Abstract
<title>Abstract</title> <p>Background Recovery after stroke is characterised by substantial inter-individual variability and can differ across impairment domains. Current knowledge of upper-extremity (UE) recovery is largely based on unilateral motor assessments. However, most activities of daily living (ADLs) require bilateral UE use. Moreover, proprioceptive impairments may follow distinct recovery trajectories compared with motor deficits and could influence the recovery of bilateral capacity. This study aimed to characterize and compare the recovery of different sensorimotor impairments during the subacute phase, using unilateral, bilateral, and proprioceptive robotic tasks. Methods Participants (n = 41) were assessed using the KINARM Exoskeleton Lab at three time points: admission to inpatient rehabilitation, prior to discharge, and six months post-stroke. Participants performed a unilateral task (Visually Guided Reaching), a bilateral task (Ball on Bar), and a proprioceptive task (Arm Position Matching), as well as a clinical assessment of performance in ADLs (CAHAI). For each robotic task, a Z-score based on normative data was calculated. Linear mixed models were used to assessed changes over time and associations between assessments. Results Improvement was observed in all robotic assessments (p ≤ 0.01), with most of the improvement occurring during the rehabilitation period. Recovery trajectories across tasks followed different patterns in 40% to 53% of participants, with the largest differences observed between motor and proprioceptive tasks. Linear mixed models indicated a significant between-subject effect across all tasks, whereas a significant within-subject effect was only observed between unilateral and bilateral tasks, indicating independent recovery trajectories between motor and proprioceptive domains. Unilateral capacity, bilateral capacity, and proprioception were all independent contributors to ADL performance, with bilateral capacity showing the strongest contribution.</p>