Stroke commonly results in abnormal muscle synergy, spasticity, muscle weakness and neural couplings. Stroke patients often present with movement deficits with respect to range of motion (ROM), joint coordination, and movement smoothness in the affected arm and hand. Our previous work showed that HandSOME, a spring-powered hand exoskeleton that compensates for flexor tone in the fingers and thumb, improves ROM and function while worn. This study aims to 1) investigate if an independent home therapy program using HandSOME can improve unassisted ROM and functional grasp of the affected hand, and 2) to design a portable and light-weight exoskeleton suitable for home based arm rehabilitation. This dissertation was broken into four components. 1) Individuals with chronic stroke completed a 4-week home intervention using HandSOME. Outcome measures were collected before and after the intervention and in a 3-month follow up. Changes in Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT) were used as primary outcome measures. Kinematic data were also collected to evaluate changes in ROM of the fingers and thumb, and hand movement efficiency (measure of proximal arm control). Seven individuals with chronic stroke completed the home therapy program. Five responded well to the intervention with gains of 6 or more on the ARAT or the FMA. The five responders had significant improvements in hand movement efficiency (p = 0.038). At the 3-month follow up, ROM gains were no longer significant and clinical score improvements were partially lost. 2) While the HandSOME enabled adequate range of motion at the fingers, some subjects had difficulty supinating the forearm enough to properly grasp objects and finger extension ability would degrade as the arm was lifted against gravity. A five-degree-of-freedom (DOF) spring operated movement enhancer for arm rehabilitation (SpringWear) was designed to address these issues. A list of prototypes were fabricated to refine the design. The current version SpringWear 1.0 uses the same spring technology used in HandSOME to provide assistance in three DOFs: forearm supination or pronation, elbow extension, and shoulder elevation.3) A preliminary study was conducted to evaluate SpringWear 1.0 usability when chronic stroke patients perform ROM and functional tasks. Maximum angles in shoulder elevation, forearm supination or pronation, elbow extension and shoulder elevation, are all significantly increased when wearing this device, whereas only ROM in elbow flexion extension is significantly increased (p < 0.001). The initial starting positions of all three assisted joints shifted with assistance, which prevented an increase in ROM even though the maximum joint position increased in all joints. The hand aperture and finger joint angle didn't increase significantly with assistance. However, subjects who were tested with further increased assistance load in shoulder elevation, showed further increased hand aperture and finger joint angles. 4) Currently the development of HandSOME R3 and SpringWear 2.0 is under way. The design of HandSOME R3 focuses on improving the sensor and datalogger technology, and refining the structure. The design of SpringWear 2.0 focuses on incorporating gear systems in ROM measurement, reducing the deformation shoulder elevation mechanism under heavy load.
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