Kinematic analysis of the upper extremity after stroke - how far have we reached and what have we grasped?

Background: Consequences of stroke frequently comprise reduced movement ability of the upper extremity (UE) and subsequent long-term disability. Clinical scales are used to monitor and evaluate rehabilitation but are often insufficient, while technological advances in 3D motion capture provide detailed kinematics to more objectively quantify and interpret movement deficits. Objectives: To provide a comprehensive overview of research using kinematic movement analysis of the UE in individuals post-stroke with focus on objectives, methodology and findings while highlighting clinical implications and future directions. Major Findings: A literature search yielded 93 studies categorised into four groups: comparative (healthy, stroke, task condition), intervention (clinical trials), methodological and longitudinal. The majority of studies used optoelectronic systems, investigated discrete reaching and involved mainly individuals with moderate or mild stroke impairment in chronic stage. About 80% of the studies were published after year 2004. Speed-related variables were most frequently addressed followed by smoothness indicators, joint angles and trunk displacement. Movements in the hemiparetic side are generally slower, less smooth and show a compensatory movement pattern. Task specificity is crucial for kinematic outcomes. Tables summarising the main characteristics, objectives and results of all included studies are provided. Conclusions: There is still a lack of studies addressing reliability and responsiveness and involving more complex, everyday UE tasks with ecological validity. To facilitate the use of UE kinematic movement analysis in clinics, a research-based simpler data handling with pre-defined output for the results, as commonly used in gait analysis, is warranted.