Prediction of Upper Limb use Three Months after Stroke: A Prospective Longitudinal Study

Biomarkers of Motor Outcomes After Stroke

Predicting motor outcomes after stroke based on clinical judgment alone is often inaccurate and can lead to inefficient and inequitable allocation of rehabilitation resources. Prediction tools are being developed so that clinicians can make evidence-based, accurate, and reproducible prognoses for individual patients. Biomarkers of corticospinal tract structure and function can improve prediction tool performance, particularly for patients with initially moderate to severe motor impairment. Being able to make accurate predictions for individual patients supports rehabilitation planning and communication with patients and families.

Factors Influencing Real-World Use of the More-Affected Upper Limb After Stroke: A Scoping Review

IMPORTANCE

Current interventions are limited in improving use of the more-affected upper limb in real-world daily occupations and functional independence poststroke. A comprehensive understanding of the factors influencing real-world upper limb use is required to develop interventions to improve functional independence poststroke.

OBJECTIVE

To systematically review the factors that influence real-world use of the more-affected upper limb poststroke.

DATA SOURCES

We searched MEDLINE, Embase, PsycINFO, and the Physiotherapy Evidence Database for English-language articles from 2012 to 2023.

STUDY SELECTION AND DATA COLLECTION

Of 774 studies, we included 33 studies that had participants at least age 18 yr who exhibited upper limb impairments poststroke, objectively measured real-world upper limb use using a movement sensor, and measured factors affecting upper limb use. Two reviewers independently screened the abstracts.

FINDINGS

The results were categorized by International Classification of Functioning, Disability and Health domains. Prominent factors were upper limb impairment; motor ability; functional independence; task type; hand dominance; stroke-related factors, including time since stroke; and perception of use of the more-affected upper limb.

CONCLUSIONS AND RELEVANCE

Existing interventions primarily focus on upper limb impairments and motor ability. Our findings suggest that interventions should also incorporate other factors: task type (unilateral vs. bilateral), hand dominance, self-efficacy, and perception of more-affected limb use as active ingredients in improving real-world use of the more-affected upper limb poststroke. We also provide recommendations to use behavioral activation theory in designing an occupation-focused intervention to augment self-efficacy and confidence in use of the more-affected upper limb in daily occupations. Plain-Language Summary: In order to develop interventions to improve functional independence poststroke, occupational therapy practitioners must have a comprehensive understanding of the factors that influence real-world more-affected upper limb use. The study findings provide a set of distinct factors that practitioners can target separately or in combination to improve real-world use of the more-affected upper limb poststroke.

Impact of unilateral and bilateral impairments on bimanual force production following stroke

Large bilateral asymmetry and task deficits are typically observed during bimanual actions of stroke survivors. Do these abnormalities originate from unilateral impairments affecting their more-impaired limb, such as weakness and abnormal synergy, or from bilateral impairments such as incoordination of two limbs? To answer this question, 23 subjects including 10 chronic stroke survivors and 13 neurologically intact subjects participated in an experiment where they produced bimanual forces at different hand locations. The force magnitude and directional deviation of the more-impaired arm were measured for unilateral impairments and bimanual coordination across locations for bilateral impairments. Force asymmetry and task error were used to define task performance. Significant unilateral impairments were observed in subjects with stroke; the maximal force capacity of their more-impaired arm was significantly lower than that of their less-impaired arm, with a higher degree of force deviation. However, its force contribution during submaximal tasks was greater than its relative force capacity. Significant bilateral impairments were also observed, as stroke survivors modulated two forces to a larger degree across hand locations but in a less coordinated manner than control subjects did. But only unilateral, not bilateral, impairments explained a significant amount of between-subject variability in force asymmetry across subjects with stroke. Task error, in contrast, was correlated with neither unilateral nor bilateral impairments. Our results suggest that unilateral impairments of the more-impaired arm of stroke survivors mainly contribute to its reduced recruitment, but that the degree of its participation in bimanual task may be greater than their capacity as they attempt to achieve symmetry.NEW & NOTEWORTHY We studied how unilateral and bilateral impairments in stroke survivors affect their bimanual task performance. Unilateral impairments of the more-impaired limb, both weakness and loss of directional control, mainly contribute to bimanual asymmetry, but stroke survivors generally produce higher force with their more-impaired limb than their relative capacity. Bilateral force coordination was significantly impaired in stroke survivors, but its degree of impairment was not related to their unilateral impairments.

The Role of Ascending Ventral-Tegmental Fibers for Recovery after Stroke

OBJECTIVES

The integrity of cortical motor networks and their descending effector pathway (the corticospinal tract [CST]) is a major determinant motor recovery after stroke. However, this view neglects the importance of ascending tracts and their modulatory effects on cortical physiology. Here, we explore the role of such a tract that connects dopaminergic ventral tegmental midbrain nuclei to the motor cortex (the VTMC tract) for post-stroke recovery.

METHODS

Lesion data and diffusivity parameters (fractional anisotropy) of the ipsi- and contralesional VTMC tract and CST were obtained from 133 patients (63.9 ± 13.4 years, 45 women) during the acute and chronic stage after the first ever ischemic stroke in the middle cerebral artery territory. Degeneration of VTMC tract and CST was quantified and related to clinical outcome parameters (National Institute of Health Stroke Scale with motor and cortical symptom subscores; modified Fugl-Meyer upper extremity score; modified Ranking Scale [mRS]).

RESULTS

A significant post-stroke degeneration occurred in both tracts, but only VTMC degeneration was associated with lesion size. Using multiple regression models, we dissected the impact of particular tracts on recovery: Changes in VTMC tract integrity were stronger associated with independence in daily activities (mRS), upper limb motor impairment (modified Fugl-Meyer upper extremity score) and cortical symptoms (aphasia, neglect) captured by National Institute of Health Stroke Scale compared to CST. Changes in CST integrity merely were associated with the degree of hemiparesis (National Institute of Health Stroke Scale motor subscale).

INTERPRETATION

Post-stroke outcome is influenced by ascending (VTMC) and descending (CST) fiber tracts. Favorable outcome regarding independence (modified Ranking Scale), upper limb motor function (modified Fugl-Meyer upper extremity score), and cortical symptoms (aphasia, neglect) was more strongly related to the ascending than descending tract. ANN NEUROL 2023.

Action observation for upper limb rehabilitation after stroke

BACKGROUND

Action observation (AO) is a physical rehabilitation approach that facilitates the occurrence of neural plasticity through the activation of the mirror-neural system, promoting motor recovery in people with stroke.

OBJECTIVES

To assess whether AO enhances upper limb motor function in people with stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched 18 May 2021), the Cochrane Central Register of Controlled Trials (18 May 2021), MEDLINE (1946 to 18 May 2021), Embase (1974 to 18 May 2021), and five additional databases. We also searched trial registries and reference lists.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of AO alone or associated with physical practice in adults after stroke. The primary outcome was upper limb (arm and hand) motor function. Secondary outcomes included dependence on activities of daily living (ADL), motor performance, cortical activation, quality of life, and adverse effects.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials according to the predefined inclusion criteria, extracted data, assessed risk of bias using RoB 1, and applied the GRADE approach to assess the certainty of the evidence. The reviews authors contacted trial authors for clarification and missing information.

MAIN RESULTS

We included 16 trials involving 574 individuals. Most trials provided AO followed by the practice of motor actions. Training varied between 1 day and 8 weeks of therapy, 10 to 90 minutes per session. The time of AO ranged from 1 minute to 10 minutes for each motor action, task or movement observed. The total number of motor actions ranged from 1 to 3. Control comparisons included sham observation, physical therapy, and functional activity practice.

PRIMARY OUTCOMES

AO improved arm function (standardized mean difference (SMD) 0.39, 95% confidence interval (CI) 0.17 to 0.61; 11 trials, 373 participants; low-certainty evidence); and improved hand function (mean difference (MD) 2.76, 95% CI 1.04 to 4.49; 5 trials, 178 participants; low-certainty evidence).

SECONDARY OUTCOMES

AO did not improve ADL performance (SMD 0.37, 95% CI -0.34 to 1.08; 7 trials, 302 participants; very low-certainty evidence), or quality of life (MD 5.52, 95% CI -30.74 to 41.78; 2 trials, 30 participants; very low-certainty evidence). We were unable to pool the other secondary outcomes (motor performance and cortical activation). Only two trials reported adverse events without significant adverse effects.

AUTHORS' CONCLUSIONS

The effects of AO are small for arm function compared to any control group; for hand function the effects are large, but not clinically significant. For both, the certainty of evidence is low. There is no evidence of benefit or detriment from AO on ADL and quality of life of people with stroke; however, the certainty of evidence is very low. As such, our confidence in the effect estimate is limited because it will likely change with future research.

Changes in upper limb capacity and performance in the early and late subacute phase after stroke

BACKGROUND

The course of spontaneous biological recovery indicates that no essential improvements in upper limb (UL) capacity should be expected 3 months after stroke. Likewise, UL performance as assessed with accelerometers does not seem to increase. However, this plateau may not apply to all patients with stroke.

OBJECTIVES

This study aimed to investigate the changes in UL capacity and performance from 3 to 6 months post-stroke, and the association between patients' UL capacity and actual UL performance.

METHODS

This study was a secondary analysis of a prospective longitudinal cohort study. Patients with UL impairment and first or recurrent stroke were included. Their UL capacity was assessed at 3 and 6 months with the Action Research Arm Test (ARAT) and UL performance was examined with accelerometry and expressed as a use ratio. The association between ARAT and use ratio was examined with multiple regression analyses.

RESULTS

Data from 67 patients were analyzed. It was shown that UL capacity as assessed with ARAT still improved from 3 to 6 months. A clinically meaningful improvement (≥ 6 points on ARAT) was found in 16 (46%) of the 35 patients whose scores allowed for such an increase. Improvements were mainly observed for patients with ARAT scores in the range of 15-51 at 3 months. Conversely, UL performance did not change. Three and 6 months after stroke respectively 69% and 64% of the variation in use ratio was explained by ARAT.

CONCLUSION

While a substantial part of patients improved their UL capacity, UL performance did not change from 3 to 6 months post-stroke. Strategies to remind patients of including their affected UL may encourage the transfer from better capacity to increased performance.

Determinants of Different Aspects of Upper-Limb Activity after Stroke

We examined factors associated with different aspects of upper-limb (UL) activity in chronic stroke to better understand and improve UL activity in daily life. Three different aspects of UL activity were represented by four sensor measures: (1) contribution to activity according to activity ratio and magnitude ratio, (2) intensity of activity according to bilateral magnitude, and (3) variability of activity according to variation ratio. We combined data from a Belgian and Danish patient cohort (n = 126) and developed four models to determine associated factors for each sensor measure. Results from standard multiple regression show that motor impairment (Fugl−Meyer assessment) accounted for the largest part of the explained variance in all sensor measures (18−61%), with less motor impairment resulting in higher UL activity values (p < 0.001). Higher activity ratio, magnitude ratio, and variation ratio were further explained by having the dominant hand affected (p < 0.007). Bilateral magnitude had the lowest explained variance (adjusted R2 = 0.376), and higher values were further associated with being young and female. As motor impairment and biological aspects accounted for only one- to two-thirds of the variance in UL activity, rehabilitation including behavioral strategies might be important to increase the different aspects of UL activity.