Towards an objective assessment of motor function in sub-acute stroke patients: Relationship between clinical rating scales and instrumental gait stability indexes.

The assessment of walking function alterations is a key issue to design effective rehabilitative interventions in sub-acute stroke patients. Nevertheless, the objective quantification of these alterations remains a challenge. Clinical rating scales are commonly used in clinical practice, but have been proven prone to errors associated to the evaluator subjective perception. On the other hand, instrumental measurement of trunk acceleration can be exploited for an objective quantitative characterization of gait function, but it is not applied in routine clinical practice, because the resulting quantitative indexes have not been related to the clinically information, conventionally provided by the rating scales. To overcome this limitation, the relationship between the indexes, in specific clinical conditions, and rating scale must be better investigated, to support their exploitability in the clinical practice as a fast and reliable screening tool. Thirty-one sub-acute stroke patients (17 with and 14 without cane) participated in the study. All were assessed with 6 rating scales (MI, TCT, MRI, FAC, WHS, CIRS) and 2 functional tests (2MWT and TUG). Sample Entropy (SEN) and Recurrence Quantification Analysis (RQA) in AP, ML and V directions were calculated over 2MWT and walking section of TUG. The influence of assessment task and cane was analysed, as well as correlation of SEN and RQA indexes with clinical rating scales. SEN and RQA on the medio-lateral plane resulted influenced by the use of the cane, while the correlations between indexes and clinical scales showed that SEN and RQA for antero-posterior direction correlate positively with WHS.

Upper limb evaluation with robotic exoskeleton. Normative values for indices of accuracy, speed and smoothness.

BACKGROUND: Robotic rehabilitation devices for upper limb function (ULF) provide global indicators of a patient's ability, but the temporal evolution of motion related to motor control is disregarded. OBJECTIVE: To determine normative values for indices of accuracy, speed and smoothness in the evaluation of upper limb function. METHODS: Twenty-five healthy individuals performed the Armeo®Spring device "Vertical Capture" task. Custom stand-alone software was developed to provide the following indices: global Hand Path Ratio (HPR), local HPR in the target area (locHPR), vertical and horizontal overshoot (vertOS, horOS), maximum and mean velocity (maxVel, meanVel), mean/maximum velocity, number of peaks in velocity profiles (NVelPeaks) and normalized jerk (NormJerk). The dependence of indices on task characteristics was analyzed by an ANCOVA test. Indices inner relationships were assessed by a correlation and a factor analysis. Normative values were then provided. RESULTS: 4,268 single reaching movements were analyzed. Four indices were not affected by movement direction. Indices were minimally influenced by the difficulty level. Based upon correlation and factor analysis indices and can be grouped into three assessment fields, dealing with precision, velocity and smoothness. CONCLUSIONS: We have developed a tool to assess ULF in dynamic condition. Normative values were obtained to be used as references in assessing patients.