Directionally Specific Objective Postural Response Assessment Tool for Treatment Evaluation in Stroke Patients

The aim of the research is to develop an objective evaluation tool for use in stroke rehabilitation clinical practice. Stroke patients are prone to particularly high risk of fall, which may differ for various directions of movement. An apparatus enabling perturbations and postural response assessment in eight directions in transversal plane during standing was used to assess data in seven neurologically intact volunteers and 10 stroke patients before and after the rehabilitation. Ground reaction force and center of pressure were acquired during the perturbation, signal processed and compared to Berg Balance Scale (BBS), a clinical outcome measure of balance. The results of the weight load ratio between the affected and unaffected lower extremity demonstrated objective positive outcomes of the rehabilitation and also correlated with the clinical instrument BBS. Additionally, the center of pressure ratio between the anterior/posterior and medial/lateral peak for each perturbation direction have shown identifiable postural response strategies in selected directions of transverse plane. The directional postural information can be helpful when identifying and evaluating the objective rehabilitation progress which can lead to application of targeted rehabilitation techniques. The directional indicator also demonstrated correlation with the BBS in directions indicating rehabilitation progress. When considering the common use with the clinical instrument, the proposed objective rehabilitation progress evaluation tool may also become helpful in directional fall risk indication. The proposed tool may become a powerful instrument, when the balance training and postural response assessment will move to remote or home environment as a telerehabilitation service.