Improving proprioceptive deficits after stroke through robot-assisted training of the upper limb: a pilot case report study

The Role of Sensory Impairments on Recovery and Rehabilitation After Stroke

PURPOSE OF REVIEW

The current review aims to address critical gaps in the field of stroke rehabilitation related to sensory impairment. Here, we examine the role and importance of sensation throughout recovery of neural injury, potential clinical and experimental approaches for improving sensory function, and mechanism-based theories that may facilitate the design of sensory-based approaches for the rehabilitation of somatosensation.

RECENT FINDINGS

Recently, the field of neurorehabilitation has shifted to using more quantitative and sensitive measures to more accurately capture sensory function in stroke and other neurological populations. These approaches have laid the groundwork for understanding how sensory impairments impact overall function after stroke. However, there is less consensus on which interventions are effective for remediating sensory function, with approaches that vary from clinical re-training, robotics, and sensory stimulation interventions. Current evidence has found that sensory and motor systems are interdependent, but commonly have independent recovery trajectories after stroke. Therefore, it is imperative to assess somatosensory function in order to guide rehabilitation outcomes and trajectory. Overall, considerable work in the field still remains, as there is limited evidence for purported mechanisms of sensory recovery, promising early-stage work that focuses on sensory training, and a considerable evidence-practice gap related to clinical sensory rehabilitation.

Physiotherapy management focusing on proprioceptive impairment in a patient with gait and balance impairments following stroke: A case report

BACKGROUND

Proprioceptive impairment contributes to gait and balance impairments in patients with stroke. Diagnosis functional impairments and evaluation treatment efficacy require quantitative proprioception assessment. However, proprioception assessment has remained limited to ordinal scale measurement, with a lack of ratio scale measurements.

PURPOSE

This case report describes a physiotherapy management program focusing on proprioceptive impairment in patients with stroke using quantitative tests such as Threshold to Detect Passive Motion (TDPM) and Joint Position Sense (JPS).

CASE DESCRIPTION

A63-year-old male patient with an acute pontine lacunar infarction was admitted to our hospital. His muscle strength, selective movement, and trunk activity were preserved. However, the Berg Balance Scale (BBS) and Gait Assessment andIntervention Tool (GAIT) score were 42 and 9 points, observing balance impairment and the buckling knee pattern with hip ataxia during gait. Based on these, TDPM and JPS using image capture were performed. In physiotherapeuticdiagnosis, proprioceptive impairments in the hip and knee joints were the primary functional impairments related to balance and gait. To address these proprioceptive impairments, a 13-day treatment protocol incorporating transcutaneous electrical nerve stimulation (intensity: sensory threshold, frequency: 100 Hz) targeting the quadriceps femoris was performed.

OUTCOMES

The patient was discharged after achieving independent ambulation and improvement in BBS (56 points) and GAIT (2 points) scores, exceeding the minimum clinically important difference. Recovery of proprioceptive impairment corresponded withimproved balance and gait ability.

CONCLUSION

Quantitatively evaluating proprioceptive impairments may provide novel rehabilitation for patients with stroke who have proprioceptive impairments and contribute to clinical decision-making.

Interventions for people with perceptual disorders after stroke: the PIONEER scoping review, Cochrane systematic review and priority setting project

Background

Stroke often affects recognition and interpretation of information from our senses, resulting in perceptual disorders. Evidence to inform treatment is unclear.

Objective

To determine the breadth and effectiveness of interventions for stroke-related perceptual disorders and identify priority research questions.

Methods

We undertook a scoping review and then Cochrane systematic review. Definitions, outcome prioritisation, data interpretation and research prioritisation were coproduced with people who had perceptual disorders post stroke and healthcare professionals. We systematically searched electronic databases (including MEDLINE, EMBASE, inception to August 2021) and grey literature. We included studies (any design) of interventions for people with hearing, smell, somatosensation, taste, touch or visual perception disorders following stroke. Abstracts and full texts were independently dual reviewed. Data were tabulated, synthesised narratively and mapped by availability, sense and interventions. Research quality was not evaluated. Our Cochrane review synthesised the randomised controlled trial data, evaluated risk of bias (including randomisation, blinding, reporting) and meta-analysed intervention comparisons (vs. controls or no treatment) using RevMan 5.4. We judged certainty of evidence using grading of recommendations, assessment, development and evaluation. Activities of daily living after treatment was our primary outcome. Extended activities of daily living, quality of life, mental health and psychological well-being perceptual functional and adverse event data were also extracted.

Results

We included 80 studies (n = 893): case studies (36/80) and randomised controlled trials (22/80). No stroke survivor or family stakeholder involvement was reported. Studies addressed visual (42.5%, 34/80), somatosensation (35%, 28/80), auditory (8.7%, 7/80) and tactile (7.5%, 6/80) perceptual disorders; some studies focused on 'mixed perceptual disorders' (6.2%, 5/80 such as taste-smell disorders). We identified 93 pharmacological, non-invasive brain stimulation or rehabilitation (restitution, substitution, compensation or mixed) interventions. Details were limited. Studies commonly measured perceptual (75%, 60/80), motor-sensorimotor (40%, 32/80) activities of daily living (22.5%, 18/80) or sensory function (15%, 12/80) outcomes.

Cochrane systematic review

We included 18 randomised controlled trials (n = 541) addressing tactile (3 randomised controlled trials; n = 70), somatosensory (7 randomised controlled trials; n = 196), visual (7 randomised controlled trials; n = 225) and mixed tactile-somatosensory (1 randomised controlled trial; n = 50) disorders. None addressed hearing, taste or smell disorders. One non-invasive brain stimulation, one compensation, 25 restitution and 4 mixed interventions were described. Risk of bias was low for random sequence generation (13/18), attrition (14/18) and outcome reporting (16/18). Perception was the most commonly measured outcome (11 randomised controlled trials); only 7 randomised controlled trials measured activities of daily living. Limited data provided insufficient evidence to determine the effectiveness of any intervention. Confidence in the evidence was low-very low. Our clinical (n = 4) and lived experience (n = 5) experts contributed throughout the project, coproducing a list of clinical implications and research priorities. Top research priorities included exploring the impact of, assessment of, and interventions for post-stroke perceptual disorders.

Limitations

Results are limited by the small number of studies identified and the small sample sizes, with a high proportion of single-participant studies. There was limited description of the perceptual disorders and intervention(s) evaluated. Few studies measured outcomes relating to functional impacts. There was limited investigation of hearing, smell, taste and touch perception disorders.

Conclusion

Evidence informing interventions for perceptual disorders after stroke is limited for all senses.

Future work

Further research, including high-quality randomised controlled trials, to inform clinical practice are required.

Study registration

This study is registered as PROSPERO CRD42019160270.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR128829) and is published in full in Health Technology Assessment; Vol. 28, No. 69. See the NIHR Funding and Awards Website for further award information.

System Framework of Robotics in Upper Limb Rehabilitation on Poststroke Motor Recovery

Neurological impairments such as stroke cause damage to the functional mobility of survivors and affect their ability to perform activities of daily living. Recently, robotic treatment for upper limb stroke rehabilitation has received significant attention because it can provide high-intensity and repetitive movement therapy. In this review, the current status of upper limb rehabilitation robots is explored. Firstly, an overview of mechanical design of robotics for upper-limb rehabilitation and clinical effects of part robots are provided. Then, the comparisons of human-machine interactions, control strategies, driving modes, and training modes are described. Finally, the development and the possible future directions of the upper limb rehabilitation robot are discussed.

Vision of the upper limb fails to compensate for kinesthetic impairments in subacute stroke

Kinesthesia is an essential component of proprioception allowing for perception of movement. Due to neural injury, such as stroke, kinesthesia can be significantly impaired. Throughout neurorehabilitation, clinicians may encourage use of vision to guide limb movement to retrain impaired kinesthesia. However, little evidence exists that vision improves kinesthetic performance after stroke. We examined behavioral and neuroanatomical characteristics of kinesthesia post-stroke to determine if these impairments improve with vision. Stroke subjects (N = 281) performed a robotic kinesthetic matching task (KIN) without and with vision at ∼10 days post-stroke. A robotic exoskeleton moved the stroke-affected arm while subjects mirror-matched the movement with the opposite arm. Performance was compared to 160 controls. Spatial and temporal parameters were used to quantify kinesthetic performance. A Kinesthetic Task Score was calculated to determine overall performance on KIN without and with vision. Acute stroke imaging (N = 236) was collected to determine commonalities in lesion characteristics amongst kinesthetic impairment groups. Forty-eight percent (N = 135) of subjects had post-stroke impairment in kinesthesia both without and with vision. Only 19% (N = 52) improved to control-level performance with vision. Of the 48% of subjects that failed to improve with vision, many (N = 77, 57%) had neglect and/or field deficits. Notably 58 subjects (43%) did not have these deficits and still failed to improve with vision. Subjects who failed to improve with vision often had lesions affecting corticospinal tracts, insula, and parietal cortex, specifically the supramarginal gyrus and inferior parietal lobule. Many individuals could not use vision of the limb to correct for impaired kinesthesia after stroke. Subjects that failed to improve kinesthesia with vision had lesions affecting known sensorimotor integration areas. Our results suggest that integration of spatial information is impaired in many individuals post-stroke, particularly after parietal cortex damage. The result is a disconnect between kinesthetic and visuomotor processing necessary for visual limb guidance.

Robotic Assistance for Upper Limbs May Induce Slight Changes in Motor Modules Compared With Free Movements in Stroke Survivors: A Cluster-Based Muscle Synergy Analysis

Background: The efficacy of robot-assisted rehabilitation as a technique for achieving motor recovery is still being debated. The effects of robotic assistance are generally measured using standard clinical assessments. Few studies have investigated the value of human-centered instrumental analysis, taking the modular organization of the human neuromotor system into account in assessing how stroke survivors interact with robotic set-ups. In this paper, muscle synergy analysis was coupled with clustering procedures to elucidate the effect of human-robot interaction on the spatial and temporal features, and directional tuning of motor modules during robot-assisted movements. Methods: Twenty-two stroke survivors completed a session comprising a series of hand-to-mouth movements with and without robotic assistance. Patients were assessed instrumentally, recording kinematic, and electromyographic data to extract spatial muscle synergies and their temporal components. Patients' spatial synergies were grouped by means of a cluster analysis, matched pairwise across conditions (free and robot-assisted movement), and compared in terms of their spatial and temporal features, and directional tuning, to examine how robotic assistance altered their motor modules. Results: Motor synergies were successfully extracted for all 22 patients in both conditions. Seven clusters (spatial synergies) could describe the original datasets, in both free and robot-assisted movements. Interacting with the robot slightly altered the spatial synergies' features (to a variable extent), as well as their temporal components and directional tuning. Conclusions: Slight differences were identified in the characteristics of spatial synergies, temporal components and directional tuning of the motor modules of stroke survivors engaging in free and robot-assisted movements. Such effects are worth investigating in the framework of a modular description of the neuromusculoskeletal system to shed more light on human-robot interaction, and the effects of robotic assistance and rehabilitation.

Development of a System Architecture for Evaluation and Training of Proprioceptive Deficits of the Upper Limb

Proprioception plays a fundamental role in maintaining posture and executing movement, and the quantitative evaluation of proprioceptive deficits in poststroke patients is important. But currently it is not widely performed due to the complexity of the evaluation tools required for a reliable assessment. The aims of this pilot study were to (a) develop a system architecture for upper limb evaluation and training of proximal and distal sense of position in the horizontal plane and (b) test the system in healthy and pathological subjects. Two robotic devices for evaluation and training of, respectively, wrist flexion/extension and shoulder-elbow manipulation were employed. The system we developed was applied in a group of 12 healthy subjects and 10 patients after stroke. It was able to quantitatively evaluate upper limb sense of position in the horizontal plane thanks to a set of quantitative parameters assessing position estimation errors, variability, and gain. In addition, it was able to distinguish healthy from pathological conditions. The system could thus be a reliable method to detect changes in the sense of position of patients with sensory deficits after stroke and could enable the implementation of novel training approaches for the recovery of normal proprioception.

Elastic Tape Improved Shoulder Joint Position Sense in Chronic Hemiparetic Subjects: A Randomized Sham-Controlled Crossover Study

Background

Elastic tape has been widely used in clinical practice in order to improve upper limb (UL) sensibility. However, there is little evidence that supports this type of intervention in stroke patients.

Objective

To verify the effect of elastic tape, applied to the paretic shoulder, on joint position sense (JPS) during abduction and flexion in subjects with chronic hemiparesis compared to sham tape (non-elastic tape). Furthermore, to verify if this potential effect is correlated to shoulder subluxation measurements and sensorimotor impairment.

Methods

A crossover and sham-controlled study was conducted with post-stroke patients who were randomly allocated into two groups: 1) those who received Sham Tape (ST) first and after one month they received Elastic Tape (ET); 2) those who received Elastic Tape (ET) first and after one month they received Sham Tape (ST). The JPS was evaluated using a dynamometer. The absolute error for shoulder abduction and flexion at 30° and 60° was calculated. Sensorimotor impairment was determined by Fugl-Meyer, and shoulder subluxation was measured using a caliper.

Results

Thirteen hemiparetic subjects (average time since stroke 75.23 months) participated in the study. At baseline (before interventions), the groups were not different for abduction at 30° (p = 0.805; p = 0.951), and 60° (p = 0.509; p = 0.799), or flexion at 30° (p = 0.872; p = 0.897) and 60° (p = 0.853; p = 0.970). For the ET group, differences between pre and post-elastic tape for abduction at 30° (p<0.010) and 60° (p<0.010), and flexion at 30° p<0.010) and 60° (p<0.010) were observed. For the ST group, differences were also observed between pre and post-elastic tape for abduction at 30° (p<0.010) and 60° (p<0.010), and flexion at 30° (p<0.010,) and 60° (p<0.010). Potential effects were only correlated with shoulder subluxation during abduction at 30° (p = 0.001, r = -0.92) and 60° (p = 0.020, r = -0.75).

Conclusion

Elastic tape improved shoulder JPS of subjects with chronic hemiparesis regardless of the level of UL sensorimotor impairment. However, this improvement was influenced by the subluxation degree at abduction.

Neural correlates of motor recovery after robot-assisted stroke rehabilitation: a case series study

Robot-assisted bilateral arm therapy (RBAT) has shown promising results in stroke rehabilitation; however, connectivity mapping of the sensorimotor networks after RBAT remains unclear. We used fMRI before and after RBAT and a dose-matched control intervention (DMCI) to explore the connectivity changes in 6 subacute stroke patients. Sensorimotor functions improved in the RBAT and DMCI groups after treatment. Enhanced activation changes were observed in bilateral primary motor cortex (M1) and bilateral supplementary motor area (SMA) after RBAT. Dynamic causal model analysis revealed that interhemispheric connections were enhanced in RBAT patients. These preliminary findings suggest that intracortical and intercortical coupling might underlie poststroke RBAT.