Sensor Fusion to Infer Locations of Standing and Reaching Within the Home in Incomplete Spinal Cord Injury.

OBJECTIVE: The objective of rehabilitation after spinal cord injury is to enable successful function in everyday life and independence at home. Clinical tests can assess whether patients are able to execute functional movements but are limited in assessing such information at home. A prototype system is developed that detects stand-to-reach activities, a movement with important functional implications, at multiple locations within a mock kitchen. DESIGN: Ten individuals with incomplete spinal cord injuries performed a sequence of standing and reaching tasks. The system monitored their movements by combining two sources of information: a triaxial accelerometer, placed on the subject's thigh, detected sitting or standing, and a network of radio frequency tags, wirelessly connected to a wrist-worn device, detected reaching at three locations. A threshold-based algorithm detected execution of the combined tasks and accuracy was measured by the number of correctly identified events. RESULTS: The system was shown to have an average accuracy of 98% for inferring when individuals performed stand-to-reach activities at each tag location within the same room. CONCLUSIONS: The combination of accelerometry and tags yielded accurate assessments of functional stand-to-reach activities within a home environment. Optimization of this technology could simplify patient compliance and allow clinicians to assess functional home activities.

Benefits of Using a Voice and EMG-Driven Actuated Glove to Support Occupational Therapy for Stroke Survivors.

Many mechatronic devices exist to facilitate hand rehabilitation, however few directly address deficits in muscle activation patterns while also enabling functional task practice. We developed an innovative voice and electromyography-driven actuated (VAEDA) glove, which is sufficiently flexible/portable for incorporation into hand-focused therapy post-stroke. The therapeutic benefits of this device were examined in a longitudinal intervention study. Twenty-two participants with chronic, moderate hand impairment [Chedoke-McMaster Stroke Assessment Stage of Hand (CMSA-H = 4)] enrolled > 8 months post-stroke for 18 1-h training sessions ( 3 × week) employing a novel hand-focused occupational therapy paradigm, either with (VAEDA) or without (No-VAEDA) actuated assistance. Outcome measures included CMSA-H, Wolf Motor Function Test (WMFT), Action Research Arm Test, Fugl-Meyer Upper Extremity Motor Assessment (FMUE), grip and pinch strength and hand kinematics. All outcomes were recorded at baseline and endpoint (immediately after and four weeks post-training). Significant improvement was observed following training for some measures for the VAEDA group (n = 11) but for none of the measures for the No-VAEDA group (n = 11). Specifically, statistically significant gains were observed for CMSA-H (p = 0.038) and WMFT (p = 0.012) as well as maximum digit aperture subset (p = 0.003, n = 7), but not for the FMUE or grip or pinch strengths. In conclusion, therapy effectiveness appeared to be increased by employment of the VAEDA glove, which directly targets deficits in muscle activation patterns.

Use of a Portable Assistive Glove to Facilitate Rehabilitation in Stroke Survivors With Severe Hand Impairment.

Treatment options for stroke survivors with severe hand impairment are limited. Active task practice can be restricted by difficulty in voluntarily activating finger muscles and interference from involuntary muscle excitation. We developed a portable, actuated glove-orthosis, which could be employed to address both issues. We hypothesized that combining passive cyclical stretching (reducing motoneuronal hyperexcitability) imposed by the device with active-assisted, task-oriented training (rehabilitating muscle activation) would improve upper extremity motor control and task performance post-stroke. Thirteen participants who experienced a stroke 2-6 months prior to enrollment completed 15 treatment sessions over five weeks. Each session involved cyclically stretching the long finger flexors (30 min) followed by active-assisted task-oriented movement practice (60 min). Outcome measures were completed at six intervals: three before and three after treatment initiation. Overall improvement in post-training scores was observed across all outcome measures, including the Graded Wolf Motor Function Test, Action Research Arm Test, and grip and pinch strength (p ≤ 0.02), except finger extension force. No significant change in spasticity was observed. Improvement in upper extremity capabilities is achievable for stroke survivors even with severe hand impairment through a novel intervention combining passive cyclical stretching and active-assisted task practice, a paradigm which could be readily incorporated into the clinic.

Use of an electromyographically driven hand orthosis for training after stroke.

A pilot study was conducted to test the feasibility of using electromyographic signals to drive an active orthosis for hand therapy after stroke. Five stroke survivors with chronic hemiparesis completed 18 one-hour training sessions over 6 weeks. Activation patterns of a long finger flexor muscle and a long finger extensor muscle controlled an orthosis, the J-Glove, which provided assistance to finger extension to facilitate grasp-and-release movements. Initial results showed improvement in performance on one component, lifting a can, of the Wolf Motor Function Test for every subject and on the Action Research Arm Test for three of the subjects. Excitingly, a couple of the subjects showed signs of improved muscle activation patterns, although this requires further investigation.