Movement Kinematics of the Ipsilesional Upper Extremity in Persons With Moderate or Mild Stroke

Abstract

Background. An increasing number of studies have indicated that the ipsilesional arm may be impaired after stroke. There is, however, a lack of knowledge whether ipsilesional deficits influence movement performance during purposeful daily tasks. Objective. The aim of this study was to investigate whether, and to what extent, movement impairments are present while performing an ipsilesional upper extremity task during the first 3 months after stroke. Methods. Movement kinematics describing movement time, smoothness, velocity, strategy, and pattern were captured during a standardized drinking task in 40 persons with first-ever stroke and 20 controls. Kinematics were measured early and at 3 months poststroke, and sensorimotor impairment was assessed with Fugl-Meyer Assessment in stroke. Results. Half of the ipsilesional kinematics showed significant deficits early after stroke compared to controls, and the stroke severity had a significant impact on the kinematics. Movements of the ipsilesional arm were slower, less smooth, demonstrated prolonged relative time in deceleration, and increased arm abduction during drinking. Kinematics improved over time and reached a level comparable with controls at 3 months, except for angular velocity of the elbow and deceleration time in reaching for those with more severe motor impairment. Conclusions. This study demonstrates that movements of the ipsilesional arm, during a purposeful daily task, are impaired after stroke. These deficits are more prominent early after stroke and when the motor impairment is more severe. In clinical studies and praxis, the use of less-affected arm as a reference may underestimate the level of impairment and extent of recovery.