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.

Validation of Fear of Falling and Balance Confidence Assessment Scales in Persons With Dystonia.

BACKGROUND AND PURPOSE: Falls are problematic for people living with neurological disorders and a fear of falling can impact on actual falls. Fear of falling is commonly assessed using the Falls Self-Efficacy Scale International (FES-I) or the Activities-specific Balance Confidence (ABC) Scale. These scales can predict risk of falling. We aimed to validate the FES-I and the ABC in persons with dystonia. METHODS: We conducted an online survey of people with dystonia, collecting information on demographics, 6-month falls history, dystonia disability, and the FES-I and ABC scales. Scales were validated for structural validity and internal consistency. We also examined goodness-of-fit, convergent validity, and predictive validity, and determined cutoff scores for predicting falls risk. RESULTS: Survey responses (n = 122) showed that both FES-I and ABC scales have high internal validity and convergent validity with the Functional Disability Questionnaire in persons with dystonia. Each scale examines a single factor, fear of falling (FES-I) and balance confidence (ABC). At least one fall was reported by 39% of participants; the cutoff value for falls risk was found to be 29.5 and 71.3 for the FES-I and the ABC respectively. DISCUSSION AND CONCLUSIONS: The FES-I and the ABC scales are valid scales to examine fear of falling and balance confidence in persons with dystonia. Fear of falling is high and balance confidence is low and both are worse in those with dystonia who have previously fallen.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A182).

Changes in alpha-motoneuron excitability with positions that tension neural tissue.

The slump test assesses the contribution of neural tissue to the referred symptoms associated with spinal pain and musculo-skeletal injuries of the lower limb. The limitation to full range of movement in performing this test has, in the past, been attributed to a mechanical restriction in mobility of neural tissue. Recent literature suggests that the limitation may be caused by protective reflex muscle action. The purpose of this study was to establish whether the slump test was associated with an increase or a decrease in excitability of alpha-motoneurons and, therefore, an alteration in muscle activity at the end of the range of movement of the test. Forty-three normal subjects and eight subjects with abnormal neural tension participated in this study. Changes in alpha-motoneuron excitability in neck flexion, moderate slump, and maximum slump positions were assessed by observing changes in H-reflex recruitment curves. Linear regression analysis on the rising portion of the H-reflex recruitment curve enabled calculation of the dependent variable Hslp for statistical analysis. Normal subjects in the moderate and maximum slump positions demonstrated a significant decrease (p < 0.05) in the slope of the H-reflex recruitment curve. Subjects with abnormal neural tension showed a non-significant increase in slope when in these positions. Subject flexibility had a significant influence on motoneuron excitability in the moderate neural tension position with inflexible subjects demonstrating a significant inhibition of motoneurons. The difference between the flexible or moderately flexible subjects and inflexible subjects was not significant in the maximum neural tension position. These findings have important implications for the rationale for treatment selection and success of treatment outcomes in the clinical setting.

The intercept method: a novel method for establishing consistency of M-wave recruitment curves.

The stability of the M-wave is an important component of experimental H-reflex methodology. Despite this importance, there is inconsistency in H-reflex literature on the most valid method of M-wave stability analysis. Further, there is currently no specific method for establishing the stability of an M-wave recruitment curve across various trials within an experiment. Therefore, the aim of this study was to investigate the most appropriate method of M-wave stability analysis for use with the recruitment curve methodology. Twenty-five healthy subjects participated in the study. Four M-wave recruitment curve recordings were made in various static positions that imposed stretch on the posterior structures of the back and leg. Four methods of post-data collection M-wave stability analysis were compared. Although on visual inspection, there was clear evidence of marked alterations to the M-wave recruitment curves between trials in some subject's data, analysis of variance of the Ms/p and Mmax found no significant difference. Evaluation of the percent deviation in Mmax found nine subjects with greater than ten percent deviation in their maximum M-wave across the four trials. The intercept method that utilises analysis of the 95% confidence interval of the intercept of the M-wave recruitment curve slope, excluded eight subjects that demonstrated variation. Comparison of the percent deviation and the intercept method revealed that the intercept method was the most appropriate method for M-wave stability analysis in conjunction with the recruitment curve methodology.

Manual cervical traction reduces alpha-motoneuron excitability in normal subjects.

The excitability of the Flexor Carpi Radialis alpha-motoneuron pool following manual cervical traction was assessed in twenty asymptomatic subjects, and compared to a hands only intervention. The excitability of the alpha-motoneuron pool was measured indirectly using the Hoffmann (H) reflex. H-reflex recruitment curves were taken to assess the number of alpha-motoneurons (alpha-motoneurons) firing in response to a given incremental increase in stimulation intensity. The rate of rise of the slope of the H-reflex recruitment curve (Hslp) was assessed using linear regression. Following manual cervical traction Hslp was significantly lower than pre-intervention trials. Manual cervical traction, therefore, reduced the excitability of the Flexor Carpi Radialis alpha-motoneuron pool. This effect was mediated by the central nervous system. There was no significant decrease in alpha-motoneuron excitability following the hands only intervention. Hslp was shown to be a more sensitive measure of changes in the H-reflex than the more traditional parameter of Hmax/Mmax ratio and should be used in future studies of this nature.