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Parkinson’s disease (PD) reduces independence and quality of life through deterioration of upper limb motor function. Transcranial direct current stimulation (tDCS) may offer an alternative, adjunctive therapy for PD. However, the efficacy of tDCS for upper limb motor rehabilitation in PD is unknown. In this systematic review, evidence is compiled regarding the effects of tDCS on upper limb motor function in PD. Studies of tDCS applied to PD patients that assessed upper limb motor function, conducted between January 2000 and November 2018, were screened for inclusion via a systematic search of Medline, Cochrane, PsycINFO, EMBASE, CINAHL, and Web of Science. Ten out of 606 studies were included and their findings synthesized into five categories regarding the effects of tDCS on: (1) Unified Parkinson’s Disease Rating Scale motor section (UPDRS III), (2) upper limb motor tasks, (3) manual dexterity, (4) reaction time, and (5) neurophysiology. When applied to the primary motor cortex, tDCS may improve UPDRS III and the speed and force of movement. Considerable variation was found in tDCS parameters and further study is needed to clarify the long-term effects of tDCS on both simple and complex motor tasks and to compile relevant neurophysiological evidence.

Previous studies have shown that balance training could reduce falls in people with Parkinson disease. However, it remains unclear whether exercise can reduce injurious falls. The objective of present study was to determine whether multisystem balance training could reduce injurious falls and modify targeted fall risk factors in Parkinson disease nonfallers and single fallers. Participants were randomly assigned to an 8-wk balance group (experimental, n = 41) or an upper limbs group (control, n = 43). Outcomes examined at posttraining and 12-mo follow-up were: (1) injurious fall risk (ratio of noninjurious fallers to injurious fallers); (2) two potential fall risk factors based on Balance Evaluation Systems Test scores and dual-task timed-up-and-go times. At posttraining, results indicated that there were no injurious falls, and fewer experimental participants were found in high fall risk cohorts based on Balance Evaluation Systems Test scores and dual-task timed-up-and-go times (P < 0.05). At 12-mo follow-up, the number of injurious fallers was lower in experimental group (P < 0.05). There was also a marginally lower percentage of experimental group in the high fall risk cohort based on Balance Evaluation Systems Test scores (P = 0.059). The findings conclude that multisystem balance training potentially reduces injurious fall risk up to 12-mo posttraining and lowers balance-related fall risks in people with Parkinson disease.

Background: In Parkinson’s disease (PD), sustained aerobic exercise is a promising therapy in delaying motor disability. Brisk walking is a moderate intensity aerobic training, which could be translated to community practice at low cost, but its effects on motor symptoms remains unclear. Objective: To determine the effectiveness of a six-month brisk walking and balance program in alleviating motor symptoms, and promoting functional, gait, and balance performance in people with PD. Methods: Seventy individuals with mild to moderate PD were randomly assigned to a brisk walking (BW) group or an active control (CON) group. BW group received ten 90-minute supervised brisk walking and balance exercise for six months (weeks 1–6: once/week, weeks 7–26: once/month). CON group received upper limb training. Both groups performed 2-3 self-practice sessions weekly. Primary outcome was Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) motor score. Secondary outcomes were fast gait speed (FGS), timed-up-and-go (TUG) time, six-minute walk distance (6MWD), and Mini-Balance Evaluation Systems Test (Mini-BEST) score. Results: Sixty-four participants (33 BW/31 CON) completed training. BW group showed greater significant decreases from baseline than CON group in MDS-UPDRS motor score after six weeks (–5.5 vs –1.6, p

INTRODUCTION Explicit motor sequence learning is impaired in Parkinson's disease (PD). Transcranial direct current stimulation (tDCS) applied over the motor cortex in healthy can improve explicit motor learning, but comparative effects in PD are unknown. This exploratory study aims to examine the effect of single session tDCS on explicit motor sequence learning in PD. METHODS Thirty-three people with mild to moderate PD learnt a short and long finger tapping sequence with their right hand. Participants received either anodal, cathodal, or sham tDCS applied over the left primary motor cortex during task practice. Single- and dual-task finger tapping performance was assessed before and after task practice and functional near-infrared spectroscopy used to measure task related changes of oxygenated haemoglobin. RESULTS Finger tapping performance of short and long sequences under single-task conditions significantly improved following practice (p = 0.010 and p

Postural instability and walking difficulties are the most disabling symptoms in Parkinson disease (PD), leading to falls, physical injuries, functional decline and early institutionalization. Medical, surgical and rehabilitation are the mainstay of management for balance and gait disorders. Evaluation of balance and gait disorders is crucial to determine the problems of the patients so that targeted treatment can be given. Postural instability manifests as reductions in limits of stability, postural adjustment, and postural responses. Gait disorders comprise reduced gait speed, short stride length, freezing of gait, and dual-task deficits. Postural instability and gait disorders can be evaluated using reliable and validated clinical tests, measurement scales, questionnaires and technological equipment. Objective clinical tests and measurement scales require simple equipment and needs a short time to complete the tests. Questionnaires are useful to reflect patients’ perceived balance and gait ability. Technological equipment can be costly but they can increase the measurement sensitivity. The clinical tests used to evaluate postural instability include retropulsion tests, Functional reach test, and one-leg-stance test, whilst those for gait disorders include single or dual-task walk test, timed-up-and-go-test, and 6-minute walk test. Measurement scales including Berg’s balance scale, mini-Balance evaluation system test and Tinetti mobility test, are used to assess overall balance and gait limitations. Most of the measurement scales have cut-off scores for predicting fall risk. Validated questionnaires such as Activities-specific balance confidence scale and Fall efficacy scale evaluate one’s perceived level of balance confidence. Freezing-of-gait questionnaire subjectively assess the severity of freezing of gait. Most of the technological equipment are bulky, laboratory-based and may require a long time to complete the test and/or to analysis the data. Nowadays, body worn sensors is getting more popular because they allow measurement to be taken anywhere including patients’ home and in the community. Algorithm has been built in some systems to shorten the data analyzing time. There are many choices of outcome measures and clinicians/researchers can choose the evaluation methods that is best for their measurement purposes.

Parkinson disease (PD) is a progressive, neurodegenerative movement disorder with symptoms reflecting various impairments and functional limitations, such as postural instability, gait disturbance, immobility and falls. In addition to pharmacological and surgical management of PD, exercise and physical therapy interventions are also being actively researched. This Review provides an overview of the effects of PD on physical activity - including muscle weakness, reduced aerobic capacity, gait impairment, balance disorders and falls. Previously published reviews have discussed only the short-term benefits of exercises and physical therapy for people with PD. However, owing to the progressive nature of PD, the present Review focuses on the long-term effects of such interventions. We also discuss exercise-induced neuroplasticity, present data on the possible risks and adverse effects of exercise training, make recommendations for clinical practice, and describe new treatment approaches. Evidence suggests that a minimum of 4 weeks of gait training or 8 weeks of balance training can have positive effects that persist for 3-12 months after treatment completion. Sustained strength training, aerobic training, tai chi or dance therapy lasting at least 12 weeks can produce long-term beneficial effects. Further studies are needed to verify disease-modifying effects of these interventions.

Parkinson's disease is the second most common neurodegenerative disease with a prevalence rate of 1-2 per 1000 of the population worldwide. Pharmacological management is the mainstay of treatment. Despite optimal medication, motor impairment particularly balance and gait impairment persist leading to various degree of disability and reduced quality-of-life. The present review describes motor impairment including postural impairment, gait dysfunction, reduced muscle strength and aerobic capacity and falls. Physical therapy and complementary exercises have been proven to improve motor performance and functional mobility. Evidence on the efficacy of physical therapy and complementary exercises is presented in this review. These exercises include gait training with cues, gait training with treadmill, Nordic walking, brisk walking, balance training, virtual reality interventions, Tai Chi and dance. All these treatment interventions produce short-term beneficial effects and some interventions demonstrate long-term benefit. Gait training with treadmill enhance walking performance and the effects sustain for 3-6 months. Balance training improves balance, function and reduces fall rate, and these effects carry over to at least 12 months after training ended. Sustained Tai Chi for 6 months, dance therapy for 12 months, progressive resistive training for 24 months alleviates the PD motor symptoms, suggesting that they could slow down PD progression. Based on this evidence, individuals with PD are encouraged to sustain their training in order to improve/maintain their physical ability and to combat the progression of PD.

Background The short-term beneficial effects of repetitive transcranial magnetic stimulation (rTMS) on motor signs in Parkinson's disease (PD) have been addressed by previous meta-analyses while its long-term effects remain undetermined. Although deterioration of walking and upper limb function greatly affects the participation in activities and quality of life of PD sufferers, the effect of rTMS thereon has not been systematically studied. Objective This systematic review aimed to examine the efficacy of rTMS on improving physical function and motor signs over the short- and long-terms in people with PD. Methods Five electronic databases were systematically searched for English language full-text articles using relevant search terms. Only randomized placebo-controlled trials investigating the effects of rTMS in PD were considered. The primary outcomes were walking performance, upper limb function, and unified Parkinson's disease rating scale (UPDRS) section III. Trials with similar outcomes were pooled by calculating Hedges' g using random-effects model. Results Twenty-two trials comprising 555 people with PD were included. Pooled estimates of effect of rTMS indicated significantly improved short-term upper limb function (Hedges' g, 0.40, P = 0.007), short-term (Hedges' g, 0.61, P = 0.03) and long-term walking performance (Hedges' g, 0.89, P = 0.03), short-term (Hedges' g, 0.31, P = 0.003) and long-term (Hedges' g, 0.54, P = 0.003) UPDRS III scores. Subgroup analyses suggest a more prominent effect for M1 stimulation. Meta-regression revealed that a greater number of total stimulation pulses were associated with more UPDRS III improvements over the long-term. Conclusion The pooled evidence suggests that rTMS improves upper limb function in the short-term, walking performance and UPDRS III in the short- and long-terms in PD sufferers. Further studies are required to develop optimal rTMS therapeutic protocols for PD.

Objectives To investigate the short- and long-term effects of a task- and context-specific balance training program on dynamic balance and functional performance, and to explore the effects on preventing total and injurious falls in parkinsonian nonfallers. Design A randomized controlled trial with group allocation single-blinded to the assessor. Setting Community centers, malls, and outdoor parks. Participants Nonfallers with Parkinson disease (PD) (N=70; mean age ± SD, 61.2±8.8y) randomly assigned to either a balance (BAL) group (n=32) or a control (CON) group (n=38). Interventions The BAL group received 4 weeks of indoor and 4 weeks of outdoor balance training (with a 2-h session per week). The CON group received 8 weeks of upper limb training at the same dosage. Both groups were instructed to perform 3 hours of home exercise weekly posttraining. Main Outcome Measures (1) Dynamic balance performance: Mini-Balance Evaluation Systems Test (Mini-BESTest); (2) Functional performance: functional reach (FR), 5 times sit-to-stand (FTSTS), 1-leg-stance (OLS), Timed Up and Go (TUG), and dual-task TUG tests; (3) Fall-related outcomes: ratios of total nonfallers to fallers and noninjurious fallers to injurious fallers, total and injurious fall rates, times to first falls and injurious falls. Results Sixty-eight participants completed training. A total of 7 patients (10%) withdrew before the 6-month follow-up, but not because of any adverse effects. At immediate and 6 months posttraining, the BAL group showed significantly greater improvements (from baseline) than the CON group in Mini-BESTest total scores, FR distances, and OLS times, together with greater time reductions in FTSTS, TUG, and dual-task TUG tests (all P Conclusions This task- and context-specific balance training program improved the dynamic balance and fall-prone functional performance of PD nonfallers for up to 6 months after training. The BAL group showed a reduction in injurious fallers.

Postural instability and falls are complex and disabling features of Parkinson’s disease (PD) and respond poorly to anti-Parkinsonian medication. There is an imperative need to evaluate the effectiveness of exercise interventions in enhancing postural stability and decreasing falls in the PD population. The objectives of our study were to determine the effects of exercise training on the enhancement of balance and gait ability and reduction in falls for people with PD and to investigate potential factors contributing to the training effects on balance and gait ability of people with PD. We included 25 randomized control trials of a moderate methodological quality in our meta-analysis. The trials examined the effects of exercise training on balance and gait ability and falls against no intervention and placebo intervention. The results showed positive effects of exercise intervention on enhancing balance and gait performance (Hedges’ g = 0.303 over the short-term in 24 studies and 0.419 over the long-term in 12 studies; P < .05) and reducing the fall rate (rate ratio = 0.485 over the short-term in 4 studies and 0.413 over the long-term in 5 studies; P < .05). The longest follow-up duration was 12 months. There was no evidence that training decreased the number of fallers over the short- or long-term ( P > .05). The results of our metaregression and subgroup analysis showed that facility-based training produced greater training effects on improving PD participants’ balance and gait ability ( P < .05). The findings support the application of exercise training to improve balance and gait ability and prevent falls in people with PD.

Previous studies have demonstrated that exercise interventions can improve balance and gait performance in people with Parkinson's disease (PD), but most training did not target all balance domains and was conducted mainly indoors.To investigate the short- and long-term effects of a multi-dimensional indoor and outdoor exercise programme on balance, balance confidence and gait performance in people with PD.Eligible subjects with PD were randomly assigned to an eight-week indoor and outdoor balance training (EXP, N = 41) group or upper limb exercise (CON, N = 43) group. Outcome measures included BESTest total and subsection scores, gait speed, dual-task timed-up-and-go (dual-task TUG) time and Activities-specific Balance Confidence (ABC) score. All outcomes were assessed before training (Pre), immediately after intervention (Post) and at six-month (FU6m) and twelve-month (FU12m) follow-ups.Immediately after training, EXP group showed more significant improvements than CON group in BESTest total and subsection scores, gait speed and dual-task TUG time (p 0.05). At both FU6m and FU12m, EXP group showed significantly greater gains than CON group in BESTest total and subsection scores and dual-task TUG time (p 0.05). EXP group also showed significantly greater increase in the gait speed than CON group at FU6m (p 0.05).The positive findings of this study provide evidence that this multi-dimensional balance training programme can enhance balance and dual-task gait performance up to 12-month follow-up in people with PD.

Upper limb weakness and incoordination is a common disability following ischemic stroke. Previous studies have showed that the single application of external counterpulsation (ECP) and intermittent theta burst stimulation (iTBS) can effectively enhance the cortical motor excitability and facilitate recovery. However, it remains uncertain if sequential application of these therapies would further augment the recovery. We hypothesize a synergistic effect of ECP followed by iTBS to upper limb function may happen through improvements in both cerebral perfusion and neuron excitability.

Background. Fear of falling has been identified as an important and independent fall-risk predictor in patients with Parkinson’s disease (PD). However, there are inconsistent findings on the effects of balance and gait training on balance confidence. Objective. To explore whether balance and gait training with augmented feedback can enhance balance confidence in PD patients immediately after treatment and at 3- and 12-month follow-ups. Methods. A total of 51 PD patients were randomly assigned to a balance and gait training (BAL) group or to an active control (CON) group. The BAL group received balance and gait training with augmented feedback, whereas CON participants received lower-limb strength training for 12 weeks. Outcome measures included Activities-Specific Balance Confidence (ABC) Scale, limits-of-stability test, single-leg-stance test, and spatiotemporal gait characteristics. All tests were administered before intervention (Pre), immediately after training (Post), and at 3 months (Post3m) and 12 months (Post12m) after treatment completion. Results. The ABC score improved marginally at Post and significantly at Post3m and Post12m only in the BAL group ( P < .017). Both participant groups increased their end point excursion at Post, but only the BAL group maintained the improvement at Post3m. The BAL group maintained significantly longer time-to-loss-of-balance during the single-leg stance test than the CON group at Post3m and Post12m ( P < .05). For gait characteristics, both participant groups increased gait velocity, but only the BAL group increased stride length at Post, Post3m, and Post12m ( P < .017). Conclusions. Positive findings from this study provide evidence that BAL with augmented feedback could enhance balance confidence and balance and gait performance in patients with PD.

To examine whether training under visual cues could enhance motor cortical excitability and intracortical inhibition in individuals with Parkinson's disease (PD).This was a single blinded cross-over study. Eight individuals with PD received two sessions of 30-min pinch-grip training with and without visual cues. The visual cue was given in form of an arrow that indicated the pre-set force level on a computer screen. Outcome measures consisted of peak motor evoked potential (MEP) and cortical silent period (CSP) of the first dorsal interosseus as well as behavioural tests including Purdue pegboard test, tapping speed in 30s, and the maximum pinch grip force exerted by the thumb and index finger.After cued training, there were significant increases in the peak MEP, CSP duration and tapping speed (all p0.05). In contrast, there was no change in all outcome measures after training under the non-cued condition.Thirty minutes of pinch-grip training with visual cues could enhance motor cortical excitability and intracortical inhibition in individuals with PD.The findings on the neurophysiological changes after cued-training may inform further clinical application of visual cues to maximize motor improvement and corticomotor plasticity in people with PD.

Background Previous studies employed demanding and complex hand tasks to study the brain activation in people with Parkinson's Disease (PD). There is inconsistent finding about the cerebellar activity during movement execution of this patient population. Objectives This study aimed to examine the brain activation patterns of PD individuals in the on-state and healthy control subjects in a simple finger tapping task. Methods Twenty-seven patients with PD and 22 age-matched healthy subjects were recruited for the study. Subjects were instructed to perform simple finger tapping tasks under self- and cue-initiated conditions in separate runs while their brain activations were captured using fMRI. Results Healthy subjects had higher brain activity in contralateral precentral gyrus during the self-initiated task, and higher brain activity in the ipsilateral middle occipital gyrus during the cue-initiated task. PD patients had higher brain activity in the cerebellum Crus I (bilateral) and lobules VI (ipsilateral) during the self-initiated task and higher brain activity in the contralateral middle frontal gyrus during the cue-initiated task. When compared with healthy controls, PD patients had lower brain activity in the contralateral inferior parietal lobule during the self-initiated task, and lower brain activity in the ipsilateral cerebellum lobule VIII, lobule VIIB and vermis VIII, and thalamus during the cue-initiated task. Conjunction analysis indicated that both groups had activation in bilateral cerebellum and SMA and ipsilateral precentral gyrus and postcentral gyrus during both self- and cue-initiated movement. Individuals with PD exhibited higher brain activity in the executive zone (cerebellum Crus I and II) during self-initiated movement, and lower brain activity in the sensorimotor zone (i.e. lobule VIIb and VIII of the cerebellum) during cue-initiated movement. Discussions The findings suggest that individuals with PD may use more executive control when performing simple movements.

To compare the ankle muscle strength and torque-angle relationship between individuals with Parkinson's disease (PD) and participants without impairments.Cross-sectional, exploratory study.Motor control laboratory in a university.Convenience sample of community-dwelling individuals with PD (n=59) recruited from a PD self-help group and age-matched participants without impairments (n=37) recruited from community older adult centers.Not applicable.Peak torque and angle-torque profile during concentric and eccentric contraction of ankle dorsiflexors and plantarflexors at 2 different angular speeds (45 and 90°/s).The PD group displayed lower muscle peak torque values than participants without impairments in all test conditions. Generally, concentric strength was more compromised, with a greater between-group difference (Cohen d=1.29-1.60) than eccentric strength (Cohen d=.81-1.37). Significant group by angular speed interaction was observed in ankle plantarflexion concentric peak torque (P.001), indicating that muscle weakness was more pronounced when the angular speed was increased. The group by joint angle interaction in concentric contraction of ankle plantarflexors at 90°/s was also significant (P.001), revealing that the between-group difference in torque values became increasingly more pronounced when the joint was moving toward the end range of the ankle plantarflexion. This exaggerated ankle plantarflexor muscle weakness at the end range was significantly correlated with clinical balance measures (P.05).Muscle weakness in PD is influenced by contraction type, angular speed, and joint range. Exaggerated weakness is found in concentric contraction of ankle plantarflexors, particularly when the angular speed is high and the muscle is in shortened lengths.

The present study aimed to examine the contribution of gait impairment, postural stability and muscle weakness to the level of fear of falling in people with Parkinson's disease (PD). Fifty-seven community-dwelling individuals with PD completed the study. Fear of falling was assessed by the Activities-specific Balance Confidence (ABC) scale. Postural stability and gait difficulty were determined by the posture and gait subscores of the Unified Parkinson's Disease Rating Scale (UPDRS-PG). A Cybex dynamometer was used to measure isokinetic knee muscle strength. Individuals with PD achieved a mean ABC score of73.6±19.3. In the multiple regression analysis, after accounting for basic demographics, fall history and disease severity, the UPDRS-PG score remained independently associated with the ABC score, accounting for 13.4% of the variance (P<0.001). The addition of knee muscle strength significantly improved the prediction model and accounted for an additional 7.3% of the variance in the ABC score (P<0.05). This is the first study to demonstrate that the UPDRS-PG score and knee muscle strength are important and independent determinants of the level of fear of falling in individuals with PD. Improving balance, gait stability and knee muscle strength could be crucial in promoting balance confidence in the appropriately targeted PD population.

Background Previous studies focused on describing successful sit-to-stand (STS) performance in patients with Parkinson disease (PD). Little is known about why these patients fail to perform this transfer activity. Objective This study aimed to determine the role of dynamic stability and limb support in governing successful STS performance in patients with PD and to determine the limits of recovery for discriminating between successful and failed STS trials. Design This was a cross-sectional study. Methods Twenty-eight patients with PD were instructed to perform the STS task. Kinematic data on 18 successful trials and 14 failed trials (when the patients fell backward) were collected with a motion analysis system. Dynamic stability was determined by the anteroposterior position of the body's center of mass (COM) relative to the base of support (BOS) and by the anteroposterior velocity of the COM relative to the BOS (VelocityCOM/BOS,AP). Limb support was characterized by the hip height (Heighthip). Results The findings revealed no between-group (“risers” versus “fallers”) differences in dynamic stability. The fallers shifted their COM in a significantly more anterior position to compensate for their lower VelocityCOM/BOS,AP at seat-off. It was in the vertical direction that the fallers had significantly reduced peak COM velocity (VelocityCOM,vertical) and lower corresponding Heighthip than the risers. Results of a stepwise regression model showed that VelocityCOM/BOS,AP and Heighthip at the instant of peak VelocityCOM,vertical could best predict the STS outcome (success versus failure), with an overall prediction accuracy of 87.5%. The limit differentiating successful from failed STS trials was: Heighthip=−0.814 VelocityCOM/BOS,AP + 0.463. Limitations All of the patients were community dwelling and had a moderate level of disease severity. The results cannot be generalized to those who are institutionalized or with advanced PD. Conclusions Limb support and ill-timed peak forward COM velocity, rather than dynamic stability, play the dominant roles in determining successful STS performance in patients with PD.

Objective: To compare the effects of speed-dependent treadmill training on gait and balance performance in patients with sub-acute stroke. Design: Single-blinded randomized controlled trial. Subjects: A total of 26 patients with sub-acute stroke were r a n d omly assigned to experimental (n = 13) and control (n = 13) groups. Methods: Subjects in the experimental group underwent short interval walking trials with stepwise increases in treadmill speed (speed-dependent treadmill training), following the principles of sprint training. Control subjects received gait training on the treadmill at a steady speed. Gait speed, stride length, cadence, and Berg’s Balance Score were recorded and analysed before and after the 10 training sessions. Results: Results of 2-way repeated measures analysis of variance showed significant group×time interactions for gait speed and stride length (p < 0.05). Within each subject group there were improvements in all gait parameters and Berg’s Balance Score after the training programme. In addition, the experimental group showed significantly larger increases in gait speed (mean 0.15 m/s, 95% confidence interval 0.04– 0.26) and stride length (mean 0.16 m, 95% confidence inter val 0.02–0.30) than the control subjects. Conclusion: Speed-dependent treadmill training in patients with sub-acute stroke resulted in larger gains in gait speed and stride length compared with steady speed. The positive findings provide evidence for clinical practice of speeddependent treadmill training in enhancing gait function after stroke.

The study aimed to compare the fall characteristics between parkinsonian single (P-SF) and recurrent fallers (P-RF), and the clinical features among parkinsonian non-fallers (P-NF), P-SF, P-RF and age-matched healthy controls. As many as 72 patients with PD and 74 healthy subjects completed the study. Each subject was evaluated for gait speed, timed up-and-go test, one-leg-stance test, six-minute walk test, five-times-sit-to-stand test, and Activities-specific Balance Confidence (ABC) scale at baseline. Subjects were then followed up for 12 months by telephone interview to record the fall incidence and fall characteristics. Among the PD patients, 12 fell once (P-SF) and 13 fell 2-29 times (P-RF), accounting for a total of 133 falls in the 12-month follow-up period. The most common fall-related activity for both P-SF and P-RF was walking. P-SF fell mostly outdoors due to "tripping", while P-RF mostly fell at home due to "muscle giving way". Clinical measures indicated that P-SF did not differ from P-NF. However, P-RF had significantly longer five-times-sit-to-stand time, shorter 6-min walk distance, and lower ABC score than P-SF. P-RF could be distinguished from P-SF by fall characteristics (i.e. location and perceived causes of falls), and by clinical measures including leg muscle weakness, reduced exercise endurance and increased level of fear of falling. Findings from the present study suggest that P-NF/P-SF and P-RF may require different intervention strategies to prevent future falls.

Previous literature suggested that muscle forces applied to the skeleton may be an important factor in increasing bone mineral density (BMD). This purpose of this study was to determine whether trunk rigidity and trunk muscle strength were associated with lumbar spine BMD in patients with Parkinson's disease (PD). Forty-three PD patients and 29 controls participated in this study. Dual-energy X-ray absorptiometry was used to measure lumbar spine BMD of PD patients. Additionally, an isokinetic dynamometer was used to evaluate trunk rigidity and trunk muscle strength of all subjects. The results showed that PD patients had significantly lower trunk muscle strength, but more trunk rigidity than controls by 46.6 and 162.8%, respectively (P < 0.001). In bivariate correlation analysis, lumbar spine BMD was significantly related to trunk muscle strength (r = 0.475, P = 0.001), but not trunk rigidity (r = 0.271, P = 0.079). In multiple regression analysis, after adjusting for relevant factors, only trunk muscle strength remained independently associated with lumbar spine BMD, accounting for 10.0% of the variance (R(2) = 0.342, F(5,) (37) = 3.838, P = 0.007). Trunk muscle strength, but not trunk rigidity, is independently associated with lumbar spine BMD in patients with PD. Further randomized controlled studies are required to determine whether trunk muscle strengthening exercise is effective in enhancing lumbar spine BMD.

This study aimed to examine the contribution of balance self-efficacy to walking capacity in patients with Parkinson's disease (PD). Seventy-one patients with PD and 55 healthy subjects completed the study. Walking capacity was quantified by 6-min walk (6MW) test. Perceived balance self-efficacy was assessed by activities-specific balance confidence (ABC) scale. PD-specific motor impairments were determined by Unified PD rating scale (Motor Examination III) and maximum muscle strength of lower extremities. Patients with PD achieved significantly shorter 6MW distance and lower ABC score than control subjects (P < 0.001). In multiple regression analysis, after accounting for basic demographics and PD-specific motor impairments, ABC score remained independently associated with 6MW distance, accounting for 17.1% of the variance (P < 0.001). This is the first study demonstrating that balance self-efficacy is an important and independent determinant of functional walking capacity in patients with PD. Improving balance confidence could be crucial in promoting walking capacity in PD population.

Mak MK, Lau AL, Law FS, Cheung CC, Wong IS. Validation of the Chinese translated Activities-Specific Balance Confidence scale. Objectives To translate contents of the Activities-Specific Balance Confidence (ABC) scale into Chinese (Cantonese), to examine the psychometric properties (internal reliability and validity) of this scale for use with Chinese older adults in Hong Kong, and to determine the level of self-perceived balance confidence of this population. Design A 2-phase exploratory study: formative qualitative research and a cross-sectional survey to establish the psychometric properties of the Chinese translated ABC (ABC-C) scale. Setting Community based. Participants One hundred older community-dwelling subjects. Interventions Not applicable. Main Outcome Measure Measurement of perceived level of confidence in maintaining balance using the ABC-C scale. This instrument contains 16 items on indoor and outdoor activities requiring different levels of balance function. Results Four of the 16 ABC-C scale items had to be modified to achieve content equivalence and cultural relevance to Hong Kong. Final test items of this scale showed high internal consistency with a Cronbach α coefficient of .97. The instrument was found to have excellent test-retest and very good interrater reliability with intraclass coefficients of .99 and .85, respectively. Results of a factor analysis conducted on the scale showed evidence of a coherent 1-domain structure. The mean perceived balance confidence level ± standard deviation of 100 community-dwelling older adults in Hong Kong, performed by using the ABC-C scale, was 71.6±23.7. Conclusions Results of the present study verified that the ABC-C scale is a culturally relevant, valid, and reliable tool for measuring self-perceived balance confidence in Chinese older adults. These were reflected in very good to excellent internal consistency of items, test-retest and interrater reliability, and construct validity shown.

s / Brain Stimulation 8 (2015) 412e427 418 retinopathy this indexwas 86.5+ 5.5 s and 131.7+ 10.2 s respectively. In the presence of cerebellar TMS the VEP amplitude depressionwas less pronounced, and the restoration period of the VEP characteristics shortened to 92,1+ 7,2 s in patients with diabetic retinopathy. Discussion: Hence, gained data revealed that diabetic retinopathy development is linkedtoprolongedVEPlatencyperiod(P100), lowering of the N75-P100 amplitude, as well as to prolongation of the recovery period of the retina’s functional capacity in patients suffering from the second type of diabetes in the presence of photostress. Cerebellar TMS facilitatesa faster recoveryof theretina’s functionalcapacity inresponse to photostress in diabetic patients with retinopathy. It is supposed that antioxidativemechanisms,whichare inducedbycerebellar stimulation in retina, are in charge for the observed therapeutic effects.

We investigated whether preparatory signals, in the form of audiovisual cues, could enhance the performance of sit-to-stand (STS) in Parkinson's disease (PD) patients. Fifteen patients and fifteen control subjects similar in age, gender, weight, and height were examined. All subjects were instructed to carry out STS under self-initiated and cue-initiated conditions. A PEAK Motion Analysis System and two force plates were synchronized to record kinematic and kinetic data. In patients with PD, the addition of audiovisual cues was found to increase hip flexion and knee extension torques and decrease the time-to-peak joint torques, as well as increase peak horizontal and vertical velocities of the body center of mass and decrease the time taken to complete STS. Consequently, the performance of STS in these patients approached that of control subjects. In fact, during cue-initiated STS, no difference was found between the patient and control groups for the time-to-peak of all joint torques, the peak horizontal and vertical velocities, and the time taken to complete STS. Our findings thus demonstrated that audiovisual cues were effective in enhancing STS in patients with PD. These feed-forward signals could have enhanced the defective motor preparatory phase, thus leading to improved performance of the STS task. These findings provide a scientific basis for the use of audiovisual signals to enhance STS performance in patients with PD.

Calculation of joint torques during the rising phase of sit-to-stand motion is in most cases indeterminate, due to the unknown thighs/chair reaction forces in addition to the other sources of uncertainties such as joint positioning and anthropometric data. In the present study we tested the reliability of computation of the joint torques from a five-segment model; we used force plate data of thighs/chair and feet/ground reaction forces, in addition to kinematic measurements. While solving for joint torques before and after seat-off, differences between model solutions and measured data were calculated and minimized using an iterative algorithm for the reestimation of joint positioning and anthropometric properties. The above method was demonstrated for a group of six normal elderly persons.

Objectives. To compare lower limb joint torques during sit-to-stand in normal elderly subjects and people with Parkinson’s disease, using a developed biomechanical model simulating all phases of sit-to-stand. Design. A cross-sectional study utilizing a Parkinsonian and a control group. Background. Subjects with Parkinson’s disease were observed to experience difficulty in performing sit-to-stand. The developed model was used to calculate the lower limb joint torques in normal elderly subjects and subjects with Parkinson’s disease, to delineate possible causes underlying difficulties in initiating sit-to-stand task. Methods. Six normal elderly subjects and seven age-matched subjects with Parkinson’s disease performed five sit-to-stand trials at their self-selected speed. Anthropometric data, two-dimensional kinematic and foot-ground and thigh-chair reactive forces were used to calculate, via inverse dynamics, the joint torques during sit-to-stand in both before and after seat-off phases. The difference between the control and Parkinson’s disease group was analysed using independent t-tests. Results. Both control and Parkinson’s disease groups had a similar joint kinematic pattern, although the Parkinson’s disease group demonstrated a slower angular displacement. The latter subjects produced significantly smaller normalized hip flexion torque and presented a slower torque build-up rate than the able-bodied subjects (P

Patients with Parkinson's disease (PD) are known to manifest slowness in movements. We sought to identify the particular kinematic and kinetic disorders that contribute to the slowness in performing sit-to-stand in these patients. Two inter-related studies were carried out. In the first study, 20 patients with PD and 20 control subjects were instructed to perform sit-to-stand at a natural speed. In the second study, 15 control subjects were instructed to simulate the slower speed of sit-to-stand of the patients identified in the first study. Kinematic and kinetic data were recorded by a PEAK motion analysis system and two force platforms. The results showed that patients with PD generated smaller peak horizontal and vertical velocities during the task. They took a longer time to complete each individual phase as well as the whole movement of sit-to-stand. Patients also produced smaller peak hip flexion and ankle dorsiflexion joint torques and had prolonged time-to-peak torques from sit-to-stand onset. When control subjects simulated the patients' speed of sit-to-stand, there was no difference in all the kinematic and kinetic data between groups. The only exception was that they exhibited a shorter transition time between peak horizontal velocity (flexion phase) and seat-off (extension phase) than the patients. This study demonstrated that the slowness of PD patients during sit-to-stand at a natural speed could be attributed to inadequate peak hip flexion and ankle dorsiflexion torques, a prolonged torque production, as well as a difficulty in switching from the flexion to extension direction during sit-to-stand. As the latter difficulty persisted when the control subjects performed the task at a speed similar to that of the patients, our findings suggest that a fundamental problem of patients with Parkinson's disease could be a switch between movement directions. © 2002 Movement Disorder Society

Objective. To examine the effects of technology-assisted balance and gait training on reducing falls in patients with Parkinson’s disease (PD). Methods. Eligible subjects were randomly allocated to an experimental group given technology-assisted balance and gait training (BAL, n = 26) and an active control group undertaking strengthening exercises (CON, n = 25). The training in each group lasted for 3 months. The number of fallers and fall rate were used as primary outcomes, and single-leg-stance-time, latency of postural response to perturbation, self-selected gait velocity, and stride length as secondary outcomes. Fall incidence was recorded over 15 months after the baseline assessment (Pre). Other tests were performed at Pre, after 3-month intervention (Post3m), at 3 months (Post6m), and 12 months (Post15m) after treatment completion. Results. Forty-five subjects who completed the 3-month training were included in the data analysis. There were fewer fallers in the BAL than in the CON group at Post3m, Post6m, and Post15m ( P < .05). In addition, the BAL group had lower fall rate than the CON group at Post3m and Post6m (incidence rate ratio: 0.111-0.188, P < .05), and marginally so at Post15m (incidence rate ratio: 0.407, P = .057). Compared with the CON subjects, the BAL subjects demonstrated greater reduction in the postural response latency and increase in the stride length against baseline at each assessment interval ( P < .05), and marginally more increases of single-leg-stance-time at Post3m ( P = .064), Post6m ( P = .041) and Post15m ( P = .087). Conclusions. Our positive findings provide evidence for the clinical use of technology-assisted balance and gait training in reducing falls in people with PD.

Objective To examine whether impairment in executive function independently predicts recurrent falls in people with Parkinson's disease (PD). Design Prospective cohort study. Setting University motor control research laboratory. Participants A convenience sample of community-dwelling people with PD (N=144) was recruited from a patient self-help group and movement disorders clinics. Interventions Not applicable. Main Outcome Measures Executive function was assessed with the Mattis Dementia Rating Scale Initiation/Perseveration (MDRS-IP) subtest, and fear of falling (FoF) with the Activities-specific Balance Confidence (ABC) Scale. All participants were followed up for 12 months to record the number of monthly fall events. Results Forty-two people with PD had at least 2 falls during the follow-up period and were classified as recurrent fallers. After accounting for demographic variables and fall history ( P =.001), multiple logistic regression analysis showed that the ABC scores ( P =.014) and MDRS-IP scores ( P =.006) were significantly associated with future recurrent falls among people with PD. The overall accuracy of the prediction was 85.9%. With the use of the significant predictors identified in multiple logistic regression analysis, a prediction model determined by the logistic function was generated: Z=1.544 + .378 (fall history) − .045 (ABC) − .145 (MDRS-IP). Conclusions Impaired executive function is a significant predictor of future recurrent falls in people with PD. Participants with executive dysfunction and greater FoF at baseline had a significantly greater risk of sustaining a recurrent fall within the subsequent 12 months.

To examine whether the Mini-Balance Evaluation Systems Test (Mini-BESTest) independently predicts recurrent falls in people with Parkinson's disease.The study used a longitudinal cohort design.A total of 110 patients with Parkinson's disease completed the study and were included in the final analysis. Most of the patients had moderate disease severity.All subjects were measured to establish a baseline. The tests used were Unified Parkinson's Disease Rating Scale (MDS-UPDRS III), Freezing of Gait Questionnaire, Five-Time-Sit-To-Stand Test, and Mini-BESTest. All patients were followed by telephone interview for 6 months to register the incidence of monthly falls.Twenty-four patients (21.2%) reported more than one fall and were classified as recurrent fallers. Results of the multivariate logistic regression showed that, after adjusting for fall history and MDS-UPDRS III score, the Mini-BESTest score remained a significant predictor of recurrent falls. We further established that a cut-off Mini-BESTest score of 19 had the best sensitivity (79%) for predicting future falls in patients with Parkinson's disease.The results indicate that those with a Mini-BESTest score 19 at baseline had a significantly higher risk of sustaining recurrent falls in the next 6 months. These findings highlight the importance of evaluating dynamic balance ability during fall risk assessment in patients with Parkinson's disease.

Background Previous studies have shown that people with Parkinson disease (PD) have difficulty performing the sit-to-stand task because of mobility and stability-related impairments. Despite its importance, literature on the quantification of dynamic stability control in people with PD during this task is limited. Objective The study objective was to examine differences in dynamic stability control between people with PD and people who were healthy and the extent to which externally cued training could improve such control during the sit-to-stand task in people with PD. Design This was a quasi-experimental controlled trial. Methods The performance of 21 people with PD was compared with that of 12 older adults who dwelled in the community. People with PD were randomly assigned to 2 groups: a group that did not receive training and a group that received audiovisually cued training (3 times per week for 4 weeks) for speeding up performance on the sit-to-stand task. Outcome measures recorded at baseline and after 4 weeks included center-of-mass position, center-of-mass velocity, and stability against either backward or forward balance loss (backward or forward stability) at seat-off and movement termination. Results Compared with people who were healthy, people with PD had greater backward stability resulting from a more anterior center-of-mass position at seat-off. This feature, combined with decreased forward stability at movement termination, increased their risk of forward balance loss at movement termination. After training, people with PD achieved greater backward stability through increased forward center-of-mass velocity at seat-off and reduced the likelihood of forward balance loss at movement termination through a posterior shift in the center-of-mass position. Limitations The study applied stability limits derived from adults who were healthy to people with PD, and the suggested impact on the risk of balance loss and falling is based on these theoretical stability limits. Conclusions For people with PD, postural stability against backward balance loss at task initiation was increased at the expense of possible forward balance loss at task termination. Task-specific training with preparatory audiovisual cues resulted in improved overall dynamic stability against both forward and backward balance loss.

Objective: To examine the effects of repetitive volitional and compensatory step training with preparatory signals on the limits of stability, postural and gait skills, and spatiotemporal gait characteristics in patients with Parkinson’s disease with no falls during the previous 12 months. Design: Randomized clinical trial with assessor blinded to group assignment. Subjects: Twenty-eight patients with Parkinson’s disease with no falls during the previous 12 months. Methods: Eligible patients were randomly assigned to an experimental group, which undertook repetitive step training with preparatory visual cues, or a control group, which undertook lower limb strength training for 4 weeks. Outcome measures included limits of stability test, postural and gait sub-scores from Unified Parkinson’s Disease Rating Scale motor score (UPDRS-PG), and spatiotemporal gait characteristics. All tests were conducted before and after training at patients’ peak medication cycle. Results: The experimental group showed significant improvements in reaction time, movement velocity, and endpoint excursion of limits of stability, as well as UPDRS-PG score and stride length (p < 0.05), compared with the control group. Both groups significantly increased gait velocity ( p < 0.05). Conclusion: Repetitive step training with preparatory cues can enhance limits of stability, postural and gait skills and spatiotemporal gait characteristics in patients with Parkinson’s disease with no falls during the previous 12 months.

Previous studies found that people with Parkinson's disease (PD) walked at a slower speed and with significantly shorter stride length and/or increase in variability of stride length than control subjects. The present study aimed to examine whether difference existed in amplitude and variability of step length between control and PD subjects if they walked at a similar speed.This was a cross-sectional study. Thirteen PD patients and 15 healthy control subjects were instructed to walk at a similar speed on a treadmill under 2 randomized conditions: walking alone (Walk(o)) and walking with digit subtraction of 3 (Walk(calculation)). Amplitude of step length (cm), variability of step length (%), and percent accuracy of the calculation task (%) were recorded and analysed.During both Walk(o) and Walk(calculation), PD patients had significantly shorter step length and larger step length variability than control subjects (p0.05). When a cognitive task was added to walking, PD patients showed a significant decrease in step length without further change in step length variability (p0.05).As reduced step length persisted when the control subjects walked at a speed similar to that of patients, our finding suggests that PD patients had a fundamental problem in regulating the amplitude of step length during walking.

PURPOSE To investigate the performance of reaching and grasping a moving target in children with developmental coordination disorder (DCD). METHODS Sixteen children with DCD and 11 age-matched controls were instructed to reach and grasp a toy car that was sliding down an 8° or 15° slope. Reaction time (RT), movement time (MT), and peak force (PF) were recorded. RESULTS Children with DCD failed 35% of total test trials. Within the successful trials, children with DCD had significantly longer RTs and MTs and generated larger PF than control children (P < .05). When the slope increased from 8° to 15°, both groups of children could adjust MT and PF (P < .01). CONCLUSION Children with DCD were slower and generated larger force to reach and grasp a moving target than their age-matched peers. However, the ability to modify the MT and grip force appeared to be preserved in children with DCD.

The purpose of this paper was to examine the reliability and validity (concurrent and construct) of a newly developed online Chinese version of the Rivermead Behavioral Memory Test (OL-RBMT) and its equivalence with the face-to-face version (FTF-RBMT). The OL-RBMT and FTF-RBMT were administered to 30 subjects with stroke in a two-week interval to establish their test-retest reliability, as well as to compare the two tests' equivalence. The OL-RBMT was further compared with another 30 age- and gender-matched, non-stroke patients to establish its construct validity. Its concurrent validity was established by computing scores with that of the Chinese version of Neurobehavioral Cognitive Status Examination (NCSE or Cognistat). The intra-class correlation for test-retest reliability of the OL-RBMT was 0.94 (P < 0.01). Pearson's correlation coefficients between the subscores of OL-RBMT and FTF-RBMT ranged from 0.84 to 0.93 (P < 0.01). Statistically significant correlation was found between OL-RBMT and NCSE scores (R = 0.797, P < 0.001), as well as in the differences in OL-RBMT scores between the stroke and non-stroke groups (Z = -4.041, P < 0.001). We consider that the reliability and validity of this newly developed online version of RBMT was established. Usability of the OL-RBMT was also discussed.

Objective: To study the influence of physical impairments on hip bone mineral density in women with Parkinson’s disease. Design: Cross-sectional study. Subjects/patients: Thirty-four women with Parkinson’s disease and 30 age-matched healthy controls. Methods: Patients with Parkinson’s disease underwent a hip scan using dual-energy X-ray absorptiometry and total hip bone mineral density values were obtained. Motor Examination III of the Unified Parkinson Disease Rating Scale was used to assess leg tremor, leg agility, leg rigidity and postural stability. In addition, all subjects were evaluated for walking speed, walking endurance, and leg muscle strength. Results: Based on the hip bone mineral density values, 12 patients with Parkinson’s disease (35%) had osteopaenia and another 3 patients (9%) had osteoporosis. Patients with Parkinson’s disease had significantly lower walking veloc ity (p = 0.002), walking endurance (p < 0.001) and leg muscle strength (p = 0.047) than controls. Multiple regression revealed that leg muscle strength alone accounted for 8.8– 10.6% of the variance in hip bone mineral density among patients with Parkinson’s disease, after controlling for body mass index, post-menopausal years, Hoehn and Yahr stage, and postural stability (p < 0.05). Conclusion: Hip bone mineral density is independently associated with leg muscle strength in women with Parkinson’s disease.

The present study aimed to examine whether fear of falling (FoF) could independently predict recurrent falls in people with Parkinson's disease (PD). Seventy patients with PD completed the study. Thirty-two patients had fallen at least once in the previous 12 months. Most of patients with PD had moderate disease severity (Hoehn and Yahr stage III). FoF was assessed by the activities-specific balance confidence (ABC) scale. PD specific motor and balance impairment was determined by Unified PD rating scale (UPDRS). Functional mobility was measured by timed-up-and-go (TUG) test. All patients were followed for 12 months by phone interview to register monthly fall incidence. Results of stepwise discriminant analysis showed that after adjusting for the fall history (F = 32.57, P < 0.001) and UPDRS motor score (F = 25.23, P < 0.001), ABC score (F = 18.84, P < 0.001) remained as a significant predictor of recurrent falls. We further established that a cut-off ABC score of 69 (i.e. 0-100, 0 indicates no confidence and 100 indicates full confidence) demonstrated the best sensitivity (93%) in predicting future falls in PD patients. The results indicate that those with an ABC score

The present study aimed to examine the association of falls with self-perceived balance confidence level, and balance and mobility performance in patients with Parkinson's disease (PD). Forty-nine healthy subjects and 71 subjects with PD completed the study. Among the PD patients, 33 (46%) were fallers and 38 were non-fallers. All subjects were tested with the activities-specific balance confidence scale (ABC), one-leg-stance test (OLS), and timed-up-and-go test (TUG). Results indicated that PD fallers had significantly lower ABC scores, shorter OLS times and longer times to complete TUG than PD non-fallers (P0.05). Having a high ABC score (80) was significantly associated with a lower fall risk, after adjusting for age, gender, and duration of PD, and for depression [odds ratio (OR) = 0.06, P = 0.020]. For performance-based measures of balance and mobility, a longer TUG time (or =16 s) was independently associated with increased risk of falling after controlling for relevant factors (OR = 3.86, P = 0.043); OLS time, however, was not significantly associated with falls. A lower self-perceived balance confidence level and a prolonged time to complete TUG were associated with increased risk of falling in patients with PD. Interventions to improve these modifiable risk factors could be useful in reducing future falls in the PD population and will require further study.

The present study compared kinematic strategies for making sudden directional changes during walking between patients with Parkinson's disease (PwPD) and age-matched controls. Ten PwPD and 10 healthy elderly were visually cued to walk straight or to turn either 30 degrees or 60 degrees to the left or right, at the mid-point of a 9-m walkway. Three-dimensional kinematic data recorded: (1) the onset time of body segments in response to the turning cue, and (2) step width at the first ipsilateral foot contact (IFC(1)) marking the beginning of turn, the subsequent contralateral foot contact (CFC), and the second ipsilateral foot contact (IFC(2)) marking the completion of turn. For both 30 degrees and 60 degrees turns, PwPD had later onset times for lateral foot displacement, and larger time lags between the onset of body CoM and the lateral foot translation than healthy subjects (P0.05). Furthermore, PwPD had a significantly narrower step width than healthy subjects (P0.05). Despite these differences, PwPD and control subjects scaled up turning speed and amplitude similarly for 30 degrees and 60 degrees turns. Our findings suggested that PwPD manifested specific difficulty in modifying their ongoing motor program to switch their locomotion from straight line to sideway direction, but their ability to scale movement speed and amplitude appeared to be preserved.

We examined whether 4 weeks of audio-visual (AV) cued task-specific training could enhance sit-to-stand (STS) and whether the treatment effects could outlast the treatment period by 2 weeks. Fifty-two subjects with PD completed the study. They were randomly allocated to receive 4 weeks of AV cued task-specific training, conventional exercise (Ex), or no treatment (control). Each subject was assessed before, at the end of 2 and 4 weeks of treatment, and 2 weeks after treatment ended. After 2 weeks of training, the AV group significantly increased the peak horizontal velocity (by 13%, P

We aimed to develop an objective measurement to quantify trunk rigidity in patients with Parkinson's disease (PD), and to examine its reliability, validity and sensitivity in differentiating PD patients from control subjects. In Study 1, an isokinetic dynamometer was employed to assess trunk rigidity in 6 PD patients and 6 healthy controls. Passive trunk flexion and extension at 4 angular velocities were applied and resistive torques were recorded. Both work done and resistive peak torques to passive trunk flexion (Torque(PF)) and extension (Torque(PE)) were found to be highly reliable within a 2-day interval in PD patients and control subjects. In Study 2, trunk muscle tone was compared between 15 PD and 15 control subjects. Significantly higher muscle tone, as shown by increases in work done, and in Torque(PF) and Torque(PE )at higher movement speeds, was found in PD patients. Within each subject group, resistive trunk muscle tone was found to increase with increasing velocity of passive movement, but the extent of increase was greater in PD patients. Our results thus suggest that the objective method developed by us was reliable and could differentiate trunk rigidity in PD patients from that of healthy subjects.

Objective : To evaluate whether Parkinsonian patients could modify the speed of a sit-to-stand (STS) task to the same extent as that of healthy subjects. Methods : Twenty Parkinsonian patients and 20 control subjects were instructed to stand up at a natural and fast speed. Kinematic data and kinetic data were recorded. Results : Parkinsonian patients were significantly slower than healthy individuals during STS at a natural speed. When required to perform STS task at a fast speed, these patients could increase both peak horizontal and vertical velocities of the task, by significantly increasing hip and ankle dorsiflexion torques and the rate of torque production, just as the control subjects did. In fact, no difference was found for the percentage changes in both peak velocities and movement time between the two groups, though similar between-group differences during STS at a natural speed still existed at a fast speed. Conclusions : Parkinsonian patients had problems in generating adequate lower limb joint torques and in the rate of torque production when performing STS at a natural speed. However, these patients were capable of increasing the speed of their STS with the same percentage changes as those of healthy subjects. Significance : The capability of Parkinsonian patients for increasing movement speed gives new insights to rehabilitation strategy.

Mak MK, Ng PL. Mediolateral sway in single-leg stance is the best discriminator of balance performance for Tai-Chi practitioners. Arch Phys Med Rehabil 2003;84:683-6. Objectives: To identify a balance measure that can best distinguish Tai-Chi from non-Tai-Chi practitioners and to examine whether longer Tai-Chi practice results in better balance control. Design: Cross-sectional comparative study. Setting: Community. Participants: Nineteen Tai-Chi practitioners (who practiced Tai Chi for 30–45min at least 3/wk for >1y) and 19 healthy subjects with regular exercise habits (who practiced Tai Chi for 30–45min at least 3/wk for >1y). Interventions: Not applicable. Main Outcome Measures: Scores on 2 clinical tests (functional reach, gait) and 1 laboratory test (postural sway). Results: Tai-Chi practitioners had better clinical test scores for functional reach, gait speed, stride length, and sway parameters during single-leg stance ( P Conclusions: Tai-Chi practitioners performed better both in clinical and laboratory tests when compared with subjects who did not practice Tai Chi. More Tai-Chi experience was associated with better postural control.

Question Does adding repetitive transcranial magnetic stimulation (rTMS) to treadmill training modulate cortical excitability and improve walking in people with Parkinson's disease (PD)? Design Randomised controlled trial with blinded outcome assessment. Setting A medical centre in Taiwan. Participants Individuals with Parkinson's disease (Hoehn and Yahr Stage 2-3), and ability to walk independently were key inclusion criteria. Absence of motor evoked potential in response to rTMS, history of seizure, and use of cardiac pacemaker were key exclusion criteria. Randomisation of 22 participants allocated 11 to each of the experimental and control groups. Interventions Both groups underwent 12 treatment sessions over 4 weeks. In each session, the experimental group received rTMS (5 Hz) applied over the leg area of the motor cortex in the hemisphere contralateral to the more affected leg for 6 minutes, immediately followed by 30 minutes of treadmill training. The control group received sham rTMS in addition to the 12 sessions of treadmill training. Outcome measures The primary outcomes were indicators of corticomotor excitability - motor threshold, silent period, short-latency and long-latency intracortical inhibition - measured in both cerebral hemispheres. The secondary outcomes were comfortable and fast walking speeds, and the timed-up-and go test. The outcomes were measured at baseline and after the 4-week intervention period. Results 20 participants completed the study. At the end of the 4-week intervention period, the increase in motor threshold of 3.5% and silent period of 14.0% of the contralateral hemisphere relative to the more affected leg was significantly more in the experimental group than the control group. Significantly more reduction of short-latency intracortical inhibition in the same hemisphere was also found in the experimental group relative to the control group 10.9%. The experimental group also had significantly more improvement than the control group in fast walking speed (by 10.1cm/s) and in the timed up- and-go test (by 2.0 s). No significant differences between the groups were reported in other outcomes. Conclusion Repetitive transcranial magnetic stimulation can enhance the effects on corticomotor inhibition and improvement of walking function induced by treadmill training in patients with Parkinson's disease.

Methods: Nine young healthy individuals completed the study. They were instructed to grip a force transducer with their non-dominant thumb and index finger. Subjects were instructed to reach the target force as accurate and as fast as possible. Feedback about the target force and the time taken to complete each set of exercise was indicated on the computer screen. Subjects were requested to complete 15 sets of exercises, which took about 20 minutes. Outcome measures consisted of purdue pegboard test that recorded the number of pins to be inserted in the pegboard in 30 seconds, tapping test that recorded the number of letter ‘b’ typed on a computer keyboard for 30 seconds, and maximum pinch grip force exerted by thumb and index finger. For the electrophysiological test, transcranial magnetic stimulation (TMS) was used to elicit single pulse to the hemisphere contralateral to stimulate first dorsal interossei (FDI). Motor evoked potential recruitment curve was obtained from stimulator output of 100% to 160%, and the peak MEP amplitude was also recorded.