Development and Validation of Customizable, Adaptive SPring-Actuated Hand EXoskeleton (CASPHEX) Designed for...

Area of Science:

• Rehabilitation Engineering
• Biomechanics
• Neurorehabilitation

Background:

• Passive hand devices offer home-based therapy for stroke survivors but have limited functionality.
• Current devices struggle to address intrinsic muscle impairments or adapt to user intent.
• Active robotic systems often face challenges with complexity and safety for home use.

Purpose of the Study:

• To develop and evaluate a novel hand exoskeleton, Customizable, Adaptive Spring-actuated Hand Exoskeleton (CASPHEX), for targeted and adaptive rehabilitation.
• To design a control algorithm enabling CASPHEX to counteract flexor hypertonia and adapt to user intent for grasping and opening movements.
• To assess the efficacy of CASPHEX in improving hand function and range of motion in both healthy subjects and stroke survivors.

Main Methods:

• CASPHEX was developed with customizable, adaptive spring actuation and a novel control algorithm for intent detection and hypertonia management.
• Initial validation involved 5 healthy subjects to measure response times during actuated joint movements.
• Clinical testing with 11 stroke survivors assessed voluntary control and functional task performance.

Main Results:

• CASPHEX demonstrated response times of 615±53 ms (proximal) and 577±47 ms (distal) in healthy subjects.
• Stroke survivors using CASPHEX showed significant improvements in finger extension range of motion.
• Participants using CASPHEX also exhibited significant improvements in Box and Block Test scores.

Conclusions:

• CASPHEX shows potential as an effective tool for impairment-specific, home-based robot-assisted hand therapy for stroke survivors.
• The device's adaptive assistance and user intent detection overcome limitations of current passive hand rehabilitation devices.
• CASPHEX facilitates functional task performance and improves key clinical outcome measures in stroke survivors.