Jean-Louis Blatt

Oral festination in Parkinson's disease: Biomechanical analysis and correlation with festination and freezing of gait

In Parkinsons disease (PD), festination corresponds to a tendency to speed up when performing repetitive movements. First described in gait (and then in handwriting and speech), festination is one of the most disabling axial symptoms. To establish the phenomenology of oral festination (OF) and the conditions potential links with other axial disorders, we submitted a simple, rhythmic, repetitive, vocal motor task to 40 PD patients and 20 controls. Forty‐five percent of the 40 patients presented OF, which was strongly associated with gait festination but not with the severity of freezing of gait (FOG) or dysarthria. With respect to the two pathophysiological hypotheses that have been put forward, a possible link with tremor (as previously suggested in tapping) was not confirmed in this study and so, in view of the significant increase in variability observed, we conclude that OF shares the same pathophysiology as gait disorders.

Role of hypokinesia and bradykinesia in gait disturbances in Huntington's disease : A biomechanical study

ObjectiveTo evaluate specific patterns of locomotion in Huntingtons disease (HD) and notably the respective roles of hypokinesia (i. e. a decrease in the amplitude of movement) and bradykinesia (i. e. difficulty in executing a movement, slowness) in gait disturbance.MethodsKinematic, spatial (stride length, speed), temporal (cadence, speed, and stride time) and angular gait parameters (joint ankle range) were recorded in 15 early–stage HD patients by means of a video motion analysis system and then compared with 15 controls and 15 Parkinsons disease (PD) patients. Hypokinesia was studied in terms of both spatial (decrease in stride length) and angular gait parameters (decrease in joint ankle range), whereas hyperkinesia was characterized by an increase in joint ankle range. Bradykinesia (defined by a decrease in gait velocity) was also assessed in terms of temporal parameters (cadence, stride time). We studied the influence of clinical symptoms (motor dysfunction, chorea, overall disability and cognitive impairment) and the CAG repeat number on gait abnormalities.Resultswe observed a clear decrease in gait speed, a decrease in cadence and an increase in stride time (i. e. bradykinesia) for HD, with significant intra–individual variability. Cadence remained normal in PD. In HD, there was no evidence for a clear decrease in stride length, although the latter is a characteristic feature of hypokinetic gait (such as that observed in PD). Angle analysis revealed the coexistence of hyperkinesia and hypokinesia in HD, which thus participate in gait abnormalities. Gait speed in HD was correlated to the motor part of the UHDRS.ConclusionGait in HD is mainly characterized by a timing disorder: bradykinesia was present, with severe intra–individual variability in temporal gait parameters.

Influence of pallidal stimulation and levodopa on gait and preparatory postural adjustments in Parkinson's disease

In order to assess the influence of the bilateral internal globus pallidus (GPi) stimulation on gait and postural instability in Parkinsons disease (PD), we compared gait kinematic parameters and preparatory postural adjustments before and 3 months after stimulation in off‐ and on‐drug conditions for seven patients. Gait kinematic parameters and displacements of centre of pressure (CP) and shoulder computed before a lateral raising task of the leg, were recorded using optoelectric Vicon system. Levodopa (L‐dopa) induced a clear benefit for gait velocity (related to an increase of stride length) and also an increase of swing phase duration. GPi stimulation had a limited effect, since the increase of gait velocity was induced by a concomitant increase of stride length and cadence corresponding to a compensatory mechanism. The benefit on swing phase duration was also moderate. Displacements of CP were improved mainly by L‐dopa. GPi stimulation and L‐dopa had the same beneficial effect on the speed at which the CP was transferred back towards the support side, the ankle velocity, the onset time for ankle displacement, and the decrease of shoulder amplitude towards the support side, which reflects a better postural adjustment phase. This study, based on an objective method, revealed that chronic bilateral GPi stimulation may improve gait and preparatory postural adjustments in severe PD patients with a more limited effect than L‐dopa.

Role of attentional resources on gait performance in Huntington's disease.

Patients with Huntingtons disease (HD) suffer from cognitive deficits with impaired executive functions, including limited attentional resources. We sought to use a dual‐task paradigm to evaluate attentional demands and the ability of patients with HD to concentrate on two tasks simultaneously. We analyzed the interference effects of cognitive and motor tasks on walking in HD and the contribution of clinical symptoms to gait disturbances. Patients and controls were asked to perform either a motor task (carrying a tray with four glasses), a cognitive task (counting backwards), or no task at all while walking at their preferred speed. Kinematic spatial parameters, temporal parameters, and angular parameters related to gait were recorded in 15 patients and 15 controls by means of a videomotion analysis system. Gait instability was assessed using the stride‐to‐stride variability of the various gait parameters. For patients with HD, performing a concurrent cognitive task resulted in a lower gait speed (compared with free walking), with decreased cadence and stride length. However, this effect was not observed in controls. Performing a motor task did not change any kinematic gait parameters in either HD or control subjects. We found correlations between gait speed in the dual cognitive/walking task on one hand and the motor UHDRS score, cognitive status and executive function on the other. Patients with HD had greater difficulty walking while performing a concurrent cognitive task; the drain on attentional resources deteriorated walking performance.

Effect of external cueing on gait in Huntington's disease

In Huntingtons disease (HD) patients, gait is characterized by a timing disorder with marked intraindividual variability in temporal gait parameters (caused by the presence of both hyperkinetic and hypokinetic features). We sought to determine the influence of use of a metronome on gait parameters in patients simultaneously performing motor or cognitive tasks that required attentional resources. The objective is to evaluate the influence of rhythmic cues on gait interference during self‐regulated walking and a dual task paradigm in HD. Fifteen HD patients and 15 paired controls were asked to walk and simultaneously perform another motor task (carrying a tray with four full glasses) or a cognitive task (counting backwards). We evaluated the effect of a metronome (set at 100% and 120% of the subjects self‐determined cadence) in three different task conditions (gait alone, gait + motor task, gait + cognitive task). The use of auditory cues during free gait and dual tasks did not improve kinematic parameters in HD patients, in contrast to the situation for control subjects (improvement in gait speed and cadence but not stride length when the metronome was set at 120% in all conditions). HD patients have difficulty in synchronizing their footsteps with a metronome, mainly due to attentional deficits.

Gait abnormalities induced by acquired bilateral pallidal lesions: a motion analysis study.

BackgroundBilateral pallidal lesions induce a range of cognitive and motor disorders, principally a parkinsonian syndrome in which severe disturbances of gait and gait initiation are frequently reported. However, the precise clinical features of these disorders (and the role of the pallidum therein) remain to be established.ObjectivesThe goal of this study was to characterise gait and gait initiation disorders within the context of a parkinsonian syndrome in patients with acquired, bilateral, pallidal lesions (PAL patients), to compare these disorders to those seen in Parkinson’s disease (PD), and to assess the corresponding physiopathological implications.Patients and methodsBy using a video motion analysis system (VICON), we studied gait kinematic parameters in two patients presenting with bilateral, pallidal lesions. Kinematic and kinetic parameters were also determined during gait initiation. The two patients were compared with a group of 17 PD patients and to 20 healthy controls.ResultsIn both PAL and PD patients, kinematic parameters (gait and gait initiation) and kinetic parameters (gait initiation) were similarly impaired, evidenced by akinesia (difficulty in initiating gait characterized by impairment of anticipatory postural adjustments). Hypokinesia and bradykinesia (respectively reduced stride length and reduced speed during gait) were also noted.ConclusionThe gait and gait initiation disorders seen in cases of bilateral pallidal lesions (namely akinesia, hypokinesia and bradykinesia) are similar to those observed in PD. Subject to confirmation in more extensive studies, we hypothesize that bipallidal patients may present higher level gait disorders,with potential mediation by cognitive impairment.

Caractéristiques évolutives des troubles de locomotion dans la maladie de Huntington

INTRODUCTION Locomotion disorders are important in Huntingtons disease (HD). Although the rates of evolution of motor, functional or cognitive aspects of HD have been studied, the evolution of locomotion disorders in early stages of the disease remains unknown. OBJECTIVES To determine the rate of evolution of the HD-associated gait and gait initiation disorders and their correlates. PATIENTS AND METHODS Eighteen HD patients were recorded with a minimum interevaluation interval of one year. Akinesia was studied by evaluating the anticipatory postural adjustment (APA) phase preceding the first step. We also evaluated gait speed, stride time and stride length. RESULTS We observed an alteration in the APA phase, whose evolution was correlated with that of akinesia. We also observed a decrease in gait speed, which was due both to an increase in stride time and a decrease in stride length. Stride-to-stride variability did not worsen between both evaluations. CONCLUSIONS A worsening in both gait initiation and gait performance was observed in HD. Initial weak functional capacity and more severe motor impairment seem to be associated with a faster progression of locomotion parameters in these mildly impaired HD patients.

Effet de la stimulation cérébrale profonde (pallidum interne, noyau subthalamique) sur la marche dans la maladie de Parkinson

Résumés des présentations orales au Congrès de la Société de Neurophysiologie de Langue Française Toulouse, 24–25 juin 2002 Effet de la stimulation cérébrale profonde (pallidum interne, noyau subthalamique) sur la marche dans la maladie de Parkinson L. Defebvrea,d, P. Krystkowiaka,d, J.L. Blattb,d, J.L. Bourriezb,d, S. Blondc,d, A. Destéea,d, J.D. Guieub,d aServices de neurologie et pathologie du mouvement, Hôpital Salengro, CHRU Lille, France ; bServices de neurophysiologie clinique, Hôpital Salengro, CHRU Lille, France ; cServices de neurochirurgie, Hôpital Salengro, CHRU Lille, France ; dService équipe d’accueil 2683, Hôpital Salengro, CHRU Lille, France Les effets bénéfiques de la stimulation électrique chronique du pallidum interne (GPI) et du noyau subthalamique (NST) sur les signes cardinaux de la maladie de Parkinson sont le plus souvent évalués sur des données cliniques, notamment pour l’analyse des troubles de la marche qui sont constants à un stade évolué de la maladie. Le but de cette étude fut d’analyser objectivement l’effet de la stimulation chronique bilatérale de ces 2 cibles, à partir d’un système optoélectronique d’analyse du mouvement, dans 2 groupes de patients parkinsoniens (7 pour le GPI, 10 pour le NST, durée d’évolution et niveau de handicap moteur comparables). Les paramètres cinématiques suivants ont été calculés avant et 3 mois après l’intervention sans puis après l’administration aiguë de L-dopa : vitesse, cadence, longueur et durée du pas et du cycle de marche, durée des phases de simple de double appuis. Dans le groupe NST, la L-dopa et la stimulation ont entraîné une augmentation franche de la vitesse (respectivement 100 % et 90 %) et de la longueur du cycle de marche (respectivement 68 % et 54 %). Dans le groupe GPI, le bénéfice était moins prononcé (respectivement 32 % et 26 % pour l’effet de la L-dopa et de la stimulation sur la vitesse et 37 % et 18 % sur la longueur du cycle). La réduction de la phase de double appui au profit d’une augmentation de la phase oscillante apparaissait également plus marquée dans le groupe NST. En conclusion, le meilleur bénéfice observé sur les paramètres cinématiques de la marche après stimulation du NST—qui apparaît presque comparable à celui de la L-dopa—serait lié à une restauration optimale des troubles fonctionnels au sein du système des ganglions de la base, à la fois sur les voies ascendantes thalamo-corticales et descendantes vers le tronc cérébral. PII: S 0 9 8 7 7 0 5 3 ( 0 2 ) 0 0 3 1 3 1 Décharges EEG localisées continues pendant le sommeil chez l’enfant : À propos de 10 observations M.D. Lamblin a, S. Suknoc, L. Valléeb, P. Deramburea aService de neurophysiologie clinique, CHRU de Lille, France bService de neuropédiatrie, CHRU de Lille, France Unité de neuropédiatrie Hopital St Antoine, Lille, France Le syndrome de pointes-ondes localisées continues ou de décharges localisées dans le sommeil lent existe-t-il ? À partir de 10 observations d’activation unilatérales de pointesondes dans le sommeil lent de nuit, nous avons tenté, dans le cadre d’une étude rétrospective de vérifier l’existence de cette entité électroclinique et de reconnaître des différences syndromiques entre les formes symptomatiques et idiopathiques afin d’établir une éventuelle orientation pronostique. L’âge de début des décharges localisées se situe entre 3 ans et 11 ans, leur durée entre 3 mois et 10 mois. Rarement cette activation a duré plus de 12 mois L’association ou la précession par des crises étaient inconstantes. Les troubles cognitifs étaient très fréquents mais non constants. enfin, l’amélioration ou la disparition des anomalies EEG et des troubles cognitifs ou des crises étaient obtenues rapidement grâce à un traitement superposable à celui proposé dans un tableau de POCS. L’amélioration ou la guérison n’étaient pas liées à l’existence ou non d’une lésion et à son type. Nous rappelons ainsi l’intérêt de la réalisation d’un tracé de sieste puis de nuit devant tout trouble cognitif récent ou s’aggravant chez un enfant indépendamment de la présence de crises ou de leur fréquence et de la prise en compte au niveau thérapeutique d’une activation localisée de pointes dans le sommeil. PII: S 0 9 8 7 7 0 5 3 ( 0 2 ) 0 0 3 1 4 3 Effets des agonistes dopaminergiques sur la somnolence chez le sujet sain M. Reya, J. Micallefb, C. Audebertb, O. Blin b Centre du sommeil, service de neurophysiologie clinique, Hospital la Timone, Marseille, France ; CPCET, Marseille, France La somnolence diurne excessive est fréquemment observée lors de la prise d’agonistes dopaminergiques chez les patients parkinsoNeurophysiologie clinique 32 (2002) 275–283 www.elsevier.com/locate/neucli