Jeremy P.R. Dick

Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS): Scale Presentation and Clinimetric Testing Results

We present a clinimetric assessment of the Movement Disorder Society (MDS)‐sponsored revision of the Unified Parkinsons Disease Rating Scale (MDS‐UPDRS). The MDS‐UDPRS Task Force revised and expanded the UPDRS using recommendations from a published critique. The MDS‐UPDRS has four parts, namely, I: Non‐motor Experiences of Daily Living; II: Motor Experiences of Daily Living; III: Motor Examination; IV: Motor Complications. Twenty questions are completed by the patient/caregiver. Item‐specific instructions and an appendix of complementary additional scales are provided. Movement disorder specialists and study coordinators administered the UPDRS (55 items) and MDS‐UPDRS (65 items) to 877 English speaking (78% non‐Latino Caucasian) patients with Parkinsons disease from 39 sites. We compared the two scales using correlative techniques and factor analysis. The MDS‐UPDRS showed high internal consistency (Cronbachs alpha = 0.79–0.93 across parts) and correlated with the original UPDRS (ρ = 0.96). MDS‐UPDRS across‐part correlations ranged from 0.22 to 0.66. Reliable factor structures for each part were obtained (comparative fit index > 0.90 for each part), which support the use of sum scores for each part in preference to a total score of all parts. The combined clinimetric results of this study support the validity of the MDS‐UPDRS for rating PD.

Simple and complex movements off and on treatment in patients with Parkinson's disease.

The performance of a 15 degrees elbow flexion and a 30N hand squeeze was studied in nine normal subjects and in five patients with Parkinsons disease. The patients were studied when immobile after 12-18 hours withdrawal from antiparkinsonian drug therapy (OFF) and when more mobile after drugs (ON). Subjects performed each movement separately (simple movements) and both movements either simultaneously or sequentially (complex movements). The duration of both movements and the time between the onset of each movement in the sequential task (interonset latency) were measured. The patients OFF therapy had longer movement times than normal for both movements; these improved after levodopa but still were not normal. When the patients performed complex movements there was an extra slowness, over and above that seen for simple movements, in both movements of the simultaneous task and in the second movement of the sequential task. In addition, the interonset latency in the sequential task was longer than normal. After levodopa there was a more striking improvement in the movement times of complex movements than there had been for simple movements. The interonset latency in the sequential task was shorter than before therapy though still was not the same as in normal subjects. It is suggested that the basal ganglia are not only involved in the execution of simple motor programmes, but also play some role in the superimposition and sequencing of motor programmes.

Patients with Parkinson's disease can employ a predictive motor strategy.

We have tested the hypothesis that predictive motor behaviour is abnormal in Parkinsons disease. In the first experiment elbow movements were performed to track a moving spot on an oscilloscope screen. The performance of 12 patients with Parkinsons disease and eight age-matched control subjects was measured when tracking a repeated pattern under two conditions. In the first condition subjects were not aware of the repetitive nature of the tracking task whilst in the second condition they were. For both groups tracking error and tracking lag were less when aware of the repetition. In the second experiment wrist movements were studied. Five age-matched controls were compared with five patients, studied on and off drugs. In this experiment the performance tracking a repeated pattern was compared to that tracking unpredictable patterns. Tracking lags were reduced to very low values (less than 20 ms) in response to the repeated pattern for both groups. This was true even when the patients were relatively immobile off drugs. We conclude that patients with Parkinsons disease are capable of predictive motor behaviour although such a strategy does not always confer as great an advantage in reducing tracking error in patients compared with control subjects.

Some experiences of techniques for stimulation of the human cerebral motor cortex through the scalp.

Stimulation of the motor cortex transcranially has shown a rough somatotopy of stimulation sites on the scalp corresponding to the homunculus and preferential activation of contralateral hand muscles, as well as very short latencies of signals in the cervical spinal cord. The responses are also facilitated by background activation of the muscles. We are reporting a set of patients studied using electrical and magnetic stimulation transcranially. We observed that the latency of electromyogram activation is much shorter in active than contracting muscles and that the muscle twitch produced by cortical stimulation can exceed the force produced by supramaximal stimulation of the peripheral nerve. Our findings suggest that this may be due to multiple firing of motor neurons. Another observation is that magnetic stimulation is not as subject to a reduction in the response latency with facilitation, and response latencies with magnetic stimulation were 2 ms longer than with electrical stimulation. The implications of these findings are discussed.

Characterization of Corticobulbar Pharyngeal Neurophysiology in Dysphagic Patients With Parkinson's Disease

BACKGROUND & AIMS Dysphagia in patients with Parkinsons disease, persisting despite dopaminergic treatment, affects intake of nutrients and medication, and reduces quality of life (QOL). We investigated the neurophysiologic mechanisms that contribute to dysphagia in these patients, on and off L-3,4-dihydroxyphenylalanine (levodopa), using transcranial magnetic stimulation. METHODS We studied 26 patients with Parkinsons disease (age, 65 ± 9 y; 10 men). Dysphagia and QOL were first assessed with qualitative questionnaires. Twelve hours after patients were taken off levodopa, they underwent cortical transcranial magnetic stimulation mapping of the pharyngeal musculature and trigeminal (bulbar) transcranial magnetic stimulation, as well as videofluoroscopy to examine swallowing. The analyses were repeated after administration of levodopa. RESULTS Eleven patients initially reported dysphagia and reduced QOL scores. Videofluoroscopy identified 10 patients with swallowing impairments on and off levodopa, and 6 patients with swallowing impairments only on levodopa; the remaining 10 subjects showed no swallowing impairments, on or off the drug. While patients were on levodopa, those with swallowing impairments had bilateral increases in pharyngeal cortical excitability compared with those with no swallowing impairment (P < .05). By contrast, with medication, amplitudes of brainstem reflexes were altered only in patients with swallowing impairments on levodopa; these were decreased compared with when the patients were off levodopa. CONCLUSIONS In patients with Parkinsons disease, dopaminergic medications such as levodopa can negatively affect swallowing. The increased cortical excitability observed in dysphagic patients after they begin taking levodopa likely results from compensatory mechanisms, perhaps secondary to subcortical disease, because we observed associated inhibition of brainstem reflexes in patients with affected swallowing on medication. UK clinical trials registration no., 9882.

The effect of gym training on multiple outcomes in Parkinson's disease: A pilot randomised waiting-list controlled trial

There is accumulating evidence for the benefits of exercise in Parkinsons disease (PD), but less is known about group exercise interventions. We evaluated the effect of gym-training programme on people with PD. Thirty-two adults with mild to moderate PD, not currently exercising formally, were randomised to an immediate 20-week biweekly gym training programme at a local leisure complex, or a 10-week programme starting 10 weeks later. Assessments at baseline (T1), 10 weeks (T2) and 20 weeks (T3) included reaction time, motor performance (UPDRS), quality of life and illness perceptions. Experiences of the programme were assessed via questionnaire and a focus group. Overall UPDRS motor function score did not change over time. However, gym training was associated with significant improvements in reaction times and some timed tests in the immediate training group (T1-T2). The delayed group showed similar improvements following gym training (T2-T3). Participants reported enjoyment, obtaining social benefits, and increased confidence. However, the questionnaire measures did not show improvements in subjective health ratings or illness perceptions. Although benefits were not apparent in the questionnaire measures or overall UPDRS scores, our findings suggest that a 10-week gym training programme in a community setting can provide some benefits for people with PD.

Dystonia Associated with Idiopathic Slow Orthostatic Tremor

Background We aimed to characterize the clinical and electrophysiological features of patients with slow orthostatic tremor. Case Report The clinical and neurophysiological data of patients referred for lower limb tremor on standing were reviewed. Patients with symptomatic or primary orthostatic tremor were excluded. Eight patients were identified with idiopathic slow 4–8 Hz orthostatic tremor, which was associated with tremor and dystonia in cervical and upper limb musculature. Coherence analysis in two patients showed findings different to those seen in primary orthostatic tremor. Discussion Slow orthostatic tremor may be associated with dystonia and dystonic tremor.

“Reverse Hoover's sign” demonstrated by neurophysiology in a patient with functional dystonia

A 36 year-old man presented with sudden onset of abnormal painful posturing of the left lower limb, worsening over seven years and exacerbated by walking. There were no obvious underlying psychological stressors. Aside from psoriasis, there was no other medical history. He described sudden exacerbations and remissions of the movements, which could last several months. Botulinum toxin injections to tibialis anterior and extensor hallucis were of limited and short-lived benefit. Examination revealed a fixed deformity of the left foot, which was held rigid at the ankle. This abnormality was fully reversible during examination under spinal anaesthesia. His symptoms further evolved over the following year, with ongoing painful movements of the left and right lower limbs, involving prolonged hip flexion movements, and fixed flexion of the left upper limb, with more subtle posturing of the right upper limb (video clip 1). The movements persisted on walking, with features of a “magnetic gait” and toe-walking (video clip 2). He was referred for neurophysiological studies to further examine his movement disorder and to exclude neurophysiological features of stiff person syndrome. Anti-GAD antibodies were negative. Supplementary video related to this article can be found at

Human Growth Hormone-Related Iatrogenic Creutzfeldt-Jakob Disease—Being Aware of Diagnostic Features 25 Years Later

Department of Endocrinology (K.D., I.K.-A., A.B., S.S., G.B.), The Christie, Manchester M20 4BX, United Kingdom; Department of Neurosurgery (I.K.-A.), Rheinisch-Westfalische Technische Hochschule Aachen University Hospital, 52074 Aachen, Germany; Greater Manchester Neuroscience Centre (J.P.R.D.), Hope Hospital, Salford M6 8HD, United Kingdom; and Department of Radiology (P.M.), The Christie, Manchester M20 4BX, United Kingdom