Hands-On Sports Medicine Training for Residents

In brief: Primary care sports medicine is a rapidly growing field of interest; however, there are relatively few training programs in this field. The author describes the development of a one-month training program at the University of California, Davis, Medical Center. The education strategies used in the program include clinical teaching (50%), on-the- field education (20%), experiential learning (20%), and didactic instruction (10%). The most innovative part of the program is the experiential learning component, through which students learn basic sports medicine skills by actively participating in sports, exercises, strength training, and a fitness program.     

Effect of lead trajectory on the response of essential head tremor to deep brain stimulation

BackgroundEssential tremor (ET) is one of the most common movement disorders. Normally ET affects the distal upper extremities, but it can also be accompanied by midline symptoms. Ventralis intermedius (VIM) thalamic deep brain stimulation (DBS) has been shown to be effective in reducing hand tremor, but its effects on head tremor have been inconsistent.MethodsTwenty-nine DBS patients with a diagnosis of ET met inclusion criteria. All implantations targeted VIM. The factors examined included age, gender, disease duration, presence or absence of head tremor, handedness, and the Fahn-Tolosa-Marin rating scale (TRS). This analysis specifically focused on TRS head tremor sub-scores at baseline, 6 months and 12 months post-DBS. Additionally, DBS lead entry angles were examined.ResultsTwenty-three ET patients underwent unilateral DBS and six underwent staged bilateral DBS. At both 6 and 12 months following DBS, stimulation resulted in diminished head tremor (ON vs OFF; p < 0.0001). The most important predictor of head tremor suppression was the entry angle of the DBS lead in the sagittal projection relative to the AC–PC axial plane (AC–PC angle). Head tremor reduction was greater among more vertical AC–PC angles.ConclusionA more vertical AC–PC angle of the DBS lead trajectory was associated with improved head tremor suppression. Further studies will be necessary to confirm this potentially important finding.     

The effects of antihistamines with varying anticholinergic properties on voluntary and involuntary movement

ObjectiveRecent evidence indicates that antihistamines can affect movement, which is most likely due to altered neurotransmission in cholinergic and histaminergic pathways. The purpose of this study was to determine if antihistamines with varying anticholinergic properties differentially affect voluntary and involuntary movement control.MethodsEleven healthy subjects were enlisted into a human double blind, placebo-controlled, five-way crossover study. Drowsiness, reaction time, and physiological tremor were examined 1-, 2-, and 3-hr post-ingestion of antihistamines with known anticholinergic profiles. These were the first-generation promethazine, and second-generation loratadine, desloratadine, and fexofenadine. Hyoscine butylbromide was used in an additional experiment to determine how a peripheral antimuscarinic drug influenced neuromotor function.ResultsPromethazine, desloratadine and fexofenadine increased drowsiness. Promethazine increased simple and choice reaction time and reduced tremor. Desloratadine increased choice reaction time and tremor, while loratadine slowed simple and choice reaction time.ConclusionCentral anticholinergic and antihistaminergic properties of antihistamines potentially contribute to movement dysfunction.SignificanceSecond-generation antihistamines have provided the consumer with a safer alternative to the first-generation sedating antihistamine. However, the results of this study suggest that loratadine and desloratadine have the potential to affect movement control, and further research is warranted to understand the clinical relevance of these findings.     

Familial cortical myoclonic tremor and epilepsy: Description of a new South African pedigree with 30 year follow up

AimThe aims of this study were to report the index case of a South African family with cortical myoclonic tremor and epilepsy, to describe the pedigree with the clinical findings and results of additional investigations, and to report the unique follow-up evaluation of affected and unaffected family members after 30 years.MethodsThe index case led to evaluation of the clinical files of patients from 1978/1979 and clinical assessment and investigation of patients from this cohort as well as newly identified family members. Patients were examined clinically; cortical myoclonic tremor severity was scored by using the Fahn-Tolosa- Marin-Tremor Rating Scale and the Myoclonus Rating Scale. Cortical origin of myoclonus was proven. Statistical analyses were done to assess the impact of cortical myoclonic tremor on quality of life.ConclusionClinical data was available for 23 patients. Increase in cortical myoclonic tremor and age showed a statistically significant correlation with worsening of the sub-score for Quality of Life (FTMTRS) and myoclonus rating scale.After 30 years eleven of fourteen patients could be followed up. Progression of cortical myoclonic tremor severity was noted but epilepsy control was adequate with all patients reporting less than two seizures per year. No clinical features of neurodegeneration were found.DiscussionWe describe the initial presentation and 30 year follow-up of a four generation South African family with FCMTE. The unique long term follow up of this pedigree supports previous findings that the condition does not cause additional progressive neurological deterioration and quality of life is mostly influenced by worsening of the cortical myoclonic tremor with age.     

Autosomal dominant cortical tremor,myoclonus and epilepsy

The term ‘cortical tremor’ was first introduced by Ikeda and colleagues to indicate a postural and action‐induced shivering movement of the hands which mimics essential tremor, but presents with the electrophysiological findings of cortical reflex myoclonus. The association between autosomal dominant cortical tremor, myoclonus and epilepsy (ADCME) was first recognized in Japanese families and is now increasingly reported worldwide, although it is described using different acronyms (BAFME, FAME, FEME, FCTE and others). The disease usually takes a benign course, although drug‐resistant focal seizures or slight intellectual disability occur in some cases. Moreover, a worsening of cortical tremor and myoclonus is common in advanced age. Although not yet recognized by the International League Against Epilepsy (ILAE), this is a well‐delineated epilepsy syndrome with remarkable features that clearly distinguishes it from other myoclonus epilepsies. Moreover, genetic studies of these families show heterogeneity and different susceptible chromosomal loci have been identified.     

Diffusion-weighted imaging study of patients with essential tremor.

The pathophysiology of essential tremor (ET) is unknown. PET and fMRI studies have revealed bilateral activation and (1)H-MRS studies metabolic abnormalities in the cerebellum and other functionally related brain structures in ET. Diffusion-weighted imaging (DWI) was used to search for evidence of tissue integrity abnormalities in these areas in ET patients and 10 matched controls by calculating water apparent diffusion coefficients (ADCs). Regions of interest included the left and right cerebellum, red nucleus, thalamus, caudate, putamen, pallidum, and frontal white matter. Histograms of ADCs were generated for all pixels in the infratentorial compartment and manually segmented areas corresponding to brainstem, vermis, and cerebellar hemispheres. ADC values were similar in all brain areas in patients and controls. Our study did not detect changes affecting the investigated brain regions in ET patients. These findings argue against major structural damage in the ET brain, although more subtle neurodegenerative changes cannot be ruled out.     

Non-motor features in essential tremor

Introduction – Essential tremor (ET) is increasingly recognized to have several non‐motor manifestations. The aim of this study was to determine the prevalence of non‐motor manifestations in ET and its impact on the quality of life (QOL). Methods – This was a cross‐sectional case–control questionnaire‐based study. The subjects were 50 patients with ET and 50 matched healthy controls. All subjects were assessed by Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Parkinson Fatigue Scale, Brief Pain Inventory, Hamilton Anxiety Rating Scale, and Hamilton Depression Rating Scale. In addition, QOL in Essential Tremor questionnaire was administered to patients with ET. Results – Patients with ET, when compared with controls, had significantly higher prevalence and higher mean scores of sleep disturbances (46% vs 8%, P < 0.001; 5.9 ± 4.6 vs 2.6 ± 2.3, P < 0.001), fatigue (30% vs 8%, P = 0.009; 5.8 ± 0.8 vs 2.5 ± 0.4, P < 0.001), anxiety (66% vs 18%, P = 0.009; 7.4 ± 9.0 vs 0.7 ± 2.6, P < 0.001), depression (44% vs 8%, P = 0.009; 7.8 ± 7.9 vs 1.7 ± 3.3, P < 0.001) as well as higher mean score of pain severity (1.9 ± 2.3 vs 0.6 ± 1.2, P = 0.001) and interference owing to pain (2.0 ± 2.9 vs 0.5 ± 1.2, P = 0.001). Following hierarchical regression analysis, depression was the only non‐motor feature that affected the QOL. Conclusion – There was a significantly higher prevalence and greater severity of sleep disturbances, fatigue, pain, anxiety, and depression in patients with ET and depression significantly affected the QOL.     

Wilson's disease tremor is associated with magnetic resonance imaging lesions in basal ganglia structures.

Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra.