks on the left side and gesture movement tasks on the right side. Statistically significant comparable metrics across tasks are indicated by asterisks and the bold notation of the gesture or grasping task caption. El-Flex/Ext elbow flexion/extension, FA-Pro/Sup forearm pronation/supination, Mov Time movement time, No of Vel Peak number of peak velocity, Sh-Abd/Add shoulder abduction/adduction, Sh-Flex/Ext shoulder flexion/extension, SPARC spectral arc length, TrunkDisp trunk displacement, Wr-Flex/Ext wrist flexion/extension. B Kinematic metrics during reaching proximally per task across subjects (N = 31). The metric expressions are presented in boxplots per task. The vertical black line in each subplot separates the grasp movement tasks on the left side and gesture movement tasks on the right side. Statistically significant comparable metrics across tasks are indicated by asterisks and the bold notation of the gesture or grasping task caption. El-Flex/Ext elbow flexion/extension, FA-Pro/Sup forearm pronation/supination, Mov Time movement time, No of Vel Peak number of peak velocity, Sh-Abd/Add shoulder abduction/adduction, Sh-Flex/Ext shoulder flexion/extension, SPARC spectral arc length, TrunkDisp trunk displacement, Wr-Flex/Ext wrist flexion/extension

Fig. 6

A Relationship between kinematics of reaching distally across subjects. Core set kinematics of reaching distally are correlated with each other per movement task and impairment level subgroups. 1, Trunk displacement; 2, Shoulder flexion/extension; 3, Shoulder abduction/adduction; 4, Elbow flexion/extension; 5, Forearm pronation/supination; 6, wrist flexion/extension; 7, Movement time; 8, Peak velocity; 9, Number of velocity peaks (NVP); 10, Spectral arc length (SPARC). The correlation coefficient is presented in a color code as shown on the right of each heat map. Strong correlations between metrics that were consistent across tasks are highlighted by black square outlines in the heatmap. The dashed black square outlines represent metric associations, suspected to be consistent across tasks, that were not significantly strong correlated. B Relationship between kinematics of reaching distally across subjects. Core set kinematics of reaching proximally are correlated with each other per movement task and impairment level subgroups. 1, Trunk displacement; 2, Shoulder flexion/extension; 3, Shoulder abduction/adduction; 4, Elbow flexion/extension; 5, Forearm pronation/supination; 6, wrist flexion/extension; 7, Movement time; 8, Peak Velocity; 9, Number of velocity peaks (NVP); 10, Spectral arc length (SPARC). The correlation coefficient is presented in a color code as shown on the right of each heat map. Strong correlations between metrics that were consistent across tasks are highlighted by black square outlines in the heatmap. The dashed black square outlines represent metric associations, suspected to be consistent across tasks, that were not significantly strong correlated

Fig. 6

A Relationship between kinematics of reaching distally across subjects. Core set kinematics of reaching distally are correlated with each other per movement task and impairment level subgroups. 1, Trunk displacement; 2, Shoulder flexion/extension; 3, Shoulder abduction/adduction; 4, Elbow flexion/extension; 5, Forearm pronation/supination; 6, wrist flexion/extension; 7, Movement time; 8, Peak velocity; 9, Number of velocity peaks (NVP); 10, Spectral arc length (SPARC). The correlation coefficient is presented in a color code as shown on the right of each heat map. Strong correlations between metrics that were consistent across tasks are highlighted by black square outlines in the heatmap. The dashed black square outlines represent metric associations, suspected to be consistent across tasks, that were not significantly strong correlated. B Relationship between kinematics of reaching distally across subjects. Core set kinematics of reaching proximally are correlated with each other per movement task and impairment level subgroups. 1, Trunk displacement; 2, Shoulder flexion/extension; 3, Shoulder abduction/adduction; 4, Elbow flexion/extension; 5, Forearm pronation/supination; 6, wrist flexion/extension; 7, Movement time; 8, Peak Velocity; 9, Number of velocity peaks (NVP); 10, Spectral arc length (SPARC). The correlation coefficient is presented in a color code as shown on the right of each heat map. Strong correlations between metrics that were consistent across tasks are highlighted by black square outlines in the heatmap. The dashed black square outlines represent metric associations, suspected to be consistent across tasks, that were not significantly strong correlated