Upper extremity kinematics of a 3D reach-to-grasp-to-mouth task in sub-acute stroke survivors in comparison with healthy controls

Background: Only 5-20% of stroke survivors exhibit almost complete motor recovery at six months post-stroke. The Stroke Recovery and Rehabilitation Roundtable (SRRR) Taskforce has recommended the use of performance assays that predict recovery. However, not much is known about the differences across various stroke severity groups. The purpose of this study was to determine whether kinematic parameters of time, average velocity, shoulder angles and elbow angles were able to distinguish upper extremity movement capacity in individuals with varying levels of stroke severity and healthy controls. Methods: : This is a cross-sectional study, which is part of a large cohort study. 27 sub-acute stroke survivors (58.8 ± 12.7 years; 18 males, 9 females; categorized into mild (51-66), moderate (25-50) and severe (<25) Fugl Meyer Assessment of Upper Extremity (FM-UE) categories and 10 healthy controls (48.9 ± 13.7 years; 6 males, 4 females) performed 20 trials of a 3D reach-to-grasp-to-mouth task. Kinematic parameters were analyzed using a one-way ANOVA test. Results: : Movement time was significantly different between severe and all other stroke groups (mild [p<0.001], moderate [p<0.001]) and healthy controls (p<0.001). Average velocity was significantly different between all three stroke groups (mild [p=0.03], moderate [p<0.001], severe [d= -3.7, p<0.001]) and healthy controls. Elbow flexion was significantly different between moderate and severe stroke groups (p=0.009). Elbow extension showed significant differences between mild and moderate stroke groups (p<0.001). Shoulder extension exhibited significant differences between mild (p<0.001), moderate (p<0.001) and severe (p<0.001) and healthy controls. Conclusions: : Kinematic analysis of a reach-to-grasp-to-mouth task helps to differentiate between varying groups of severity post-stroke such as mild, moderate and severe, based on Fugl Meyer for Upper Extremity scores.