Testing robot-based assist-as-needed therapy for improving active participation of a patient during early neurorehabilitation: a case study

Abstract

In this study, a patient in the Intensive Care-Unit received robot-based mobilization therapy with an assist-as-needed (AAN) function over the course of three weeks. Therapists were able to adapt the hip range of motion $\beta$, the bed verticalization angle $\alpha$ and the leg load force F <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Load</inf> for each therapy, based on the current condition of the patient. To evaluate the patient active participation, surface electromyography (sEMG) of the M. rectus femoris (RF) and M. biceps femoris (BF) were measured and analyzed. It was observed that the patient active participation, measured through sEMG, increased along with increased hip range of motion $\beta$, bed verticalization angle $\alpha$ and leg load force F <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Load</inf> set by the therapists. The patient muscle activation pattern followed the pattern of healthy controls, in part. To the authors’ best knowledge, this study is the first of its kind to be performed with an ICU patient.