Abstract
This study examined the treatment efficacy of proximal-emphasized robotic rehabilitation by using the InMotion ARM (P-IMT) versus distal-emphasized robotic rehabilitation by using the InMotion WRIST (D-IMT) in patients with stroke. A total of 40 patients with stroke completed the study. They received P-IMT, D-IMT, or control treatment (CT) for 20 training sessions. Primary outcomes were the Fugl-Meyer Assessment (FMA) and Medical Research Council (MRC) scale. Secondary outcomes were the Motor Activity Log (MAL) and wrist-worn accelerometers. The differences on the distal FMA, total MRC, distal MRC, and MAL quality of movement scores among the 3 groups were statistically significant (P = 0.02 to 0.05). Post hoc comparisons revealed that the D-IMT group significantly improved more than the P-IMT group on the total MRC and distal MRC. Furthermore, the distal FMA and distal MRC improved more in the D-IMT group than in the CT group. Our findings suggest that distal upper-limb robotic rehabilitation using the InMotion WRIST system had superior effects on distal muscle strength. Further research based on a larger sample is needed to confirm long-term treatment effects of proximal versus distal upper-limb robotic rehabilitation.
Introduction
Most stroke survivors are burdened with significant physical dysfunction, and approximately 60% to 80% continue to have upper-limb (UL) motor deficits into the chronic phase of stroke that have a large effect on their daily life1,2. Developing effective rehabilitation interventions to maxmize UL motor recovery and functional independence of patients with stroke is therefore one of the top priorities in clinical practice and research3,4.
Robot-assisted therapy (RT) has emerged during the last decade as a novel rehabilitation approach to intensify UL motor function5,6,7,8. RT helps provide intensive, repetitive, and interactive training in a controlled environment to promote motor control and recovery of patients9,10,11,12,13,14. Although positive results of RT on motor outcomes have been noted13,14,15, there are disparate effects and heterogeneities between trials depending on the robotic types (eg, exoskeleton versus end-effector, or proximal versus distal approach), protocols, dosages, and problems of patients15,16.
Very few studies have directly compared the relative effects of different robotic devices. A recent systematic review15 investigated the effect of robotic types and reported a trend favoring end-effector rather than exoskeleton robotic devices on motor function. However, the superiority of treatment effect on the UL joints targeted by robotics remains unknown, especially for distal robotics15. Thus, comparative trials of different robotic types (eg, proximal versus distal robots) are warranted to tailor robot-aided UL rehabilitation to patient’s needs.
This study mainly compared the treatment effects of the InMotion ARM versus the InMotion WRIST robotic systems. The major difference between the 2 robotic devices is that the InMotion ARM focuses on training shoulder and elbow movements (ie, proximal UL), and the InMotion WRIST targets wrist and forearm movements (ie, distal UL). The proximal UL segments are critical for stability and transport of the arm, and the distal UL joints are mainly responsible for object manipulation and are important for performing daily activities17,18.
Motor control of the proximal UL and distal UL might be driven by different descending pathways19. The dorsolateral pathways (eg, corticospinal and rubrospinal tracts) are important for control of distal UL movements, and the ventromedial pathways (eg, reticulospinal, vestibulospinal, and tectospinal tracts) act more on the axial and proximal UL muscles and movements20,21. Although the neural bases act on proximal and distal UL segments and their functional roles appear to be different, direct comparisons of the clinical efficacy of proximal versus distal UL training in stroke patients are lacking.
Mazzeloni et al.22 used the same robotic systems to evaluate the treatment effects of proximal RT versus distal RT and proximal RT combined in 2 groups. However, the study goals of Mazzeloni et al. and this work are different. The effects of RT directly related to the UL segments specifically treated could not be drawn from the study findings of Mazzeloni et al. The 2 RT systems, InMotion ARM and InMotion WRIST, allow us to directly compare the outcomes affected by the proximal versus distal UL training.
In addition, recent reviews of RT have shown non-significant improvements or small effects on daily function after UL robotic rehabilitation in patients with stroke14,15,23. Major goals of stroke rehabilitation are to improve not only motor function but also functional performance on daily activities. Moreover, many patients were unable to translate the improvements of motor function and muscle strength to daily activity performance, which led to persistent functional dependence24. Therefore, this study provided functional task practice after RT to enhance the gains from proximal and distal UL robotic rehabilitation on motor function and muscle strength transfer into the patients’ daily functional performance.
The study purposes were to investigate the treatment effects of proximal-emphasized RT by using the InMotion ARM (P-IMT) versus distal-emphasized RT by using the InMotion WRIST (D-IMT) compared with a control treatment (CT) in patients with stroke. We designed a conventional rehabilitation program as the CT to provide a higher-level of clinical evidence, which decreased the influence of nondirective research environment and participant factors on treatment efficacy (eg, the Hawthorne effect), and to pose a more ethical approach instead of no treatment or placebo.[…]
TBI Rehabilitation 