Prevalence of spontaneous movement disorders (dyskinesia, parkinsonism, akathisia and dystonia) in never-treated patients with chronic and first-episode psychosis: a systematic review and meta-analysis.

BACKGROUND: The aim of this systematic review and meta-analysis is to evaluate and compare the prevalence rates of spontaneous movement disorders (SMDs), including dyskinesia, parkinsonism, akathisia and dystonia, in antipsychotic-naïve individuals with chronic psychosis and first-episode psychosis (FEP) and gain a more nuanced understanding of factors influencing their presence. METHODS: Several literature databases were systematically searched and screened based on predetermined eligibility criteria. Included articles underwent risk of bias assessment. The prevalence rates of SMDs were calculated using a random-effects model. RESULTS: Out of 711 articles screened, 27 were included in this meta-analysis. The pooled prevalence of spontaneous dyskinesia was 7% (3% FEP and 17% chronic schizophrenia) across 24 studies (95% CI 3 to 11; I2=94%, p<0.01) and 15% for spontaneous parkinsonism (14% FEP and 19% chronic schizophrenia) in 21 studies (95% CI 12 to 20; I2=81%, p<0.01). A meta-regression analysis found a significant positive correlation between age (p<0.05) and duration of untreated psychosis (DUP) (p<0.05) with dyskinesia but not parkinsonism prevalence. Akathisia and dystonia appear to be both less studied and less frequent in occurrence with a pooled prevalence of 4% (95% CI: 3 to 6; I2=0%, p=0.65) for akathisia in eight studies and a mean prevalence of 6% (range 0%-16%) for dystonia in five studies. CONCLUSION: The presence of varying degrees of neurodysfunction in antipsychotic-naïve patients with schizophrenia underscores the need for individualised treatment approaches that consider each patient's unique predisposition and neuromotor profile. Further research is warranted into the role of specific SMDs and risk factors including sex, race and diagnostic variations. PROSPERO REGISTRATION NUMBER: CRD42024501951.

A comprehensive review of scapulothoracic abnormal motion (STAM): evaluation, classification, and treatment strategies.

The term "dyskinesia" has often been used interchangeably with "winging," leading to ambiguity in the literature. To address this, the broader term "scapulothoracic abnormal motion (STAM)" was introduced to describe any abnormal position or movement of the scapula on the chest, resulting in pain and dysfunction. Scapulothoracic abnormal motion has a wide range of causes, including musculoskeletal imbalances such as pectoralis minor hyperactivity, neurological impairments such as long thoracic nerve palsy, and genetic conditions like facioscapulohumeral muscular dystrophy (FSHD). This review aims to identify the different causes and classifications of STAM and to propose a detailed treatment algorithm specifically designed to manage these conditions effectively.

COVID-19 vaccination and involuntary movements: A longitudinal panel study.

OBJECTIVE: Despite high COVID-19 vaccination rates in many populations, concerns persist about potential adverse events, including concerns about involuntary movements. While case studies have shown occurrences of involuntary movements following COVID-19 vaccination, no systematic studies have explored this association. Our study aims to investigate the relationship between COVID-19 vaccination and involuntary movements. METHODS: This study employs a longitudinal panel design. The study population consists of 165,834 responses from a total of 97,537 unique individuals sourced from the BiCoVac cohort, which is a randomly sampled cohort of Danish individuals aged 16 to 65. Data were collected through a combination of questionnaires and national registers, and analyses were conducted using mixed effects logistic regression. RESULTS: Vaccinated individuals had lower odds of reporting involuntary movements compared to non-vaccinated individuals. Although adjustments attenuated the results, a consistent pattern of lower odds was observed among the vaccinated individuals. The strongest association for the first dose was observed in individuals who received the vaccine within the last 4 weeks before reporting symptoms (OR = 0.72 (0.60; 0.85)). For the second dose, the strongest association was found in individuals who received the second vaccine dose more than 4 weeks before reporting symptoms (OR = 0.77 (0.65; 0.91)). CONCLUSION: The results of the study do not indicate involuntary movements as an adverse reaction to the COVID-19 vaccine. These findings support the safety profile of the COVID-19 vaccine concerning involuntary movements and contribute to enhancing public trust in vaccination programs.

Comparing shoulder proprioception, upper extremity dynamic stability, and hand grip strength in overhead athletes with and without scapular dyskinesis.

INTRODUCTION: Scapular dyskinesis is prevalent among asymptomatic athletes, particularly those involved in overhead activities, and can significantly impact their neuromuscular control. These changes may impair upper extremity function and strength, elevating the risk of injury. Therefore, it is imperative to investigate how scapular dyskinesis affects shoulder proprioception, upper extremity dynamic stability, and hand grip strength in overhead athletes. This study compared these parameters between overhead athletes with and without scapular dyskinesis. METHODS: The study included twenty asymptomatic professional overhead athletes with scapular dyskinesis and twenty without scapular dyskinesis, identified using the lateral scapular slide test. In this cross-sectional study, shoulder active joint position sense, serving as shoulder proprioception, was measured using an isokinetic dynamometer. Upper extremity dynamic stability and hand grip strength were evaluated using an upper quarter modified star excursion balance test (UQ-mSEBT) and a handheld dynamometer. RESULTS: The study found that the shoulder active joint position sense was significantly lower in the scapular dyskinesis group compared to the group without scapular dyskinesis (PExternal Rotation = 0.003, PInternal Rotation < 0.001, and PForward Flexion = 0.002). However, the two groups had no significant differences in UQ-mSEBT and hand grip strength scores. CONCLUSIONS: The results showed that scapular dyskinesis could affect the sense of shoulder active joint position among asymptomatic overhead athletes. However, it did not affect their upper extremity dynamic stability and hand grip strength.

Acupuncture combined with mirror therapy for post-stroke dyskinesia: A meta-analysis and systematic review.

BACKGROUND: Dyskinesia is one of the most common complications of stroke. Acupuncture therapy (AT) and mirror therapy (MT) are promising rehabilitation measures for the treatment of post-stroke dyskinesia. Although some studies suggested that AT and MT are effective and safe for dyskinesia, the effects, and safety remain uncertain due to lacking strong evidence. The purpose of this study is to investigate the efficacy and safety of AT combined with MT in the treatment of post-stroke dyskinesia. METHODS: We searched the following databases: PubMed, Web of Science, Cochrane Library, EMBASE, Medline, China Knowledge Network, WANFANG, and China Biomedical Literature Database, from inception to 1 January 2023 to identify eligible studies. Total effective rate, the Fugl-Meyer assessment scale (FMA) upper and lower limb scores, modified Barthel index scores, Berg balance scale, modified Ashworth scale, and adverse reactions were adopted as outcome indicators. The Grading of Recommendations Assessment Development and Evaluation system was used by 2 independent reviewers to assess the quality of evidence for the outcome indicators included in the study. The statistical analysis was conducted by RevMan V.5.4 software. RESULTS: A total of 24 randomized controlled studies included 2133 patients with post-stroke dyskinesia were included. The total effective rate of AT combined with MT was more advantageous in the treatment of post-stroke dyskinesia (relative risk = 1.31, 95% confidence interval [CI] [1.22-1.42], Z = 6.96, P < .0001). AT combined with MT was more advantageous for FMA upper limb score (mean difference [MD] = 6.67, 95% CI [5.21-8.13], Z = 8.97, P < .00001) and FMA lower limb score (MD = 3.72, 95% CI [2.81-4.63], Z = 7.98, P < .00001). Meta-analysis showed that AT combined with MT for post-stroke dyskinesia had a more advantageous modified Barthel index score (MD = 9.51, 95% CI [7.44-11.58], Z = 9.01, P < .00001). CONCLUSION: AT combined with MT is effective in improving motor function and daily living ability of patients, especially in improving muscle spasms. However, these results should be regarded with caution given the low quality of evidence for the evaluation results.

Scapular dyskinesis and overhead athletes: A systematic review of electromyography studies.

OBJECTIVE: Understanding how the main scapular muscles behave in overhead athletes with scapular dyskinesis (SD). DESIGN: Systematic Review. SETTING: Electronic searches were performed in Pubmed (MedLine), Embase, CINAHL, and SPORTDiscus databases. PARTICIPANTS: Overhead athletes with SD. MAIN OUTCOME MEASURES: Electromyographic activity of the upper (UT), middle (MT), and lower (LT) trapezius, and serratus anterior (SA). RESULTS: Eight studies were included in this review. The UT activity showed a tended to increase its activity mainly during tasks over 90° compared to 45°. SA activity had similar behavior, mainly during isometric tasks. The MT also increased its activity mainly in tasks with overhead angulations when compared to lower angulations. The LT activation tended to decrease its EMG activity at angulations below 60° in overhead athletes with SD. CONCLUSIONS: The EMG behaviour of UT and SA for non-athletes appears to differ from what has already been described in the literature. The MT seems to be the most neglected muscle for scapular stabilization in overhead athletes with SD. The decrease in LT activity suggests that this may have implications for the performance of these athletes.

Neural Drive and Motor Unit Characteristics of the Serratus Anterior in Individuals With Scapular Dyskinesis.

OBJECTIVE: Scapular dyskinesis is one of the causes of shoulder disorders and involves muscle weakness in the serratus anterior. This study investigated whether motor unit (MU) recruitment and firing property, which are important for muscle exertion, have altered in serratus anterior of the individuals with scapular dyskinesis. METHODS: Asymptomatic adults with (SD) and without (control) scapular dyskinesis were analyzed. Surface electromyography (sEMG) waveforms were collected at submaximal voluntary contraction of the serratus anterior. The sEMG waveform was decomposed into MU action potential amplitude (MUAPAMP), mean firing rate (MFR), and recruitment threshold. MUs were divided into low, moderate, and high thresholds, and MU recruitment and firing properties of the groups were compared. RESULTS: High-threshold MUAPAMP was significantly smaller in the SD group than in the control group. The control group also exhibited recruitment properties that reflected the size principle, however, the SD group did not. Furthermore, the SD group had a lower MFR than the control group. CONCLUSIONS: Individuals with scapular dyskinesis exhibit altered MU recruitment properties and lower firing rates of the serratus anterior; this may be detrimental to muscle performance. Thus, it may be necessary to improve the neural drive of the serratus anterior when correcting scapular dyskinesis.

Breaking the operator variability in Kibler's scapular dyskinesis assessment.

INTRODUCTION: Alterations of scapular kinematics are generically reported as scapular dyskinesis (SD), and are a nonspecific response to various shoulder pathologies. The most widely used classification is Kibler's (K), which is, however, characterized by poor sensitivity. To overcome this limit, using a 3D motion analysis system, we identified a specific pattern for each type of SD according to Kibler. MATERIALS AND METHODS: We analyzed 34 patients with a total of 68 shoulders who came to our observation for shoulder pain. All patients underwent clinical examination, video-recording and motion analysis with SHoW Motion 3D kinematic tracking system (SM). Three independent observers classified SD into K types I, II and III. Only patients with concordant classification among the 3 operators were studied to identify a characteristic graphic pattern by type of SD. RESULTS: Typical patterns emerged from the examination with SM. K. type 1 consists of decreased or reversed posterior tilt and increased protraction in flexion-extension (FE) in early degrees of motion. K. type 2 consists of increased protraction and marked reversal of lateral rotation in abduction-adduction (Ab-Ad) in early degrees of movement. K. type 3 has been subdivided into two subgroups: K. type 3-A, composed of patients with massive rotator cuff lesions, shows an increase in all scapular movements in both FE and Ab-Ad. K. type 3-B, composed of patients with scapular stiffness and/or impingement, presents a slight increase in posterior tilt and lateral rotation in the final grades of FE and Ab-Ad. CONCLUSIONS: The SM system allows reproducible dynamic analyses with low intra- and intra- operator variability. In our study, we demonstrated its applicability in the classification of SD. It also provides an objective and quantitative assessment of motor pattern alteration that is essential in the follow-up of patients to evaluate the effectiveness of rehabilitation and/or surgical treatment. LEVEL OF EVIDENCE 3: According to "The Oxford 2011 Levels of Evidence".

Hemichorea-hemiballismus due to diabetic striatopathy a serious complication of uncontrolled diabetes.

We report the case of a man in his mid-80s with diabetes mellitus who presented to the emergency department with a 1-day history of right-sided choreiform movements and falls. Laboratory tests revealed blood glucose of 597 mg/dL. Non-contrast CT imaging of his head demonstrated a faint hyperdensity involving the left lentiform nucleus and brain MRI showed a hyperintensity in the left basal ganglia on T1-weighted images. These lesions are typical of diabetic striatopathy. Symptoms of hemichorea/hemiballismus did not resolve with glycaemic control and several pharmacological agents were tried with eventual improvement with risperidone. He was discharged to a rehabilitation facility and had mild persistent arm chorea at 6-month follow-up.

Strength and activity of the protractor and retractor muscles of the asymptomatic dyskinetic scapula.

The role of scapular dyskinesis as a risk factor of shoulder injury has been largely discussed. However, most studies have focused on symptomatic patients and less is known on the asymptomatic dyskinetic scapula. Removing the confounding effects of the pathologies could contribute to better characterize the scapula dyskinesis. As muscle properties (strength, fatigue, nerve injury …) have been identified as causative factors of scapular dyskinesis, this study focuses specifically on characterizing the protractor and retractor muscles of the dyskinetic scapula. Thirteen asymptomatic dyskinetic volunteers were compared to eleven asymptomatic non-dyskinetic control volunteers. Muscle characteristics were evaluated in terms of maximal strength, fatigue resistance and electromyographic activity during a functional closed-chained task. The results did not identify kinematic or muscle activity significant differences between the dyskinetic and the control group even in fatigue conditions. However, the results demonstrated that protractors vs. retractors fatigue resistance ratios were imbalanced (<0.8) in the dyskinetic group and significantly lower than in the non-dyskinetic one. Our study suggests that that strength imbalances are not necessarily related to the presence of pain at the shoulder joint. These results demonstrated the importance to complete the clinical assessments of the scapula with strength evaluations even for asymptomatic sport practitioners.

Implication of regional selectivity of dopamine deficits in impaired suppressing of involuntary movements in Parkinson's disease.

To improve the initiation and speed of intended action, one of the crucial mechanisms is suppressing unwanted movements that interfere with goal-directed behavior, which is observed relatively aberrant in Parkinson's disease patients. Recent research has highlighted that dopamine deficits in Parkinson's disease predominantly occur in the caudal lateral part of the substantia nigra pars compacta (SNc) in human patients. We previously found two parallel circuits within the basal ganglia, primarily divided into circuits mediated by the rostral medial part and caudal lateral part of the SNc dopamine neurons. We have further discovered that the indirect pathway in caudal basal ganglia circuits, facilitated by the caudal lateral part of the SNc dopamine neurons, plays a critical role in suppressing unnecessary involuntary movements when animals perform voluntary goal-directed actions. We thus explored recent research in humans and non-human primates focusing on the distinct functions and networks of the caudal lateral part of the SNc dopamine neurons to elucidate the mechanisms involved in the impairment of suppressing involuntary movements in Parkinson's disease patients.

Motor Complications in Parkinson's Disease: Results from 3343 Patients Followed for up to 12 Years.

BACKGROUND: Motor complications are well recognized in Parkinson's disease (PD), but their reported prevalence varies and functional impact has not been well studied. OBJECTIVES: To quantify the presence, severity, impact and associated factors for motor complications in PD. METHODS: Analysis of three large prospective cohort studies of recent-onset PD patients followed for up to 12 years. The MDS-UPDRS part 4 assessed motor complications and multivariable logistic regression tested for associations. Genetic risk score (GRS) for Parkinson's was calculated from 79 single nucleotide polymorphisms. RESULTS: 3343 cases were included (64.7% male). Off periods affected 35.0% (95% CI 33.0, 37.0) at 4-6 years and 59.0% (55.6, 62.3) at 8-10 years. Dyskinesia affected 18.5% (95% CI 16.9, 20.2) at 4-6 years and 42.1% (38.7, 45.5) at 8-10 years. Dystonia affected 13.4% (12.1, 14.9) at 4-6 years and 22.8% (20.1, 25.9) at 8-10 years. Off periods consistently caused greater functional impact than dyskinesia. Motor complications were more common among those with higher drug doses, younger age at diagnosis, female gender, and greater dopaminergic responsiveness (in challenge tests), with associations emerging 2-4 years post-diagnosis. Higher Parkinson's GRS was associated with early dyskinesia (0.026 ≤ P ≤ 0.050 from 2 to 6 years). CONCLUSIONS: Off periods are more common and cause greater functional impairment than dyskinesia. We confirm previously reported associations between motor complications with several demographic and medication factors. Greater dopaminergic responsiveness and a higher genetic risk score are two novel and significant independent risk factors for the development of motor complications.

Combined thalamic and pallidal deep brain stimulation in diabetic hemiballism/hemichorea.

Hemiballism/hemichorea (HH) is a hyperkinetic movement disorder observed mostly in older adults with cerebrovascular diseases. Although the symptoms improve without any treatment, lesioning or DBS (deep brain stimulation) may be rarely required to provide symptomatic relief for patients with severe involuntary movements. HH is a rare complication of uncontrolled diabetes. There are only a few reported cases of diabetic HH that have been surgically treated. Thus, herein, we have reported the case of a 75-year-old female with type-II diabetes mellitus that presented with disabling involuntary limb movements of the left side, despite being treated conservatively for six months. DBS targeting the globus pallidus internus (GPi) and ventral intermediate (Vim) thalamic nucleus was performed. Complete resolution of symptoms was achieved with a combined stimulation of the thalamic Vim nucleus (at 1.7 mA) and GPi (at 2.4 mA). The combined stimulation of the Vim nucleus and GPi effectively resolved the diabetes-induced HH symptoms in our patient. Thus, although certain conclusions cannot be drawn due to the rarity of the surgically treated patients with HH, the combined stimulation is a novel treatment option for resistant HH.

Botulinum neurotoxin as early treatment in acute-onset lesional hemiballism.

BACKGROUND: Hemiballism (HB) and hemichorea (HC) are the most frequent secondary movement disorders, usually caused by cerebrovascular diseases. In only a minority of cases, these involuntary movements are not self-limited, and they may severely compromise patients' quality of life, so that symptomatic treatments are required. Typical and atypical neuroleptics as well as tetrabenazine are considered therapies of choice. However, anecdotal reports of antiseizures medications and botulinum neurotoxin injection effectiveness have been described. METHODS: We described a case of severely disabling acute-onset lesional HB/HC, where high dosage of first- and second-line therapies was contraindicated due to patient's comorbidities. RESULTS: After botulin neurotoxin (BoNT) injections in his left upper limb muscles (biceps brachii, triceps brachii, teres major, and deltoid), the patient experienced gradual reduction of hyperkinetic movements. The gradual discontinuation of topiramate (TPM) did not worsen the clinical picture. DISCUSSION: The reduction of hyperkinetic movements led to rhabdomyolysis resolution as well as cutaneous injuries healing with renal function improvement, so that the patient was able to be eligible for rehabilitation, which was prevented by HB/HC itself. The clinical improvement was consistent with BoNT pharmacokinetic. The administration of BoNT early after the onset of lesional HB/HC remarkably modified the clinical management and drove toward comorbidities resolution and rehabilitation. CONCLUSION: The present case highlights the effectiveness of unconventional therapeutic options in disabling acute onset lesional HB/HC when first-line therapies are contraindicated. Particularly, this report may encourage BoNT application in the early stage of movement disorder emergencies.

Hyperglycemia-induced hemichorea-hemiballismus syndrome - a systematic review.

Nonketotic hyperglycemia may occur as a cause of chorea in patients with chronic decompensated diabetes. Because it is rare and consequently poorly studied, diagnosis and treatment can be delayed. Therefore, our objective was to summarize clinical and radiological features, as well as treatments performed, from previously reported cases to facilitate adequate management in clinical practice. We searched MEDLINE/PubMed, EMBASE, Cochrane, CINAHL, Web of Science, Scopus, and LILACS databases for studies published before April 23, 2021. We included case reports and case series of adults (aged ≥ 18 years) that described hyperglycemic chorea with measurement ofglycated hemoglobin (HbA1c) and cranial magnetic resonance imaging (MRI). Studies were excluded if participants were pregnant women, aged < 18 years, and had no description of chorea and/or physical examination. We found 121 studies that met the inclusion criteria, for a total of 214 cases. The majority of the included studies were published in Asia (67.3%). Most patients were women(65.3%) aged > 65 years (67.3%). Almost all patients had decompensated diabetes upon arrival at the emergency department (97.2%). The most common MRI finding was abnormalities of the basal ganglia (89.2%). There was no difference in patient recovery between treatment with insulin alone and in combination with other medications. Although rare, hyperglycemic chorea is a reversible cause of this syndrome; therefore, hyperglycemia should always be considered in these cases.

Assessment and Treatment of Abnormal Involuntary Movements: A Clinically Focused Narrative Review.

LEARNING OBJECTIVES: After participating in this CME activity, the psychiatrist should be better able to:• Categorize and describe different types of abnormal involuntary movements (AIMs).• Identify assessment tools and treatment options for AIMs. ABSTRACT: Abnormal involuntary movements (AIMs) comprise a diverse group of movement disorders characterized by uncontrolled and unintended movements (e.g., tremors, tics, dystonia). AIMs can occur at any stage of life and pose significant challenges for clinicians. It is difficult to determine their underlying causes due to the complex neurobiological mechanisms involved. Therefore, it is crucial to quantify the severity and progression of AIMs using well-validated measurement scales, such as the Abnormal Involuntary Movement Scale (AIMS). By employing reliable assessment approaches, clinicians can objectively evaluate the motoric manifestations of AIMs and track them over time. Treatment of AIMs varies depending on their nature and etiology. While AIMs often respond to treatment, serious side effects can undermine treatment efficacy. In this clinically focused narrative review, we categorize different types of AIMs and discuss their neurobiological aspects. Further, we emphasize the importance of using well-validated measurement scales for accurate assessment and discuss available treatment modalities that target the specific AIMs manifestations. Additionally, we cover the need for comprehensive care to address the multifaceted nature of AIMs, accounting for their physical manifestations as well as their psychological, social, and functional toll on patients. By embracing a multidisciplinary approach, health care professionals can provide patient-centered care that promotes overall well-being and enhances the lives of patients coping with AIMs. Regular follow-up assessments are necessary to monitor treatment response, adjust medications when needed, and provide ongoing support for individuals affected by AIMs.

Flapping Tremor: Unraveling Asterixis-A Narrative Review.

Asterixis is a subtype of negative myoclonus characterized by brief, arrhythmic lapses of sustained posture due to involuntary pauses in muscle contraction. We performed a narrative review to characterize further asterixis regarding nomenclature, historical aspects, etiology, pathophysiology, classification, diagnosis, and treatment. Asterixis has been classically used as a synonym for negative myoclonus across the literature and in previous articles. However, it is important to distinguish asterixis from other subtypes of negative myoclonus, for example, epileptic negative myoclonus, because management could change. Asterixis is not specific to any pathophysiological process, but it is more commonly reported in hepatic encephalopathy, renal and respiratory failure, cerebrovascular diseases, as well as associated with drugs that could potentially lead to hyperammonemia, such as valproic acid, carbamazepine, and phenytoin. Asterixis is usually asymptomatic and not spontaneously reported by patients. This highlights the importance of actively searching for this sign in the physical exam of encephalopathic patients because it could indicate an underlying toxic or metabolic cause. Asterixis is usually reversible upon treatment of the underlying cause.

[A Review of Neurological Disorders Caused by Hormonal Abnormalities].

Endocrine dysfunction can considerably impact the nervous system. Various nonspecific neurological symptoms can manifest, including headache, muscle weakness, involuntary movements, and impaired consciousness. Because of their lack of specificity, endocrine abnormalities underlying neurological symptoms may not be recognized and making the diagnosis may be challenging. It is essential that clinicians not overlook endocrine disorders when diagnosing neurological symptoms, as prompt and appropriate treatment, such as hormone replacement therapy, can improve a patient's general condition and neurological symptoms.