Posture evaluation and rehabilitation in persons with Parkinson’s Disease using wearable sensors

Parkinson's disease (PD) is a multi-systemic neurodegenerative disorder that affects the human nervous system, the hallmark is the decline of dopaminergic neurons in the midbrain’s substantia nigra. It is a progressive neurodegenerative syndrome affecting movement, gait and cognitive function. The clinical assessment of PD is based on rating scales like MDS-UPDRS. Nowadays, wearable sensors are used in the clinic to monitor mobility, providing qualitative and quantitative measures of motor impairment and disease progression. Also, wearable sensors are used in rehabilitation, assessing gait and posture to give biofeedback to the user on motor performance. The thesis focuses on assessing postural instability in people affected by PD and developing a biofeedback rehabilitation system to correct postural problems (e.g., Pisa syndrome) using wearable sensors. In terms of postural assessment, data acquired during the quiet standing (performed before and after levodopa intake) using a single wearable inertial sensor worn on the lower back have been analysed. Regarding rehabilitation, a biofeedback system has been developed for posture rehabilitation in Parkinsonian patients with Pisa syndrome and camptocormia. To develop a system that can be used for both clinical and home-based rehabilitation, an algorithm was developed and validated to identify the tilt angles adopted by the subject during static training. Specifically, the identified angles are related to trunk flexion and lateral bending, typical of subjects with postural issues. The developed rehabilitation system consists of a single sensor placed on the opposite shoulder to the involuntary inclination. It provides vibrotactile feedback if the patient performs trunk flexion or lateral bending. Finally, the prototype system was tested by three subjects who evaluated it using a questionnaire, providing useful feedback on comfort, usability, and possible training rehabilitation programs.