A robot-aided visuomotor wrist training induces gains in proprioceptive and movement accuracy in the contralateral wrist

The Effect of Proprioceptive Training on Hand Function and Activity Limitation After Open Carpal Tunnel Release Surgery: A Randomized Controlled Study

OBJECTIVE

To investigate the effect of proprioceptive training on hand function and activity limitation in patients undergoing open carpal tunnel release surgery.

DESIGN

Randomized controlled study.

SETTING

A university hospital.

PARTICIPANTS

Thirty patients were included in the study and randomized to proprioceptive training (PT) and conventional rehabilitation (CR) groups.

INTERVENTION

One week after surgery, both groups received CR for 6 weeks. All participants were asked to perform home-based exercises daily in 3 sets with 10 repetitions. For the PT group, a 6-step PT program was conducted starting from Week 6. Both groups received face-to-face interventions twice a week for 12 weeks.

MAIN OUTCOME MEASURES

The outcome measures included the Purdue Pegboard Test (PPT), the joint position sense test (JPST), the Boston Carpal Tunnel Questionnaire, and the Patient-Specific Functional Scale. In total, 3 assessments were performed (at 1, 6 and 12 weeks postoperatively).

RESULTS

In the PT group, the results for PPT were statistically significant (P<.05). Although there was a greater decrease in the absolute angular error value (JPST) of the PT group compared to the CR group, the difference was nonsignificant (P>.05). Similar reductions in activity limitation were seen in both groups (PT: 176%, CR: 175%). Symptom severity decreased by 40% in the PT group vs 32% in the CR group. The effect sizes were larger for the changes between the second and third assessments in the PT group compared to the CR group in all parameters tested.

CONCLUSION

When applied after carpal tunnel release surgery, PT may potentially to improve hand functions, reduce activity limitation, increase participation in activities of daily living, and thus improve quality of life.

A robot-aided visuomotor wrist training induces motor and proprioceptive learning that transfers to the untrained ipsilateral elbow

BACKGROUND

Learning of a visuomotor task not only leads to changes in motor performance but also improves proprioceptive function of the trained joint/limb system. Such sensorimotor learning may show intra-joint transfer that is observable at a previously untrained degrees of freedom of the trained joint.

OBJECTIVE

Here, we examined if and to what extent such learning transfers to neighboring joints of the same limb and whether such transfer is observable in the motor as well as in the proprioceptive domain. Documenting such intra-limb transfer of sensorimotor learning holds promise for the neurorehabilitation of an impaired joint by training the neighboring joints.

METHODS

Using a robotic exoskeleton, 15 healthy young adults (18-35 years) underwent a visuomotor training that required them to make continuous, increasingly precise, small amplitude wrist movements. Wrist and elbow position sense just-noticeable-difference (JND) thresholds and spatial movement accuracy error (MAE) at wrist and elbow in an untrained pointing task were assessed before and immediately after, as well as 24 h after training.

RESULTS

First, all participants showed evidence of proprioceptive and motor learning in both trained and untrained joints. The mean JND threshold decreased significantly by 30% in trained wrist (M: 1.26° to 0.88°) and by 35% in untrained elbow (M: 1.96° to 1.28°). Second, mean MAE in untrained pointing task reduced by 20% in trained wrist and the untrained elbow. Third, after 24 h the gains in proprioceptive learning persisted at both joints, while transferred motor learning gains had decayed to such extent that they were no longer significant at the group level.

CONCLUSION

Our findings document that a one-time sensorimotor training induces rapid learning gains in proprioceptive acuity and untrained sensorimotor performance at the practiced joint. Importantly, these gains transfer almost fully to the neighboring, proximal joint/limb system.

A Systematic Review of the Learning Dynamics of Proprioception Training: Specificity, Acquisition, Retention, and Transfer

OBJECTIVE

We aimed to identify key aspects of the learning dynamics of proprioception training including: 1) specificity to the training type, 2) acquisition of proprioceptive skills, 3) retention of learning effects, and 4) transfer to different proprioceptive skills.

METHODS

We performed a systematic literature search using the database (MEDLINE, EMBASE, Cochrane Library, and PEDro). The inclusion criteria required adult participants who underwent any training program that could enhance proprioceptive function, and at least 1 quantitative assessment of proprioception before and after the intervention. We analyzed within-group changes to quantify the effectiveness of an intervention.

RESULTS

In total, 106 studies with 343 participant-outcome groups were included. Proprioception-specific training resulted in large effect sizes with a mean improvement of 23.4 to 42.6%, nonspecific training resulted in medium effect sizes with 12.3 to 22% improvement, and no training resulted in small effect sizes with 5.0 to 8.9% improvement. Single-session training exhibited significant proprioceptive improvement immediately (10 studies). For training interventions with a midway evaluation (4 studies), trained groups improved by approximately 70% of their final value at the midway point. Proprioceptive improvements were largely maintained at a delayed follow-up of at least 1 week (12 studies). Finally, improvements in 1 assessment were significantly correlated with improvements in another assessment (10 studies).

CONCLUSIONS

Proprioceptive learning appears to exhibit several features similar to motor learning, including specificity to the training type, 2 time constant learning curves, good retention, and improvements that are correlated between different assessments, suggesting a possible, common mechanism for the transfer of training.

Tactile Sensation Improves Following Motor Rehabilitation for Chronic Stroke: The VIGoROUS Randomized Controlled Trial

Background. Up to 85% of people with chronic stroke experience somatosensory impairment, which contributes to poor sensorimotor control and non-use of the affected limb. Neurophysiological mechanisms suggest motor rehabilitation may improve tactile sense post-stroke, however, somatosensory recovery has rarely been reported in controlled trials. Objective. To compare the effect of four upper limb motor rehabilitation programs on the recovery of tactile sensation in adults with chronic stroke. Methods. Adults with chronic stroke and mild or moderate upper extremity hemiparesis (n = 167) were enrolled in a multi-site randomized controlled trial. Participants completed three weeks of gaming therapy, gaming therapy with additional telerehabilition, Constraint-Induced Movement therapy, or traditional rehabilitation. Here, we report the results of a secondary outcome, tactile sensation, measured with monofilaments, before and after treatment, and 6 months later. Results. A mixed-effects general linear model revealed similar positive change in tactile sensitivity regardless of the type of training. On average, participants were able to detect a stimulus that was 32% and 33% less after training and at 6-month follow-up, respectively. One-third of participants experienced recategorization of their level of somatosensory impairment (e.g., regained protective sensation) following training. Poorer tactile sensation at baseline was associated with greater change. Conclusions. About one-third of individuals with mild/moderate chronic hemiparesis experience sustained improvements in tactile sensation following motor rehabilitation, regardless of the extent of tactile input in the rehabilitation program. Potential for sensory improvement is an additional motivator for those post-stroke. Characteristics of those who improve and mechanisms of improvement are important future questions. Clinicaltrials.gov NCT02631850.

The Effectiveness of Proprioceptive Training for Improving Motor Performance and Motor Dysfunction: A Systematic Review

Objective

Proprioceptive training is any intervention aiming to improve proprioceptive function with the ultimate goal to enhance motor function and performance. It has been promoted as an approach to enhance athletic performance and as a tool for sensorimotor rehabilitation. Numerous studies sought to provide evidence on the effectiveness of the approach. However, many different training regimes claiming to train proprioception report a variety of sensorimotor measures that are not directly comparable. This, in turn, makes it difficult to assess effectiveness across approaches. It is the objective of this study to systematically review recent empirical evidence to gain an understanding of which outcome measures are most sensitive, which populations may benefit most from proprioceptive training, and what are the effects on proprioceptive and motor systems.

Methods

Four major databases were searched. The following inclusion criteria were applied: (1) A quantified pre- and post-treatment measure of proprioceptive function. (2) An intervention or training program believed to influence or enhance proprioceptive function. (3) Contained at least one form of treatment or outcome measure that is indicative of somatosensory function and not confounded by information from other sensory modalities. 4) The study reported of at least one quantified measure of motor performance.

Results

Of the 3,297 articles identified by the database search, 70 studies met the inclusion criteria and were included for further review. Across studies, proprioceptive training led to comparable gains in both proprioceptive (+46%) and motor performance (+45%). The majority of studies (50/70) applied active movement interventions. Interventions applying somatosensory stimulation were most successful in clinical populations. Joint position sense error (JPSE) was the most commonly used proprioceptive measure and presents a reliable and feasible measure for clinical use.

Conclusion

Proprioceptive training can lead to significant improvements in proprioceptive and motor function across a range healthy and clinical populations. Regimens requiring active movement of the trainee tended to be most successful in improving sensorimotor performance. Conclusive evidence on how long training gains are retained is still lacking. There is no solid evidence about the underlying long-term neuroplastic changes associated proprioceptive training.

Three-Dimensional Assessment of Upper Limb Proprioception via a Wearable Exoskeleton

Proprioception—the sense of body segment’s position and movement—plays a crucial role in human motor control, integrating the sensory information necessary for the correct execution of daily life activities. Despite scientific evidence recognizes that several neurological diseases hamper proprioceptive encoding with consequent inability to correctly perform movements, proprioceptive assessment in clinical settings is still limited to standard scales. Literature on physiology of upper limb’s proprioception is mainly focused on experimental approaches involving planar setups, while the present work provides a novel paradigm for assessing proprioception during single—and multi-joint matching tasks in a three-dimensional workspace. To such extent, a six-degrees of freedom exoskeleton, ALEx-RS (Arm Light Exoskeleton Rehab Station), was used to evaluate 18 healthy subjects’ abilities in matching proprioceptive targets during combined single and multi-joint arm’s movements: shoulder abduction/adduction, shoulder flexion/extension, and elbow flexion/extension. Results provided evidence that proprioceptive abilities depend on the number of joints simultaneously involved in the task and on their anatomical location, since muscle spindles work along their preferred direction, modulating the streaming of sensory information accordingly. These findings suggest solutions for clinical sensorimotor evaluation after neurological disease, where assessing proprioceptive deficits can improve the recovery path and complement the rehabilitation outcomes.