Botulinum toxin and conservative treatment strategies in people with cervical dystonia: an online survey.

Isolated cervical dystonia is a focal, idiopathic dystonia affecting the neck muscles. Treatment usually consists of botulinum neurotoxin (BoNT) injections into the dystonic muscles. Our aim is to investigate the use of BoNT treatment and conservative treatments by people living with cervical dystonia. An online survey in English was conducted between June and August 2022. Participants were eligible to participate if they were living with cervical dystonia, were over 18 years old and could read and understand English. The survey consisted of demographic questions, characteristics of dystonia, questions relating to BoNT use and the perceived utility of conservative treatments. The data were analysed descriptively, and open-ended questions were grouped into similar topics represented by direct quotes. We received 128 responses from people with cervical dystonia, with an average age of 59 years and 77% women. Most participants (52%) described their cervical dystonia as mild to moderate with an average pain score of 5/10. Eighty-two (64%) participants were having regular BoNT injections, with overall positive perceived effects. Common activities reported to improve the symptoms were the use of heat packs, massage, relaxation, physiotherapy and participation in general exercise. Common coping strategies reported were getting sufficient rest, having the support of friends and family, and remaining engaged in enjoyable hobbies. We found that most participants received regular BoNT injections and that heat packs, exercise, massage, physiotherapy and relaxation were mostly perceived as effective in reducing the symptoms of cervical dystonia.

A cross-sectional study of walking, balance and upper limb assessment scales in people with cervical dystonia.

Cervical dystonia (CD) is a neurological movement disorder causing the neck to move involuntarily away from the neutral position. CD is a network disorder, involving multiple brain areas and, therefore, may impair movement in parts of the body other than the neck. This study used clinical assessments to investigate walking, balance and upper limb function (UL) in people with CD; the reliability of scoring these assessments and examined for relationship between CD severity, usual exercise and clinical assessments. We conducted a prospective observational cohort study of participants with isolated, focal, idiopathic CD. Participants were assessed by experienced physiotherapists and completed three questionnaires and eight clinical assessments of fear of falling, balance confidence, walking, balance, UL function and usual exercise. Results were compared to published data from healthy adults and other neurological populations. Twenty-two people with mild to moderate CD participated. Fear of falling, gross UL function and usual exercise were worse in people with CD compared with healthy adults, while walking, balance and distal UL function were similar to healthy populations. All assessments were reliably performed by physiotherapists, and we found no correlations between the severity of dystonia or usual exercise and performance on the physical assessments. Routine performance of clinical assessment of walking and balance are likely not required in people with mild to moderate CD; however, fear of falling and gross upper limb function should be assessed to determine any problems which may be amenable to therapy.

Fall-related hospitalization in people with Parkinson's disease.

BACKGROUND AND PURPOSE: Falls are common in people with Parkinson's disease (PD) but few data exist on fall-related hospitalizations in this group. This population-based study compared fall-related hospital admissions, injury rates and consequences in people with and without PD, and determined whether PD was an independent predictor of fall-related hospital length of stay. METHODS: This was a retrospective study using probabilistic linkage of hospital data in people aged ≥65 years hospitalized for a fall between 1 July 2005 and 31 December 2013 in New South Wales, Australia. Rates of hospital admissions and injuries per person admitted over the study period were compared between people with and without PD using Poisson or negative binomial regression. Multilevel linear modelling was used to analyse length of stay by clustering individuals and adjusting for possible confounders. RESULTS: There were 342 265 fall-related hospital admissions in people aged ≥65 years during the study period, of which 8487 (2.5%) were for people with PD. Sixty-seven per cent of fall-related PD admissions were associated with injury and 35% were associated with fracture. People with PD had higher rate ratios for fall admissions (1.63, 95% confidence interval 1.59-1.67) and injury (1.47, 95% confidence interval 1.43-1.51) and longer median length of stay [9 (interquartile range 1-27) vs. 6 (interquartile range 1-20) days in people without PD; P < 0.001]. PD remained associated with increased length of stay after controlling for comorbidity, age, sex and injury (P < 0.001). CONCLUSIONS: This study provides important benchmark data for hospitalizations for falls and fall injuries for older people with PD, which may be used to monitor the effect of fall prevention programmes.

Inter-limb coordination in bimanual reach-to-grasp following stroke.

Purpose. To determine the extent to which inter-limb coordination in the execution of unimanual and bimanual tasks was impaired following stroke.Methods. Thirteen stroke survivors aged 55 - 77 years and 13 healthy, neurologically intact participants aged 57 - 86 years performed a unimanual and two bimanual tasks involving the relocation of single and paired objects. Movements were recorded using electromagnetic sensors attached to the wrists and a series of micro switches placed under the objects. Main outcome measures included time to complete components of the tasks; comparison between sides; deviation of the hands from a linear trajectory; coordination of the two sides as indicated by relative phase angle.Results. Stroke survivors took longer to complete the bimanual tasks, but did not deviate from the optimal trajectories more than the healthy participants. Both groups performed unimanual tasks faster than bimanual and stroke participants were only slightly less synchronised when performing bimanual tasks.Conclusions. In conclusion, in a group of stroke patients with reasonable strength, inter-limb coordination was mildly impaired. This impairment in coordination was not due to lateral deviation of the impaired limb.

Abnormal muscle activation characteristics associated with loss of dexterity after stroke.

The aim of this study was to characterise the abnormalities of muscle activation which underlie low dexterity after stroke. A broad definition of dexterity was adopted, where loss of dexterity refers to an inability to coordinate muscle activity in the performance of a motor task (i.e. dexterity was not confined to manual dexterity). EMG of biceps brachii and triceps brachii were monitored from 16 people after stroke and 10 neurologically normal controls as they performed a tracking task requiring coordinated elbow flexion and extension. Weakness could not interfere with performance since the task was designed to require minimal strength. Stroke subjects were assigned to a low (n=10) or high (n=6) dexterity group based on their performance. Spatiotemporal aspects of biceps and triceps EMG were analysed. Low dexterity performance after stroke was characterised by excessive biceps muscle activation (P=0.002) and decreased coupling of muscle activation to target motion (P=0.002). In this study, we could rule out weakness, slowness of muscle activation, excessive co-contraction and spasticity as causes of these abnormalities. Therefore, the loss of dexterity after stroke can be seen as a specific negative impairment which can exist independently of other motor impairments and reflects a loss of skill in generating spatial and temporal muscle activation patterns which conform with environmental demands.

Reduced muscle strength is the major determinant of reduced leg muscle power in Parkinson's disease.

BACKGROUND: Reduced muscle power (speed × strength) is associated with increased fall risk and reduced walking speed in people with Parkinson's disease (PD) as well as in the general older population. This study aimed to determine the relative contribution of motor impairments (bradykinesia, tremor, rigidity and weakness) to reduced leg muscle power in people with PD. METHODS: Eighty-two people with PD were tested while "on" medication. Leg extensor muscle strength and muscle power were measured using pneumatic variable resistance equipment. Lower limb bradykinesia, rigidity and tremor were measured using the Movement Disorders Society-sponsored Unified Parkinson's Disease Rating Scale. Associations between motor impairments and leg muscle power were examined using linear regression. RESULTS: Univariate models revealed that muscle strength (R(2) = 0.84), bradykinesia (R(2) = 0.05) and rigidity (R(2) = 0.05) were significantly associated with leg muscle power, while tremor was not. A multivariate model including bradykinesia, tremor, rigidity, muscle strength, age and gender explained 89% of the variance in leg muscle power. This model revealed reduced muscle strength to be the major determinant of reduced muscle power (ß = 0.7), while bradykinesia was a minor contributor to reduced muscle power (ß = -0.1), even when accounting for age and gender. CONCLUSIONS: The findings that reduced strength and bradykinesia contribute to reduced muscle power in people with PD tested "on" medication suggest that these impairments are potential targets for physical interventions.

Reduced muscle power is associated with slower walking velocity and falls in people with Parkinson's disease.

PURPOSE: Muscle strength (force) and power (force x velocity) are reduced in Parkinson's disease (PD). Reduced muscle power is associated with slower walking velocity and falls in the older population, but these associations in people with PD have not previously been investigated. This study investigated the relationships between leg extensor muscle power and strength with walking speed and past falls in people with PD. PARTICIPANTS AND METHODS: Forty people with mild to moderate PD were assessed. Walking velocity was measured over 10 m and the number of falls the participant reported having in the past 12 months was recorded. Leg extensor muscle power and strength were measured using a Keiser leg press machine. RESULTS: Muscle power explained more than half of the variance (R(2) = 0.54) in walking velocity and remained significantly (p < 0.05) associated with walking velocity in models which included Unified Parkinson's Disease Rating Scale (UPDRS) motor scores. Participants with low muscle power were 6 times more likely to report multiple falls in the past year than those with high muscle power (OR = 6.0, 95% CI 1.1 to 33.3), though this association between falls and power was no longer significant in models which included UPDRS motor scores (p = 0.09). CONCLUSION: Muscle power is a significant determinant of walking velocity in PD even after adjusting for UPDRS motor score. Muscle power training warrants investigation in people with PD.

Slowness to develop force contributes to weakness after stroke.

OBJECTIVE: To examine weakness after stroke, in terms of both level and rate of torque generation. DESIGN: Descriptive. T tests for dependent and independent samples and Pearson's product moment correlation coefficients were performed. SETTING: A rehabilitation unit. PARTICIPANTS: Ten stroke subjects, aged 56 to 81 years, undergoing rehabilitation. Ten neurologically normal subjects aged 55 to 78 years were the controls. OUTCOME MEASURES: Peak isometric elbow flexor and extensor torque and time to 90% peak elbow flexor and extensor torque at 6 weeks and at 25 weeks after stroke. RESULTS: At 6 weeks after stroke, subjects were only half as strong and took two to three times longer to produce torque compared to controls (p < or = .05). By 25 weeks after stroke, significant improvements in peak torque (p < or = .02) and time to 90% peak flexor torque (p < or = .05) were seen so that values were within normal limits. CONCLUSION: Decreased rate of torque development compounds the problem of reduced peak torque, which may have significant implications for stroke patients, especially in situations where muscles are very weak or where force needs to be generated quickly.

Parkinson's disease: an investigation of exercise capacity, respiratory function, and gait.

OBJECTIVE: To evaluate the exercise capacity of subjects with mild to moderate Parkinson's disease and determine whether abnormalities in respiratory function and gait affect exercise capacity. DESIGN: Descriptive. Subjects were categorized according to exercise history, disease severity, and presence/absence of upper airway obstruction. SUBJECTS AND SETTING: Sixteen volunteers with mild to moderate idiopathic Parkinson's disease attended a university research laboratory. MAIN OUTCOME MEASURES: Subjects performed a maximum exercise test on a cycle ergometer, together with respiratory function tests and a walking test. Peak values for oxygen consumption and work rate were recorded for the maximum exercise test. Measures of respiratory function included spirometry, flow-volume loops, lung volumes, and mouth pressures. Velocity, stride length, and cadence were measured for preferred and fast speeds of walking. The values obtained on each of these tests were compared with published predicted age- and gender-matched normal values. RESULTS: Peak oxygen consumptions and peak work loads achieved by subjects with Parkinson's disease were not significantly different from normal values, despite evidence of respiratory and gait abnormalities typical of Parkinson's disease. Exercise category was significantly correlated with percent predicted VO2peak (r = .64, p < .01), with sedentary subjects producing lower scores than exercising subjects. There was no significant correlation between disease severity and percent predicted VO2peak. CONCLUSION: Despite their neurological deficit, individuals with mild to moderate Parkinson's disease have the potential to maintain normal exercise capacity with regular aerobic exercise.

Changes in postural sway and performance of functional tasks during rehabilitation after traumatic brain injury.

OBJECTIVE: To investigate changes in postural sway while standing, walking parameters, and performance of functional tasks during rehabilitation in a group of traumatic brain injury (TBI) patients. DESIGN: Descriptive. SETTING: Inpatient brain injury rehabilitation unit. PARTICIPANTS: Thirteen subjects undergoing rehabilitation after severe TBI. OUTCOME MEASURES: Two assessments were performed, 2 to 6 weeks apart that included the following: postural sway in three stance conditions; temporal and spatial parameters of walking; functional assessments of walking, standing up, reaching while standing, and stair climbing. RESULTS: There were significant reductions in postural sway in all stance conditions (p < .05) and significant increases in velocity of walking (p < .05), stride length (p < .01), and left and right step lengths (p < .01). Performance on all functional tasks improved (p < .05) except for functional reach. There were no significant correlations between changes in postural sway and changes in walking parameters or functional assessments. CONCLUSION: This study demonstrated significant improvements in postural sway, walking parameters, and functional tasks during a relatively short period of rehabilitation after severe TBI. Improvements in standing balance appear to be independent of improvements in walking performance, suggesting that different mechanisms underlie improved control of these tasks.

Muscle length effect on the pendulum test.

OBJECTIVE: An investigation of the effect of the length of knee extensor muscles on the pendulum test. DESIGN: Descriptive. Statistical analysis utilized analysis of variance with planned comparisons. SETTING: Community clubs and a stroke rehabilitation unit. PARTICIPANTS: Twenty subjects aged 54 to 83 yrs, more than 6 weeks after stroke, and 31 healthy subjects aged 60 to 79 yrs. OUTCOME MEASURES: Two tests: pendulum test and knee extensor muscle length test. RESULTS: For both affected and intact legs, stroke subjects had significantly smaller angle of reversal (p < .001), peak angular velocity (p < .001), and maximum passive knee flexion (p < .001) than healthy subjects. When angle of reversal was normalized for passive knee flexion, there were no significant differences between healthy and stroke subjects. There were no significant differences in any variable between the intact and affected legs of the stroke subjects. CONCLUSION: Soft tissue changes, rather than hyperreflexia, may explain the decreased angle of reversal and peak angular velocity in the stroke subjects studied.