Marco Y.C. Pang

Muscle weakness, spasticity and disuse contribute to demineralization and geometric changes in the radius following chronic stroke

SummaryBone health status of the radius in individuals with chronic stroke was evaluated using peripheral quantitative computed tomography. Bone mineral density and cortical thickness on the affected side were compromised when compared with the unaffected side. Muscle weakness, spasticity, and disuse were identified as contributing factors to such changes. IntroductionFollowing a stroke, demineralization and geometric changes occur in bone as a result of disuse and residual impairments, and these can contribute to an increased risk of fragility fractures. MethodsThis study used peripheral quantitative computed tomography (pQCT) to evaluate volumetric bone mineral density and geometry at the midshaft radius in people living with chronic stroke. Older individuals with chronic stroke were recruited. Each subject underwent a pQCT scan of the midshaft radius at the 30% site on both upper limbs. Muscle strength, motor function, spasticity, and chronic disuse were also evaluated. Data from 47 subjects (19 women) were assessed. ResultsA significant difference was found between the two limbs for cortical bone mineral content, cortical bone mineral density, cortical thickness, and polar stress-strain index. There was no significant side-to-side difference in total bone area. Percent side-to-side difference in muscle strength, spasticity, and chronic disuse were significant determinants of percent side-to-side difference in cortical bone mineral content and cortical thickness. ConclusionsThe findings suggest that following chronic stroke, endosteal resorption of the midshaft radius occurred with a preservation of total bone area. Muscle weakness, spasticity, chronic disuse significantly contributed to demineralization and geometric changes in the radius following chronic stroke.

Motor ability and weight status are determinants of out-of-school activity participation for children with developmental coordination disorder

According to the International Classification of Functioning, Disability and Health model endorsed by the World Health Organization, participation in everyday activities is integral to normal child development. However, little is known about the influence of motor ability and weight status on physical activity participation in children with developmental coordination disorder (DCD). This study aimed to (1) compare motor performance, weight status and pattern of out-of-school activity participation between children with DCD and those without; and (2) identify whether motor ability and weight status were determinants of participation patterns among children with DCD. We enrolled 81 children with DCD (boys, n = 63; girls, n = 18; mean age, 8.07 ± 1.5 years) and 67 typically developing children (boys, n = 48; girls, n = 19; mean age, 8.25 ± 1.6 years). Participation patterns (diversity, intensity, companionship, location, and enjoyment) were evaluated with the Children Assessment of Participation and Enjoyment. Motor ability was evaluated with the Movement Assessment Battery for Children, second edition (MABC-2). Other factors that may influence participation such as age, gender, and body weight were also recorded. Analysis of variance was used to compare outcome variables of the two groups, and significant determinants of activity participation were identified by multiple regression analysis. Children with DCD participated in fewer activities (i.e., limited participation diversity) and participated less frequently (i.e., limited participation intensity) than their typically developing peers; however, companionship, location of participation, and enjoyment level did not differ between the two groups. Children in the DCD group demonstrated significantly worse motor ability as assessed by the MABC-2. Further, a greater proportion of children in the DCD group were in the overweight/obese category compared with their typically developing peers. After accounting for the effects of age and gender, motor ability and weight category explained 7.6% and 5.0% of the variance in participation diversity, respectively, for children with DCD. Children with DCD showed less diverse and less intense out-of-school activity participation than typically developing children. Motor impairment and weight status were independently associated with the lower participation diversity. Interventions aiming at improving participation for children with DCD should target weight control and training in motor proficiency. Further study is needed to identify other factors that may hinder participation in this group of children.

A 19-week exercise program for people with chronic stroke enhances bone geometry at the tibia: a peripheral quantitative computed tomography study

BackgroundWe assessed the impact of a 19-week exercise program on bone health in chronic stroke.ResultsThose who underwent the program reported significantly more gain in tibial trabecular bone content and cortical bone thickness on the affected side.ConclusionRegular exercise is thus beneficial for enhancing bone health in this population.

Effects of group-based versus individual-based exercise training on motor performance in children with developmental coordination disorder : a randomized controlled pilot study

OBJECTIVE To compare the effects of group-based and individual-based motor skill training on motor performance in children with developmental coordination disorder. DESIGN Randomized controlled pilot intervention study. SUBJECTS/PATIENTS Twenty-three children (4 girls) with developmental coordination disorder (mean age (standard deviation (SD)) 8 years (1 year and 2 months)). METHODS Twelve children were randomly assigned to undergo a motor training programme once a week for 8 consecutive weeks in a group setting, and 11 children received the same training on an individual basis during the same period. Each child was also instructed to perform home exercises on a daily basis. The Movement Assessment Battery for Children (MABC) was used to assess motor ability. Home exercise compliance and parental satisfaction with the programmes were also evaluated. RESULTS A significant reduction in the MABC total impairment score was found following both group-based (mean -4.4 (SD 5.0), p = 0.003) and individual-based training (mean -5.2 (SD 5.1), p = 0.016). However, the change in total impairment score did not differ significantly between the 2 groups (p = 0.379). There was similarly no significant between-group difference in home exercise compliance (p = 0.288) and parental satisfaction (p = 0.379). CONCLUSION Group-based training produced similar gains in motor performance to individual-based training. Group-based training may be the preferred treatment option due to the associated cost savings.

Whole-body vibration has no effect on neuromotor function and falls in chronic stroke.

PURPOSE Whole-body vibration therapy has gained increasing popularity in enhancing neuromotor function in various patient populations. It remains uncertain, however, whether whole-body vibration is beneficial when used in stroke patients. The aim of this randomized controlled trial was to examine the efficacy of whole-body vibration in optimizing neuromotor performance and reducing falls in chronic stroke patients. METHODS Eighty-two chronic stroke patients were randomly assigned to either the experimental group or control group. The experimental group received 9-15 min of whole-body vibration (vertical vibration; frequency = 20-30 Hz. amplitude = 0.44-0.60 mm, peak acceleration = 9.5-15.8 m·s or 0.97-1.61 U of Earth gravitational acceleration (g) while performing a variety of dynamic leg exercises on the vibration platform. The control group performed the same exercises without vibration. The subjects underwent their respective training three times a week for 8 wk. Balance (Berg balance scale), mobility (10-m walk test and 6-min walk test), knee muscle strength (isokinetic dynamometry), and fall-related self-efficacy (activities-specific balance confidence scale) were assessed at baseline, immediately after the 8-wk training and at a 1-month follow-up. The incidence of falls was recorded until 6 months after the termination of training. RESULTS Intention-to-treat analysis revealed similar significant improvement in all balance, mobility, muscle strength, and fall-related self-efficacy measures in both groups after the 8-wk treatment period (P < 0.001), and these were maintained at the 1-month follow-up. The incidence of falls did not differ significantly between the two groups (P > 0.05). CONCLUSIONS The addition of the presently used whole-body vibration paradigm to a leg exercise protocol was no more effective in improving neuromotor performance and reducing the incidence of falls than leg exercises alone in chronic stroke patients who have mild to moderate motor impairments.

Balance, falls, and bone health: Role of exercise in reducing fracture risk after stroke

Fractures occur frequently in people living with stroke and have high personal, social, and economic costs for these individuals, their families, and the community. Exercise to reduce the risk of fragility fractures is a relatively new application in stroke rehabilitation but is a promising treatment with the potential to reduce the incidence of falls as well as maintain or improve bone health. In this article, we outline fracture risk factors and provide an overview of exercise interventions aimed at reducing fracture risk poststroke. Although randomized controlled trials support the use of exercise to reduce fracture risk factors poststroke, the body of literature is small and further studies are required. Further, the optimal dose of exercise and the additive effects of pharmacology on fracture risk need to be determined. Given the many health benefits associated with exercise, it should be considered an important modality for the management of falls and maintenance of bone health following stroke.

Effects of Whole-Body Vibration on Sensorimotor Performance in People With Parkinson Disease: A Systematic Review

Background Earlier studies show that whole-body vibration (WBV) has beneficial effects on neuromuscular performance in older adults and may be a viable treatment option for people with Parkinson disease (PD). Purpose This systematic review was aimed at determining whether WBV improves sensorimotor performance in people with PD. Data Sources The sources used in this review were MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Excerpta Medica database (EMBASE), the Cochrane Database of Systematic Reviews, and the Physiotherapy Evidence Database (PEDro) (last searched in April 2010). Study Selection Randomized and nonrandomized controlled studies examining the effects of WBV in people with PD were selected. Six studies fulfilled the selection criteria and were included in this review. Data Extraction The PEDro score was used to evaluate methodological quality. The effects of WBV on various sensorimotor outcomes were noted. Data Synthesis Methodological quality was rated as good for 1 study (PEDro score of 6), fair for 4 studies (PEDro score of 4 or 5), and poor for 1 study (PEDro score of 2). Two studies showed that, compared with no intervention, WBV treatment led to significant reductions in tremor and rigidity, as measured with the Unified Parkinson Disease Rating Scale (UPDRS). The findings for other UPDRS cluster scores were conflicting, however. Two studies showed that longer-term WBV (3–5 weeks) did not result in better sensorimotor outcomes than conventional exercise training. Limitations The studies reviewed here are limited by their methodological weaknesses and small, heterogeneous samples. Conclusions There is insufficient evidence to prove or refute the effectiveness of WBV in enhancing sensorimotor performance in people with PD (ie, grade D recommendations). More good-quality trials are needed to establish the clinical efficacy of WBV in improving sensorimotor function in people with PD.

ASSOCIATION OF DEPRESSION AND PAIN INTERFERENCE WITH DISEASE-MANAGEMENT SELF-EFFICACY IN COMMUNITY-DWELLING INDIVIDUALS WITH SPINAL CORD INJURY

OBJECTIVE To determine factors influencing disease-management self-efficacy in individuals with spinal cord injury. DESIGN A cross-sectional study. SUBJECTS/PATIENTS Forty-nine community-dwelling individuals with chronic spinal cord injury (mean age 44 years) participated in the study. METHODS Each subject was evaluated for disease-management self-efficacy (Self-efficacy for Managing Chronic Disease), depression (10-item Center for Epidemiologic Studies Depression Scale), pain interference (Pain Interference Scale), and availability of support (Interpersonal Support Evaluation List short form). Multiple regression analysis was performed to determine the relative contributions of these factors to disease-management self-efficacy. RESULTS The mean disease-management self-efficacy score was 6.5 out of 10 (standard deviation 1.6). Bivariate correlation analysis showed that higher self-efficacy was significantly correlated with longer time since injury (r = 0.367, p = 0.010), better social support (r = 0.434, p = 0.002), lower pain interference (r = -0.589, p <0.001), and less severe depressive symptoms (r=-0.463, p=0.001). In multiple regression analysis, only lower pain interference and less severe depressive symptoms were significantly associated with higher disease-management self-efficacy (F 4,44=10.249, R2=0.482, p<0.001). CONCLUSION Disease-management self-efficacy is suboptimal in many community-living people with spinal cord injury. This research suggests that rehabilitation of patients with spinal cord injury should include self-efficacy-enhancing strategies. Alleviation of depressive symptoms and pain self-management may be important for improving disease-management self-efficacy in this population, but this requires further study.

DETERMINANTS OF IMPROVEMENT IN WALKING CAPACITY AMONG INDIVIDUALS WITH CHRONIC STROKE FOLLOWING A MULTI-DIMENSIONAL EXERCISE PROGRAM

OBJECTIVE To identify the determinants of improvement in walking capacity following therapeutic exercise in chronic stroke survivors. DESIGN A secondary analysis of data obtained from a prospective, single-blind, randomized controlled intervention trial. SUBJECTS Sixty-three community-dwelling individuals (mean age = 65 years, age range = 50-87 years) with a chronic stroke (post-stroke duration: mean = 5.5 years, range = 1-28 years). METHODS Subjects were randomized into a leg exercise group (n = 32) or an arm exercise group (n = 31). Subjects in each group underwent 3 1-hour exercise sessions per week for 19 weeks. Walking capacity, cardiorespiratory fitness, isometric knee extensor muscle strength, balance ability, and balance confidence were evaluated before and after the interventions. Multiple regression analysis was performed to identify the determinants of improvement in walking capacity. RESULTS After controlling for age, gender, post-stroke duration, and baseline walking capacity, gain in paretic leg muscle strength and peak oxygen consumption remained independently associated with gain in walking capacity (R2 = 0.229). CONCLUSION Enhancement of cardiorespiratory fitness and paretic leg muscle strength are both significant determinants in improving walking capacity among chronic stroke survivors. However, the rather weak relationship (R2 = 0.229) indicates that other factors not measured in this study may also contribute to the improvement in walking capacity.

Sensory organization of balance control in children with developmental coordination disorder

This study aimed to (1) compare functional balance performance and sensory organization of postural control between children with and without developmental coordination disorder (DCD) and (2) determine the association between postural control and participation diversity among children with DCD. We recruited 81 children with DCD and 67 typically developing children. Balance was evaluated with the Sensory Organization Test (SOT) and the Movement Assessment Battery for Children-2 (Movement ABC-2). Participation patterns were evaluated using the Children Assessment of Participation and Enjoyment assessment. Analysis of variance was used to compare outcome variables between the two groups. A multiple regression analysis was performed to examine the relationship between participation diversity and balance performance in children with DCD. The DCD group had significantly lower Movement ABC-2 balance scores, SOT-derived equilibrium scores, and sensory ratios than the control group (p<0.05). However, only the Movement ABC-2 balance score was significantly associated with participation diversity in children with DCD. After accounting for the effects of age and gender, Movement ABC-2 balance score remained significantly associated with participation diversity, explaining 10.9% of the variance (F(change1,77) = 9.494, p = 0.003). Children with DCD demonstrate deficits in sensory organization of balance control. This suboptimal balance ability contributes to limited participation in activities.