Background/Objectives: Calf muscle hypertonicity following stroke may impair walking rehabilitation. The aim of this study was to assess botulinum toxin (Dysport^®) in post-stroke calf spasticity. Methods: A prospective, multicentre, double-blind, placebo-controlled, dose-ranging study was performed to evaluate dysport at 500, 1,000 or 1,500 units in 234 stroke patients. They were assessed at 4-week intervals over 12 weeks. Results: The primary outcome measure, 2-min walking distance and stepping rate increased significantly in each group (p < 0.05, paired test), but there was no significant difference between groups (including placebo). Following dysport treatment, there were small but significant (p = 0.0002–0.0188) improvements in calf spasticity, limb pain, and a reduction in the use of walking aids, compared to placebo. Investigators’ and patients’ assessments of overall benefit suggested an advantage for dysport over placebo, but this was not significant. Sixty-eight patients reported 130 adverse events, with similar numbers in each group. The few severe events recorded were not considered to be treatment-related. Conclusion: Dysport resulted in a significant reduction in muscle tone, limb pain and dependence on walking aids. The greatest benefits were in patients receiving dysport 1,500 units, but 1,000 units also had significant effects. Dysport 500 units resulted in some improvements. Since few adverse events were reported, this therapy is considered safe and may be a useful treatment in post-stroke rehabilitation of the leg. Possible reasons why functional improvements in gait parameters were not observed are also discussed.

Botulinum neurotoxin is the therapy of choice for all forms of cervical dystonia (CD), but treatment regimens still vary considerably. The interpretation of treatment outcome is mainly based on the clinical experience and on the scientific value of the rating scales applied. The aim of this review is to describe the historical development of rating scales for the assessment of CD and to provide an appraisal of their advantages and drawbacks. The Tsui score and the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) have been widely employed in numerous clinical studies as specific instruments for CD. The obvious advantage of the Tsui score is its simplicity so that it can be easily implemented in clinical routine. The TWSTRS allows a more sophisticated assessment of functional features of CD, but only the Tsui score includes a rating for tremor. Other benefits of the TWSTRS are the disability and pain subscales, but despite its value in clinical trials, it might be too complex for routine clinical practice. None of the rating scales used at present has been rigorously tested for responsiveness to detect significant changes in clinical status after therapeutic interventions. Moreover, clinical data support a new classification of CD leading to a differentiation between head and neck subtypes. As the current rating scales are not able to cover all these aspects of the disorder, further research is needed to develop a valid and reliable instrument which considers the most current classification of CD.

Botulinum toxin has long been known for its paralytic effects on the human voluntary musculature via inhibition of acetylcholine release at neuromuscular junctions. Its original clinical use for the treatment of strabismus has expanded significantly to include neurological conditions related to muscle hyperactivity and/or spasticity (e.g., dystonia, spasticity, tics, tremor, dysphonia). Recently, botulinum toxin has been shown to impact autonomic disorders by acting at acceptors on glands and smooth muscle, and consequently it has been used in the management of a number of other conditions including hypersecretory disorders, pain syndromes, detrusor sphinchter dyssenergia or overactivity and gastointestinal smooth muscle/sphincter spasm; it may also reduce pain in patients for whom it is used to treat these and other primary conditions. This article will review the pharmacology and formulations of botulinum toxins as well as data from clinical trials demonstrating their efficacy for numerous conditions based on their effects on cholinergic synapses outside the motor nervous system.

ObjectivesFew studies have investigated the injection patterns for botulinum toxin type A for the treatment of heterogeneous forms of cervical dystonia (CD). This large, prospective, open-label, multicentre study aimed to evaluate the effectiveness and safety of 500 U botulinum toxin A for the initial treatment according to a standardised algorithm of the two most frequent forms of CD, predominantly torticollis and laterocollis.DesignPatients (aged ≥18 years) with CD not previously treated with botulinum neurotoxin therapy were given one treatment with 500 U Dysport, according to a defined intramuscular injection algorithm based on clinical assessment of direction of head deviation, occurrence of shoulder elevation, occurrence of tremor (all evaluated using the Tsui rating scale) and hypertrophy of the sternocleidomastoid muscle.ResultsIn this study, 516 patients were enrolled, the majority of whom (95.0%) completed treatment. Most patients had torticollis (78.1%). At week 4, mean Tsui scores had significantly decreased by −4.01, −3.76 and −4.09 points in the total, torticollis and laterocollis populations, respectively. Symptom improvement was equally effective between groups. Tsui scores remained significantly below baseline at week 12 in both groups. Treatment was well tolerated; the most frequent adverse events were muscular weakness (13.8%), dysphagia (9.9%) and neck pain (6.6%).ConclusionsDysport 500 U is effective and well tolerated for the de novo management of a range of heterogeneous forms of CD, when using a standardised regimen that allows tailored dosing based on individual symptom assessment.Clinical trials information(NCT00447772; clinicaltrials.gov)

The pathophysiology of cervical dystonia is not completely understood. Current concepts of the pathophysiology propose that it is a network disorder involving the basal ganglia, cerebellum and sensorimotor cortex. These structures are primarily concerned with sensorimotor control but are also involved in non-motor functioning such as the processing of information related to the chemical senses. This overlap lets us hypothesize a link between cervical dystonia and altered sense of smell and taste. To prove this hypothesis and to contribute to the better understanding of cervical dystonia, we assessed olfactory and gustatory functioning in 40 adults with idiopathic cervical dystonia and 40 healthy controls. The Sniffin Sticks were used to assess odor threshold, discrimination and identification. Furthermore, the Taste Strips were applied to assess the combined taste score. Motor and non-motor deficits of cervical dystonia including neuropsychological and psychiatric alterations were assessed as cofactors for regression analyses. We found that cervical dystonia subjects had lower scores than healthy controls for odor threshold (5.8 ± 2.4 versus 8.0 ± 3.2; p = 0.001), odor identification (11.7 ± 2.3 versus 13.1 ± 1.3; p = 0.001) and the combined taste score (9.5 ± 2.2 versus 11.7 ± 2.7; p < 0.001), while no difference was found in odor discrimination (12.0 ± 2.5 versus 12.9 ± 1.8; p = 0.097). Regression analysis suggests that age is the main predictor for olfactory decline in subjects with cervical dystonia. Moreover, performance in the Montreal Cognitive Assessment is a predictor for gustatory decline in cervical dystonia subjects. Findings propose that cervical dystonia is associated with diminished olfactory and gustatory functioning.