The purpose of this thesis is to develop and understand dance balance characteristics on various kinds of dance, related positions and shoe types which contribute to dance performance and to understand different balance controls in various groups. The first study was conducted to examine balance into ballet 2nd position between Ballet shoes and Pointe shoes. Eight dancers performed five different conditions in ballet 2nd position (Ballet Flat, Ballet Demi, Pointe Flat, Pointe Demi, and Pointe Toe) and Centre of Pressure (COP) was used to assess balance. The second study was testing balance control and response to perturbations whilst standing on double leg stance dance positions using a moving platform. Four dance positions were performed by eight subjects (Normal Flat, Turnout Flat, Normal Demi and Turnout Demi) and the platform was moved in two different directions (Forward and Backward) at two different speeds (slow and fast). Kinetics, Kinematics and EMG data was taken from this study. The third study was taken to compare balance control and response to perturbations in single leg standing dance positions between eight dancers and eight gymnasts. The subjects performed static single leg balance in Normal Flat, Turnout Flat, Normal Demi and Turnout Demi. Also, perturbed stance trials were collected in anterior, posterior, right and left directions for two dance positions (Normal Flat and Turnout Flat) at two different speeds (slow and fast) on the moving platform. The results from the studies indicate that dancers move in Medial - Lateral direction more than in Anterior - Posterior direction on Demi-pointe and Toe standing by performing plantar flexion during ballet 2nd position. Demi-pointe position may cause longer delay of EMG latencies because CNS is probably sending information already to keep correcting balance on Demi-pointe. Dancers and Gymnasts have different balance controls due to their ways of training in their performance. Dancers generally reacted faster with slow perturbation in Turnout stance than Gymnasts because this is the particular condition which Dancers are training in.

Orientador: Lilian Teresa Bucken Gobbi / Banca: Florindo Stella / Banca: Renato de Moraes / Resumo: Andar é essencial para o desempenho das funções diárias. No entanto, as alterações morfofuncionais decorrentes do processo de envelhecimento podem comprometer o equilíbrio durante o andar e gerar instabilidade. Este comprometimento é ainda mais acentuado em idosos com doença de Parkinson devido aos distúrbios motores ocasionados pela doença. Neste contexto, os objetivos do presente estudo foram: 1) analisar as características espaço-temporais e os ângulos articulares de indivíduos idosos neurologicamente sadios e com doença de Parkinson idiopática andando livremente e em condições de restrição na largura e na altura da superfície de suporte; 2) relacionar estes parâmetros com as pontuações nas escalas de H&Y e UPDRS (apenas para os pacientes) e com a incidência de queda recente (1 ano) e pontuações na Escala de Equilíbrio Funcional de Berg (para ambos os grupos). Participaram 16 idosos distribuídos em dois grupos: oito idosos neurologicamente sadios e oito com doença de Parkinson idiopática. As características espaço-temporais e os ângulos articulares andando livremente e em condições de restrição na largura e na altura da superfície de suporte foram investigados por meio de ferramenta cinemática. Pacientes com doença de Parkinson apresentaram valores médios significativamente menores que os idosos neurologicamente sadios em relação à duração da fase de balanço e ao comprimento e velocidade da passada e maiores para a duração do duplo suporte devido à hipocinesia, à dificuldade no controle do equilíbrio e ao próprio relacionamento entre as variáveis. As restrições impostas pela superfície de suporte geraram alterações nas características espaço-temporais e angulares do andar dos idosos de ambos os grupos, devido à necessidade de adotar uma estratégia cautelosa que facilite o controle da locomoção, garantindo estabilidade, e ao medo de cair imposto pelas demandas da tarefa, ... / Abstract: Walking is crucial for the performance of daily living activities. However, morpho and functional changes due to the aging process can compromise the balance during walking and generate instability. It is more pronounced in elderly patients with Parkinson's disease due to the motor signs/symptoms of the disease. In this context, the aims of this study were: 1) to analyze the spatial and temporal parameters and joint angles of healthy elderly and with Parkinson's disease during free walking and under width and height constraints of the support surface; 2) to correlate these parameters with the scores in H&Y scale and UPDRS (only for patients) and with the occurrence of recent fall (1 year) and the scores in the Berg Functional Balance Scale (for both groups). Sixteen elderly were distributed in two groups: 8 healthy elderly and 8 idiopathic Parkinson's disease patients. Both the spatial and temporal parameters of gait and joint angles were investigated by means of kinematics tools during free walking and under width and height constraints of the support surface. Parkinson's disease patients showed significantly lower mean values than healthy elderly for swing phase duration, stride length and stride velocity, and higher double support duration due to the hipokinesia, the difficulty in balance control, and the relationship among the gait variables. The support surface constraints changed the gait spatial and temporal parameters and joint angles in both groups due to the necessity to perform a cautious walking strategy that can facilitate the locomotor control, preventing instability, and the fear of falling enforced by the task demands, specially when width and height constraints were associated. The scores in H&Y and UPDRS were not correlated to the gait parameters of the Parkinson's disease patients probably because the scales did not reflect the gait performance of patients under medication. There were a relationship among the gait . / Mestre

Estudos prévios têm indicado que o aumento da demanda de estabilidade manual induz maior estabilidade do equilíbrio corporal no controle das posturas quieta e perturbada. O presente estudo teve por objetivo avaliar o efeito da demanda de estabilidade imposta por uma tarefa manual sobre a regulação postural dinâmica em função da frequência de oscilação da base de suporte. Participaram desse estudo 20 estudantes universitários de ambos os sexos. A tarefa consistiu em manter um cilindro o mais estável possível sobre uma bandeja enquanto o equilíbrio em postura ereta era mantido em translações sinusoidais contínuas da plataforma móvel por 1 min., nas frequências de 0,4 Hz (baixa) ou 1 Hz (alta). A demanda de estabilidade manual foi manipulada por meio da disposição do cilindro. Na condição chamada de alta restrição (AR), o cilindro foi apoiado sobre sua face circular; na condição chamada de baixa restrição (BR), o cilindro foi apoiado sobre sua face plana. Os resultados mostraram que AR induziu menores amplitudes de oscilações de cabeça, centro de massa e bandeja na frequência de 0,4 Hz, porém não na frequência de 1 Hz. A análise das variáveis de coordenação revelou que na frequência de 0,4 Hz, AR levou a maiores valores de fase relativa entre as rotações cíclicas de tornozelo-quadril e tornozelo-ombro, como também na coordenação entre CM-plataforma e CP-plataforma. As análises mostraram que a condição de alta restrição também afetou o controle postural e manual na frequência de oscilação de 1 Hz, com aumento da amplitude de oscilação de CP e de rotações do ombro. Estes resultados sugerem que o controle postural dinâmico é regulado em diferentes parâmetros de maneira integrada e flexível, com interação recíproca entre os componentes da tarefa manual e postural, para atender à demanda de estabilidade imposta por uma tarefa posturomanual / Previous studies have indicated that increased steadiness constraints given by a manual task leads to gains of postural stability in quiet and perturbed standing. The aim of the present study was to evaluate the effects of manual task constraints on the regulation of dynamic postural control according to the frequency of sinusoidal translations of the base of support. Twenty university students performed a dual posturomanual task consisting of maintaining a cylinder on a handheld tray as stable as possible while maintaining the dynamic upright balance on a platform oscillating in sinusoidal translations at 0.4 Hz (low) or 1 Hz (high) frequencies during intervals of 1 min. The effects of manual task were studied through the manipulation of task constraint conditions set by positioning the cylinder supported on its round or flat side, corresponding respectively to high (HC) and low (LC) manual task constraints. Results showed that HC led to reduced oscillation amplitudes of the head, center of mass, and tray at 0.4 Hz, but not at 1 Hz. The coordination variables indicated that at 0.4 Hz, HC led to increased relative phase values between ankle-shoulder and hip-shoulder rotations, as also between center of mass-feet and center of pressure-feet oscillations in the slow oscillation frequency. Further analyses showed that the high manual task constraint also affected variables related to both postural and manual task components at 1 Hz, with increased center of pressure and shoulder rotation amplitudes of oscillation. These results suggest that dynamic postural control is regulated through different parameters in a flexible and integrated way in order to attend the stability demands imposed by a posturomanual task

PURPOSE: The aims of this study were to: 1) determine the concurrent validity of the mini-Balance Evaluations Systems Test (BESTest) and the instrumented test of postural sway (iSWAY) to quantify sensory orientation impairments in adults with known postural control deficits; and 2) determine the predictive validity of iSWAY to differentiate between fallers and non-fallers in adults with known postural control deficits. The Sensory Organization Test (SOT) served as the gold standard measure. METHODS: An exploratory methodological design using secondary analysis was used. The sample consisted of 45 subjects with Parkinson¡¦s disease (PD). Subjects were concurrently tested on SOT, mini-BEST, and iSWAY. DATA ANALYSIS: Frequency distributions, central tendencies, variability, and outliers were used to analyze goodness-of-fit to the normal distribution. Mean was used for age while mode was used for fall group, fall status, and gender. The following statistical tests were used: 1) Spearman rank correlation (rs) to measure the relationship between the the mini-BEST and SOT outcome scores; 2) parametric Pearson product-moment correlation (r) was used to measure the relationship between the iSWAY and SOT outcome scores; and 3) multiple regression to analyze the association between several independent variables (iSWAY scores) and dependent variable (number falls). A receiving operator curve was constructed to determine the iSWAY score that best discriminates fallers from non-fallers. RESULTS: There was a significant and fair correlation between mini-BESTest and SOT: Composite and Total rs = 0.380 (p = 0.010); Composite and Sensory rs = 0.343 (p = 0.021), Individual Items Eyes Open, Foam Surface (EOF) and Condition five rs = 0.399 (p = 0.007). There was insignificant and little-to-no relationship between mini-BESTest and SOT Condition one. There was a moderate-to-good inverse correlation between iSWAY and SOT: Composite r = - 0.634 (p = f¬0.01); Individual items ECF and Condition five r = -0.543 (p = f¬0.01). There was significant and fair inverse correlation between iSWAY and SOT Condition one r = -0.432 (p = 0.028). There was a predictive relationship between iSWAY RANGE Composite (p = 0.040) and RMS Composite (p = 0.021) and history of falls. A multiple regression equation including three iSWAY Composite scores explained 38% variability in reported falls. The ROC curve identified an iSWAY RMS Score of less than 0.249 as demonstrating the highest likelihood of differentiating between fallers and non-fallers. DISCUSSION: Mini-BESTest and iSWAY are clinically meaningful measures of sensory orientation in persons with PD. iSWAY can help better quantify sensory orientation impairments and inform other examination findings about history of falls. Future research is needed to investigate validity of these tests with other populations and expand validation of other test components.

No description available.

Submitted in partial compliance with the requirements for the Master of Technology: Chiropractic, Durban University of Technology, 2014. / Background: Poor balance is a risk factor for injury in adolescent sport including soccer. Despite the rapid growth in female adolescent soccer especially in South Africa, the association between balance and injury in this population has not been fully explored. This study aimed to determine the relationship between injury and balance. Static and dynamic balance was monitored as sway index (SI) and limits of stability direction control (LOSDC). Objectives: The objectives of this study were to determine the body mass index of adolescent female soccer players; to determine the prevalence of injury in adolescent female soccer players; to determine static balance as revealed by the sway index (SI); to determine dynamic stability as revealed by limits of stability direction control (LOSDC) and to correlate body mass index (BMI) to sway index and limits of stability. Method: Eighty adolescent female soccer players, between the ages of fourteen and eighteen, were recruited through convenience sampling from schools in the eThekwini district of KwaZulu-Natal. After obtaining informed consent and assent, participants completed questionnaires and were scheduled for the balance and BMI assessments. The objective data for each participant consisted of height, weight, Sway Index (SI) and Limits of Stability Direction Control (LOSDC) readings, measured using a stadiometer, electronic scale and Biodex Biosway Balance System (Biodex Medical Systems Inc., Shirley, New York) respectively. The subjective and objective data were analyzed using SPSS version 21.0 (SPSS Inc. Chicago, Ill, USA). Statistical tests included descriptive statistics using frequency and cross-tabulation. Inferential statistics using t-tests and Pearson’s correlations at a significance level of 0.05 was also incorporated. The testing of hypotheses was performed using Fisher’s Exact tests for nominal data and ordinal data. A p value of < 0.05 was considered as statistically significant. The statistical analysis also included Odds Ratio calculations. Results: The mean body mass index of the injured participants was 23.54±3.56 kg/m2 and the mean body mass index of the uninjured participants was 23.00±4.63. Only 27.5% of the participants sustained an injury. Injured participants performed poorly on average in the SI assessment involving their eyes open when standing on a soft surface. The results were similar for the LOSDC in the overall, right, left, backward-right and backward-left directions. However, there were no significant correlations calculated. Significant relationships existed between BMI and the SI assessments in the injured participants which involved standing on a firm surface with their eyes open (p = 0.05), their eyes closed when also standing on a firm surface (p = 0.05), their eyes open when standing on a soft surface (p = 0.02), and their eyes closed when standing on a soft surface (p = 0.04). A significant relationship also existed between BMI and LOS right direction control (p = 0.02). Conclusion: This research paper revealed that the body mass index as investigated in this study is similar to other studies involving female adolescents; soccer injury as investigated in this study is similar to other studies involving female adolescents; poor static and dynamic balance is not associated with injury in adolescent female soccer players and lastly, body mass index is linked to the balance of an individual.

The central integration of sensory information provided by various afferent receptors is required to control human movement. Although the function of individual afferent receptors is known, the complexity and interactivity of afferent information remains unclear, especially in scenarios which involve the reduction of information provided by one or more afferent receptors. Reduced plantar sensitivity is commonly associated with postural instability, which occurs in ageing, peripheral neuropathies, and other neurological disorders like Parkinson's disease. Although there has been a great advance in understanding afferent inputs during recent years, the role of afferent information in controlling movement is still unclear. Therefore, the aim of the present thesis is to investigate the effects of reduced plantar sensitivity on quasi-static and dynamic balance control, as well as muscle reflexes. The current thesis is comprised of five experiments. Two experiments were designed as preliminary investigations, while the remaining three experiments addressed the main questions of this thesis. The first experiment investigated a basic question about subjective foot sensitivity (vibration perception) measured in two different body positions: standing and sitting. Results of Experiment I showed no differences of vibration perception between both measured conditions. Therefore, comparing data from plantar sensitivity vibration tests performed during sitting and during standing (e.g. balance) is feasible. In Experiment II, the role of afferent information from plantar mechanoreceptors on quasi-static balance was investigated using two different cooling procedures: a permanently cooling thermal platform and conventional ice pads. COP total excursions, plantar temperatures, and scores of a Visual Analogue Scale (VAS) regarding subjective pain were analyzed. Experiment II demonstrated that constant and controllable cooling via the thermal platform is the superior approach with respect to subjective pain (VAS) and to reach and maintain the desired temperature throughout the trials. Furthermore, only cooling via the thermal platform induced postural instability, revealed by increased COP values. This instability was expected due to reduced plantar input, indicating no compensation by other sensory systems. Experiment III focused on the inter- and intraday- reliability of dynamic balance responses using the Posturomed device. Generally good relative and absolute reliability were found for COP excursions. This outcome was fundamental to proceed with dynamic balance measurements using the same setup. Subsequently, effects of reduced plantar cutaneous inputs via cooling on anticipatory and compensatory balance responses (unexpected perturbations) were explored in Experiment IV. COP and EMG data were used to analyze anticipatory and compensatory balance responses. No differences in COP or EMG parameters were found for the anticipatory responses after hyper-thermia, while decreased values for compensatory balance responses were observed in response to cooling. This was interpreted as a kind of overcompensatory behavior of the central nervous system (CNS) due to more cautious behavior induced after plantar cooling. Finally, the question regarding the interaction between afferent receptors arose in Experiment V, in which the effects of reduced plantar temperatures on the Achilles tendon stretch reflex and plantar flexion were examined. Short latency responses and maximal force of plantar flexion were analyzed. Cooling resulted in decreased amplitudes of short latencies, as well as in delays in time to maximal force of plantar flexion. These findings suggest that plantar inputs participate complementarily in the Achilles stretch reflex. Collectively, the current thesis contributes to understanding how plantar receptors are involved in movement control; not only do they seem to work as independent contributors, but they also appear to interact with other afferent receptors. Furthermore, an important outcome is that the reduced plantar inputs seem to induce different alterations in the organization of CNS inputs and outputs, according to different balance tasks: quasi-static responses, anticipatory responses, and compensatory responses. For the future, the use of other methods like microneurography and electroencephalography could be helpful to gain even more understanding of afferent interactions during the control of movements. Similar protocols may also be implemented in other populations, such as elderly people or patients suffering from neurological disorders, who exhibit continued decline or degeneration of sensory receptors. / Die zentrale Integration von sensorischen Informationen, die aus verschiedenen afferenten Rezeptoren zur Verfügung gestellt werden, ist erforderlich, um die menschliche Bewegung zu steuern. Obwohl die Funktion der einzelnen afferenten Rezeptoren bekannt ist, bleibt die Komplexität und Interaktivität von afferenten Information unklar, insbesondere in Szenarien, in denen die Verminderung von Informationen aus einem oder mehreren afferenten Rezeptoren eintritt. Reduzierte plantare Sensibilität wird häufig im Zusammenhang mit Haltungsinstabilität verbunden. Dies tritt häufig während des Alterns ein, bei peripheren Neuropathien und anderen neurologischen Erkrankungen, wie etwa bei der Parkinson-Krankheit. Obwohl es in den vergangen Jahren große Entwicklungen was das Verständnis afferenter Inputs gab, ist die Rolle afferenter Information bei der Bewegungskontrolle immer noch unklar. Daher ist das Ziel der vorliegenden Dissertation, den Einfluss der Beeinträchtigung der plantaren Sensibilität auf das quasi-statische und dynamische Gleichgewicht, sowie auf den Reflex der Achillessehne, zu untersuchen. Die vorliegende Dissertation ist dazu aus fünf Untersuchungen aufgebaut. Zwei Untersuchungen werden als Voruntersuchungen präsentiert, während die übrigen drei Untersuchungen auf die Kernfragen dieser Doktorarbeit gerichtet sind. Die erste Untersuchung beschäftigt sich mit der grundlegenden Fragestellung bzgl. der subjektiven Fußsensibilität (Vibrationswahrnehmung), die in zwei verschiedenen Körperpositionen gemessen wurde: Im Stehen und im Sitzen. Ergebnisse aus Untersuchung I zeigten keine Unterschiede der Vibrationswahrnehmung zwischen den beiden Körperpositionen. Daher ist es möglich, Vergleiche zwischen Daten aus plantaren Vibrationswahrnehmungstests während des Sitzens und des Stehens (z.B. bei Gleichgewichtstests) durchzuführen. In Untersuchung II wurde die Rolle afferenter Informationen plantarer Mechanorezeptoren auf das quasi-statische Gleichgewicht mittels zwei unterschiedlicher Abkühlverfahren untersucht: eine permanente Abkühlung durch eine thermische Plattform und konventionelle Eis-Pads. Es wurden der COP Gesamtweg, plantar Temperaturen und eine visuelle Analogskala (VAS) in Bezug auf subjektive Schmerzen analysiert. Untersuchung II hat gezeigt, dass eine konstante und steuerbare Abkühlung über die thermische Plattform der überlegene Ansatz in Bezug auf subjektiven Schmerz (VAS) und bzgl. des Erreichens und Erhaltens einer gewünschten Temperatur innerhalb der Messungen ist. Weiterhin wurde nur durch die Abkühlung mittels thermischer Plattform eine posturale Instabilität induziert, evident durch erhöhte COP Gesamtwege. Diese Instabilität wurde aufgrund der Beeinträchtigung der plantaren Sensibilität erwartet, was auf eine fehlende Kompensation durch andere Sinnessysteme hinzuweisen scheint. In Untersuchung III lag der Fokus auf der inter- und intra-Tag-Reliabilität dynamischer Gleichgewichtsantworten mittels des Posturomed-Trainingsgerätes. Im Allgemeinen wurden eine gute relative und absolute Reliabilität der COP Gesamtwege ermittelt. Dieses Ergebnis war von grundlegender Bedeutung, um die Nutzung des gleichen Setups für die folgenden dynamischen Gleichgewichtsmessungen (Untersuchung IV) zu ermöglichen. Anschließend wurden die Effekte einer Beeinträchtigung der plantaren Sensibilität mittels Abkühlung auf antizipatorische und kompensatorische Antworten des dynamischen Gleichgewichts (anhand unerwarteter Störungen des Gleichgewichts) in Untersuchung IV erforscht. COP und EMG Daten wurden verwendet, um die antizipatorischen und kompensatorischen Antworten des Gleichgewichts zu analysieren. Nach der Abkühlung wurden bzgl. antizipatorischer Antworten keine Unterschiede in den COP und EMG Parametern gefunden. Im Hinblick auf kompensatorische Antworten zeigten sich reduzierte COP und EMG als Reaktion auf die Abkühlung. Dies wurde wie folgt interpretiert: aufgrund eines vorsichtigen Verhaltens, ausgelöst durch die verminderten sensorischen Inputs infolge der Abkühlung, kam es zu einer Art „Überkompensierungsverhalten“ des zentralen Nervensystems (ZNS). Schließlich stellte sich die Frage der Interaktion afferenter Rezeptoren in Untersuchung V, in welcher die Effekte reduzierter plantarer Temperaturen auf den Achillessehnen-Dehnungsreflex und die Plantarflexion untersucht wurden. Kurze Latenz Antworten (short latency responses) und die maximale Kraft der Plantarflexion wurden dabei analysiert. Die Abkühlung führte zu einer verminderten Amplitude der short latency responses sowie zu Verzögerungen der Zeit bis zur maximalen Kraft der Plantarflexion. Diese Ergebnisse deuten darauf hin, dass plantare Inputs in komplementärer Weise am Achillessehnen-Dehnungsreflex beteiligt sind. Zusammenfassend lässt sich aussagen, dass die vorliegende Arbeit zum Verständnis beiträgt, wie plantare Rezeptoren an der Bewegungssteuerung beteiligt sind. Es scheint, dass diese nicht nur in unabhängiger Form zur Bewegungssteuerung beitragen, sondern dabei auch mit anderen afferenten Rezeptoren interagieren. Darüber hinaus ist ein wichtiges Resultat, dass die reduzierten plantaren Inputs scheinbar verschiedene Änderungen in der Organisation von Ein- und Ausgängen im ZNS induzieren. Dies erfolgt anhand unterschiedlicher Anforderungen an das Gleichgewicht: quasi-statische Antworten, antizipatorische Antworten und kompensatorischen Antworten. Für die Zukunft könnte die Implementierung anderer Methoden, wie Mikroneurographie und Elektroenzephalographie, hilfreich sein, um noch mehr Verständnis bezüglich afferenter Interaktionen während der Kontrolle von Bewegungen erlangen zu können. Ähnliche Protokolle könnten auch in anderen Populationen durchgeführt werden, wie ältere Menschen oder Patienten mit neurologischen Erkrankungen, die einen kontinuierlichen Rückgang oder Degenerationen sensorischer Rezeptoren zeigen.

The Posturomed device is used as a scientific tool to quantify human dynamic balance ability due to unexpected perturbations, and as a training device. Consequently, the question arises whether such measurements are compromised by learning effects. Therefore, this study aimed to analyze inter- and intra-day reliability of dynamic balance responses using the Posturomed. Thirty healthy young subjects participated (24.3±3.2 years). The Posturomed was equipped with a triggering mechanism to enable unexpected, horizontal platform perturbations. A force platform was used to quantify Center of Pressure (COP) excursions for two time intervals: interval 1 (0–70 ms post perturbation) and interval 2 (71–260 ms post perturbation). Dynamic balance tests were performed in single leg stances in medio-lateral and anterior-posterior perturbation directions. Inter- and intra-day reliability were assessed descriptively using Bland-Altman plots and inferentially using tests for systematic error and intra-class-correlations. With regard to the mean COP excursions for every subject and all intervals, some cases revealed significant differences between measurement sessions, however, none were considered relevant. Furthermore, intra class correlation coefficients reflected high magnitudes, which leads to the assumption of good relative reliability. However, analyzing inter- and intra-day reliability using Bland-Altman plots revealed one exception: intra-day comparisons for the anterior-posterior direction in interval 2, which points towards possible learning effects. In summary, results reflected good overall reliability with the exception of certain intra-day comparisons in the anterior-posterior perturbation direction, which could indicate learning effects in those particular conditions.

Background Anticipatory and compensatory balance responses are used by the central nervous system (CNS) to preserve balance, hence they significantly contribute to the understanding of physiological mechanisms of postural control. It is well established that various sensory systems contribute to the regulation of balance. However, it is still unclear which role each individual sensory system (e.g. plantar mechanoreceptors) plays in balance regulation. This becomes also evident in various patient populations, for instance in diabetics with reduced plantar sensitivity. To investigate these sensory mechanisms, approaches like hypothermia to deliberately reduce plantar afferent input have been applied. But there are some limitations regarding hypothermic procedures in previous studies: Not only plantar aspects of the feet might be affected and maintaining the hypothermic effect during data collection. Therefore, the aim of the present study was to induce a permanent and controlled plantar hypothermia and to examine its effects on anticipatory and compensatory balance responses. We hypothesized deteriorations in anticipatory and compensatory balance responses as increased center of pressure excursions (COP) and electromyographic activity (EMG) in response to the hypothermic plantar procedure. 52 healthy and young subjects (23.6 ± 3.0 years) performed balance tests (unexpected perturbations). Subjects’ foot soles were exposed to three temperatures while standing upright: 25, 12 and 0 °C. COP and EMG were analyzed during two intervals of anticipatory and one interval of compensatory balance responses (intervals 0, 1 and 2, respectively). Results Similar plantar temperatures confirmed the successful implementation of the thermal platform. No significant COP and EMG differences were found for the anticipatory responses (intervals 0 and 1) under the hyperthermia procedure. Parameters in interval 2 showed generally decreased values in response to cooling. Conclusion No changes in anticipatory responses were found possibly due to sensory compensation processes of other intact afferents. Decreased compensatory responses may be interpreted as the additional balance threat, creating a more cautious behavior causing the CNS to generate a kind of over-compensatory behavior. Contrary to the expectations, there were different anticipatory and compensatory responses after reduced plantar inputs, thereby, revealing alterations in the organization of CNS inputs and outputs according to different task difficulties.

Tyrimo objektas: pacientų, persirgusių galvos smegenų insultu pusiausvyra. Problema: Lietuvoje klinikinėje praktikoje nėra plačiai taikomi pusiausvyrą vertinantys testai ar skalės. Darbo tikslas: įvertinti pusiausvyros testų informatyvumą pacientams, persirgusiems galvos smegenų insultu. Uždaviniai: įvertinti pacientų pusiausvyros sutrikimus Bergo, Brunelio pusiausvyros bei liemens kontrolės įvertinimo skalėmis praėjus 2, 4, 6 savaitėm po insulto bei palyginti šių skalių rodiklius. Tyrimo metodika: naudojant Bergo ir Brunelio pusiausvyros bei liemens kontrolės įvertinimo skales buvo vertinama pacientų, persirgusių išeminiu smegenų insultu, pusiausvyros sutrikimai ir jos pokyčiai reabilitacijos eigoje. Tyrimo duomenys statistiškai buvo apdoroti naudojantis kompiuterine programa SPSS 13,0 for Windows. Rezultatai: testuojant ligonius liemens kontrolės įvertinimo skale po 2 savaičių nagrinėjamos funkcijos vidutiniškai sudarė 48,2%, po 4 savaičių 76,8%, o po 6 – 91,8% maksimalios balų sumos (p<0,05). Bergo skalės rezultatai po 2 savaičių tesudarė 17,8%, po 4 savaičių nagrinėjamo rodiklio vidutinė reikšmė ženkliai padidėjo ir tapo lygi 37,3%, o po 6 savaičių registruota reikšmė buvo didesnė (p<0,05) nei po 4 savaičių ir sudarė 59,2%. Brunelio skalės vertinimo rezultatų kaita po 2 savaičių buvo 26,3%, po 4 savaičių tiriamųjų pateiktų užduočių vertinimas siekė 54,2%, o tyrimo pabaigoje – 72,5% (p<0,05). Išvados: 1. Liemens kontrolės įvertinimo skalės didžiausias pusiausvyros... [toliau žr. visą tekstą] / Object of the study: balance of patients after stroke. Problem of the study: there are no widely used balance tests and scales in the clinical practice in Lithuania. Aim of the study: to evaluate informative of balance scales for patients after stroke. Objectives: to evaluate balance disability of patients after stroke during 2, 4, 6 weeks with Brunel, Berg balance and postural assessment scales and compare their indexes. Methods: balance disability was measured with the use of the trunk control and balance items of the Postural Assessment, Berg’s and Brunel’s balance scales for patients after stroke. Research data was analyzed using SPSS 13,0 for Windows. Results: the results of postural assessment scale for stroke patients after 2 weeks post stroke average makes 48,2%, after 4 weeks it was 76,8%, and the last – 91,8% of maximal total points (p<0,05). Evaluation of Berg balance scale after 2 weeks reach 17,8%, after 4 weeks indexes value improve a lot and makes 37,3%, after 6 weeks this value was bigger and makes 59,2% (p<0,05). The results fluctuation of Brunel balance scale after 2 weeks were 26,3%, after 4 weeks improve twice – 54,2% and 72,5% in the end of evaluation. Conclusions: 1. The biggest improvement of balance of postural assessment scale for stroke patients observed after 2 stroke weeks, between 2-6 weeks – gradually slow down, but approach maximal indexes in the end of the search. 2. Berg balance scale indexes during three evaluations improve gradually, though... [to full text]