Kinematic measures for upper limb motor assessment during robot-mediated training in patients with severe sub-acute stroke

Purpose: Kinematic assessments are increasingly used as motor outcome measures during upper limb robot-assisted training, in addition to clinical scales. However, their relevance has not been evaluated much. Methods: Thirty-eight patients with severe sub-acute stroke (age 56 +/- 17 [19-87] years; time since stroke, 55 +/- 22 days) carried out 16 sessions (average 3/week, 35 +/- 15 days) of upper limb robot-assisted training combined with standard therapy. Pre/post motor performance was evaluated using the Fugl-Meyer Assessment scale, Motor Status Scale (MSS) and kinematic measures. Motor outcomes were compared and relationships between clinical and kinematic outcomes were analyzed. Results: All clinical and kinematic outcomes improved after training (p < 0.01). FM score increased from 17.7 +/- 10.0 to 28.6 +/- 15.4. All baseline kinematic measures were strongly correlated with clinical scores. Correlations between clinical and kinematic changes were moderate (r = -0.65 for change in FM Proximal score and change in accuracy measure). However, smoothness and accuracy indicators were shown to be responsive measures. Conclusion: This study demonstrated that baseline kinematic measures and their pre/post training changes were significantly correlated with clinical motor outcome measures. However, even if kinematic measures are valid for the evaluation of motor impairment we cannot propose to substitute common clinical measures of motor function which also evaluate functional abilities of the upper limb.