Longitudinal evaluation of upper extremity reachable workspace in ALS by Kinect sensor

Area of Science:

• Neurology
• Biomedical Engineering
• Rehabilitation Medicine

Background:

• Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease impacting motor neurons.
• Functional decline in upper extremities is a significant challenge for ALS patients.
• Objective and sensitive outcome measures are crucial for tracking disease progression and therapeutic efficacy in ALS.

Purpose of the Study:

• To evaluate longitudinal changes in upper extremity reachable workspace relative surface area (RSA) using Microsoft Kinect in ALS patients.
• To compare RSA changes with established ALS functional scales (ALSFRS-R, ALSFRS-R upper extremity sub-scale) and pulmonary function (FVC).
• To assess the potential of RSA as a novel clinical endpoint for ALS research.

Main Methods:

• Ten patients with ALS underwent assessments over one year using a Microsoft Kinect 3D depth sensor to measure reachable workspace RSA.
• Data collected included RSA, ALSFRS-R, ALSFRS-R upper extremity sub-scale, and Forced Vital Capacity (FVC).
• Linear mixed models were employed to analyze longitudinal changes in these parameters.

Main Results:

• A significant decline of approximately 19% in upper lateral quadrant RSA was observed over one year (p < 0.01).
• No significant changes were noted in other RSA quadrants or total RSA during the study period.
• Concurrently, the ALSFRS-R upper extremity sub-scale significantly worsened by 25% (p < 0.01).

Conclusions:

• Upper extremity reachable workspace RSA, measured by Microsoft Kinect, objectively quantifies functional decline in ALS patients.
• RSA provides more granular insights into upper extremity changes compared to existing ALS outcome measures.
• RSA demonstrates potential as a sensitive clinical endpoint for evaluating upper extremity-targeted therapies in ALS.