The Effectiveness Of Single Joint Hybrid Assistive Limb (HAL-SJ) Robotic Exoskeleton Therapy In Improving Functional Outcomes Among Workers With Wrist Fractures: A Randomized Controlled Trial

The HAL is a hybrid control system that consists of a ‘Cybernic Voluntary Control (Bio-Cybernic Control)’ and ‘Cybernic Autonomous Control (Cybernic Robot Control)’. The cybernic control system can provide suitable physical support to wearers with various conditions including both healthy persons and physically challenged persons by using the two types of algorithms as complementary controls. The Cybernic Voluntary Control provides physical supports/actions according to the operator’s voluntary intention caused by the bioelectrical signals including muscle activity. The power units of HAL generate power assist torque by amplifying the wearer’s own joint torque estimated from his/her bioelectrical signals, and the support motions are consequently controlled. Bioelectrical signals, including myoelectricity, are useful and reliable information to estimate a human’s motion intentions because the signals are measured just before corresponding visible muscle activities. Thus, the wearer receives physical support directly by an unconscious interface using the bioelectrical signals. In contrary, the Cybernic Autonomous Control autonomously provides a desired functional motion generated according to the wearer’s body constitution, conditions, and purposes of motion support During the intervention session, the participant will perform repetitions of different wrist movements such as extension, flexion, supination and pronation whilst assisted by a robot arm which receives feedback from the bioelectrical signals generated by the muscle movement. The researcher is a certified HAL-SJ operator accredited by Cyberdyne Inc. and is competent to conduct the robotic intervention for the intervention group. Participants will be selected based on the inclusion and exclusion criteria. The selected participants will be informed about the study and only be included in the study after giving their informed consent. The intervention group will receive a 60-minutes HAL-SJ robotic therapy session conducted by the researcher daily on a 5-day/week routine basis within two hours after the conventional therapy sessions. Week 1 Intervention Protocol HAL-SJ – Gentle Mode i) Extension: 50 repetitions; 3 sets ii) Flexion: 50 repetitions; 3 set iii) Supination: 50 repetitions; 3 sets iv) Pronation: 50 repetitions; 3 sets Parameters: Assist Gain: 75-100 Assist Level: x1 Flexion/Extension Signal Balance: 100%/100% Active/Relax Phase: 10 seconds/10 seconds Week 2 Intervention Protocol HAL-SJ – Gentle Mode i) Extension: 50 repetitions; 3 sets ii) Flexion: 50 repetitions; 3 sets iii) Supination: 50 repetitions; 3 sets iv) Pronation: 50 repetitions; 3 sets Parameters: Assist Gain: 50-75 Assist Level: x1 Flexion/Extension Signal Balance: 100% : 100% Active/Relax Phase: 10 seconds/10 seconds Week 3 Intervention Protocol HAL-SJ – Gentle Mode i) Extension: 50 repetitions; 3 sets ii) Flexion: 50 repetitions; 3 sets iii) Supination: 50 repetitions; 3 sets iv) Pronation: 50 repetitions; 3 sets Parameters: Assist Gain: 25-50 Assist Level: x1 Flexion/Extension Signal Balance: i) 50% : 100% ii) 100% : 50% Active/Relax Phase: 10 seconds/10 seconds Week 4 Intervention Protocol HAL-SJ – Gentle Mode i) Extension: 50 repetitions; 3 sets ii) Flexion: 50 repetitions; 3 sets iii) Supination: 50 repetitions; 3 sets iv) Pronation: 50 repetitions; 3 sets Parameters: Assist Gain: 0-25 Assist Level: x1 Flexion/Ext Signal Balance: i) 25% : 100% ii) 100% : 25% Active/Relax Phase: 10 seconds/10 seconds