INVITED SPEAKERS ABSTRACTS

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1 Rev. Bras. Fisiot. Suplemento Especial 7 INVITED SPEAKERS ABSTRACTS VISUAL DEFICITS AND THEIR EFFECTS ON MOBILITY: IMPLICA TIONS FOR GAIT REHABILITA TION Patla, Aftab E., University of Waterloo, Ontario, Canada Vision provides unique sensory information for the control of locomotion. Control of dynamic stability, adapting the basic patterns of gait for different environments and guidance of locomotion towards endpoints not visible from the start are adversely affected when vision is compromised. In this presentation, the focus will be on effects of various deficits on the control of gait on step by step basis rather than the effects on route planning. Visual deficits in the peripheral sensory apparatus examined include age-related cataracts, age-related maculopathy, and loss of one eye. The accuracy and precision of gait patterns over uneven terrain is differentially influenced by these pathologies. Loss of foveal vision affects the accuracy of limb elevation when stepping over low contrast low obstacles, while presence of cataracts affects both accuracy and precision of limb elevation control over small obstacles. Loss of one eye forces individuais to provide a larger safety margin over high obstacles, modify the stepping patterns and use head roll movements to acquire depth information. Damage to the ventral stream emanating from the primary visual cortex spares the visuomotor transformations for precise control of lower limb movements. While deficits such as cataracts can be corrected by surgery, appropriate adaptive strategies have to be developed to deal with most visual deficits. Knowing the terrain and ambient conditions that pose greatest threat to mobility is the first step; creating and implementing rehabilitation training in these environments is necessary. In addition, patients need to be trained to develop the compensatory strategies to acquire appropriate sensory information to guide locomotion. Supported by grants from Health Canada and NSERC Canada. ASPECTOS DA BIOMECANICA PARA ANALISE DO MOVIMENTO HUMANO: CONSIDERACOES SOBRE FORCAS INTERNAS. Amadio, Alberto Carlos, Laboratorio de Biomecanica, Escola de Educacao Física e Esporte da Uni v. de Sao Paulo, Brasil. Discute-se a conceituacao da biomecanica, no contexto de uma disciplina que, entre as ciencias derivadas das ciencias naturais, ocupa-se com analises físicas de sistemas biologicos, conseqentemente, analises físicas de movimentos do corpo humano. Assim, atraves da biomecanica e de suas areas de conhecimento correlatas podemos analisar as causas e fenomenos relacionados ao movimento humano. A biomecanica interpretada como uma ciencia multidisciplinar, levando-se em consideracao cada domínio do conhecimento ou sub-disciplina que compoe esse espectro, que investiga o movimento. Considera-se portanto o movimento humano como o objeto central de estudos onde analisamos suas causas e efeitos produzidos em relacao a biomecanica. Pela obvia dificuldade metodolgica de acessarmos o comportamento biomecanico de estruturas internas dos sistemas biologicos, a sua parametrizacao em termos de variaveis biomecanicas internas se torna extremamente dependente de medicoes externas ao organismo, ou seja, observadas exteriormente, ou por equacoes de estimacao, na composicao de modelos para a determinacao destes parmetros internos ao aparelho locomotor. Entre os estudos biomecanicos que buscam descrever indicadores do comportamento das variaveis dinamicas durante a marcha, por exemplo, tem-se usado a forca reacao do solo como componente descritivo primaria para indicar a sobrecarga no aparelho locomotor durante a fase de apoio, pois ela reflete a somatoria dos produtos da aceleracao da massa de todos os segmentos do corpo. Com relacao a corrida, devemos considerar duas tecnicas de movimento que podem influenciar a distribuicao de cargas ao aparelho locomotor: (a) corredores de retro-pe (constituem-se em aproximadamente 80%) e (b) corredores de ante-pe (20%), em acordo com BAUMANN (1992). Ao observarmos a curva forca de reacao do solo em funcao do tempo, os corredores de retro-pe e os de ante-pe apresentam comportamentos diferentes, os primeiros com e os segundos sem a presenca de um pico de forca inicial. O impulso e aproximadamente o mesmo pois, ambos apresentam o mesmo peso corporal e deslocam-se a mesma velocidade. Entretanto as forcas articular e muscular na articulacao do tornozelo indicam enormes diferencas entre ambas as situacoes de sobrecarga em funcao portanto das tecnicas de movimento. O corredor de ante-pe apresenta uma carga no tendo de Aquiles, aproximadamente 25-30% maior se comparado ao corredor de retro-pe. A mesma relacao observada para a forca articular, considerando-se para a articulacao do tornozelo. Observamos assim valores para a forca de compressao articular ao redor de 9 vezes o peso corporal. Desta maneira consideramos ser a Biomecanica um importante ramo de interacao com areas diversas que se aplicam ao estudo do movimento humano. Logo em funcao destes parametros estabelecemos a validade para a analise do movimento, na busca de sua otimizacao, nao apenas no sentido de eficiencia mas ainda em relacao a um processo de economia e controle motor da tecnica de movimento. _,

2 8 Rev. Bras. Fisiot. Suplemento Especial ANTICIPATORY POSTURAL ADJUSTMENTS IN HEALTH AND DISEASE Aruin, Alexander S. Rehabilitation Foundation, Inc. Wheaton Illinois, USA Voluntary limb movements are virtually always associated with changes in the activity o f postura! muscles. Some of these changes occur prior to the movement and can be addressed as anticipatory. Their assumed role is to minimize perturbation of the limb or body posture that would otherwise be induced by the movement. Another group of reactions in postura! muscles occurs!ater. This group may be considered compensatory reactions to the perturbations induced by the intended movement. Anticipatory postura! adjustments (APA) have been investigated since the pioneering study of Belenkii et ai. (1965) who showed that changes in the electromyographic activity of postura! muscles in standing humans appears prior to a voluntary movement of an upper limb and are specific to this movement. The process of generation of anticipatory postura! adjustments is likely to be affected by three major factors: 1) Expected magnitude and direction of the perturbation; 2) Voluntary action associated with the perturbation; and 3) Postura! task (e.g. a body configuration). Effects of these three factors have been studied relatively extensively, however, a contribution of each of them to anticipatory postura! adjustments is not quite clear because they are interrelated (for review see Massion, 1992). Experiments with load manipulations let the experimenters separate the effects of the magnitude of motor action and of the magnitude of perturbation upon the AP As. Such studies have suggested that both the magnitude of the action and the magnitude of the perturbation can affect APAs independently. In particular, our experiments with voluntary actions of different apparent magnitude (small finger flexion movements vs. bilateral shoulder abduction movements) demonstrated a scaling of APAs with the magnitude of the voluntary action used to induce the perturbation, while the magnitude of the perturbation was always the same. The results of the other study demonstrated the anticipatory postura! adjustment scale with the expected magnitude of a perturbation when the voluntary action was always the same (Aruin, Latash, 1995, 1996a). We know much less currently about the effect of postura! task on anticipatory postura! adjustments. Reports on the dependence of AP As on the stability demands o f the postura! task have been somewhat conflicting, suggesting that the dependence may be non-monotonic. In particular, APAs associated with voluntary movements were attenuated or absent when the posture was unstable as well as when it was very stable. Our recent experiments have demonstrated that the magnitude o f AP As in conditions o f a standard perturbation triggered by a standard motor action by the subject, depends on two factors related to the postura! task, namely, the plane ofpostural instability and the effective width of support. The results of our own studies of anticipatory postura! adjustments in conditions of postura! instability combined with that provided by others have allowed us to formulate a hypothesis that anticipatory postura! adjustments themselves may be perturbations to balance, and that the lack of anticipatory postura! adjustments in conditions of postura! instability represents a defensive strategy of the central nervous system (CNS). Adaptive changes in APAs that have been seen in patients with postura! instability, and in healthy subjects while posture is unstable (generation o f anticipatory postura! adjustments in healthy persons in conditions of postura! instability may also be challenging, so that postura! instability may be used as a model of postura! impairment), support our conclusion. The task of generating anticipatory postura! adjustments may be trivial for the CNS of a healthy person, but it may be challenging for a person with a neurological disorder (such as Parkinson's disease), an inborn deficiency (e.g., Down syndrome), a lower Iimb amputation leading to a major disruption of the biomechanical and neurophysiological relations developed during the lifetime, or for a person whose ability to perform voluntary movements is impaired by natural reasons (e.g., aging). Motor disorders in Down syndrome (DS) are commonly addressed as "clumsiness." Two major components of clumsiness in DS include slowness of the movements and the inability to rapidly respond to the changing environment (for reviews se e Corcos, 1991; Latas h and Anson, 1995 ). In a number of postura[ and movement tasks, persons with DS frequently use atypical coactivation patterns of muscle activity seen in both, anticipatory and compensatory reactions (Aruin and Almeida, 1997). There is substantial variability among the studies of anticipatory postura! adjustments in Parkinson's disease (PD). The reports vary from minor changes in the anticipatory reactions in Parkinson's disease (Diener et ai.; 1989, Latash et ai. 1995, Aruin et ai., 1996b) to the lack of anticipatory postura! adjustments in 95% of patients with Parkinson's disease (Bazalgette et a!., 1986). The slowness of voluntary movements in Parkinson's disease (bradykinesia) apparently leads to smaller reactive torques during voluntary movements and, as a consequence, to smaller postura! perturbations. Hence, possible sources of variability among the studies of anticipatory reactions in PD may be the different motor tasks used, different amounts of practice, and other factors leading to different efficacy of voluntary movements as postura! perturbations. Patients after a below knee amputation demonstrated a general pattern of larger anticipatory changes in the activity of muscles on the intact side of the body as compared to symmetrical muscles on the side of amputation which may reflect central adaptive changes secondary to the amputation (Aruin et ai., 1997). Studies directed to understanding the nature of anticipatory postura! adjustments in healthy adults combined with investigation of assisted recovery of postura! contra! in neurological patients may suggest ways of improvement of rehabilitation strategies whose purpose is to assure adequate postura! contra! in cases o f postura! disorders. ACKNOWLEDGEMENTS This work was supported in part by grant HD from the National Center for Medica! Rehabilitation Research, NIH.

3 Rev. Bras. Fisiot. Suplemento Especial ASSESSMENT OF GAIT REHABILITA TION THROUGH EVALUA TION OF JOINT EFFORTS Quevedo, Antonio A. F. Dept. o f Biomedical Engineering, Fac. o f Electrical and Compu ter Engineering, State University o f Campinas, Brazil INTRODUCTION Gait rehabilitation can be achieved through several different techniques, according to the cause of motor defcit. Biomechanical evaluation techniques are an important tool for movement studies in pathologic subjects. These techniques, if adequately adapted, could provide important information regarding the assessment of conventional and non-conventional gait rehabilitation techniques. This work refers to parameters related to joint efforts, which are a major concern when dealing with gait restoration. METHODS Angular accelerations are directly related to joint rotational moments. If one wants to avoid excessive effort on joints, it is important to keep accelerations within acceptable Jimits. However, Jimitation of acceleration peaks is not enough to prevent joint damage. Even if values are kept within the normal peak Iimits, the average acceleration can be higher than normal. The acceleration module integral (AMI) can be used as a safety parameter. If AMis for all joints can be kept within the values found for normal subjects, the restored gait can be considered "safe". Direct use of rotational moments of force could theoretically provide more realistic estimates. Thus, moment module integrais (MMI) can be used in the same way as for accelerations. As moments are usually normalized according to body mass, the same procedure was used in the current work. For parameter estimation on normal subjects, data from (Winter, 1991) was used. For comparison, data from a clinicai case (Vaughan et al, 1992) was used. Clinicai case is a Cerebral Palsy subject with subtalar ankle artrodesis. Gait cycle was normalized by interpolation to 100 samples (0-99% in increments of 1 %). Sample signal was then canceled (modulus function) and the 100 samples were summed. RESULTS Tables 1 and 2 present the values obtained for the normal sample and for the clinicai case. l~ linical linical DISCUSSION AND CONCLUSION (R); (L) (R); (L) (R); (L) Table 1: AMI values (rad/s2) Table 2: MMI values (N.m/kg) AMis are greatly increased in the clinicai case. As joint efforts were expected to increase due to lack of movement optimization, the proposed parameter seems to reflect well these efforts. Thus, AMis can be used as quantitative parameters for assessing rehabilitation techniques. MMis, though, presented unexpected results. According to Table 2, values are above normal standard for hip and knee joints, as expected, but below normal for ankle joints. According to (Winter, 1991), computation of rotational moments are subjected to cummulative errors, which come from estimation of body segment inertias and from other sources as well. Due to the contradictory results found for MMis, and considering that computational cost and errors for calculation of rotational moments are much higher than the ones for accelerations, preference must be given to AMI values. Estimation of body segment inertias would also be subjected to more errors when gait rehabilitation techniques include the use of orthoses. REFERENCES D. A. Winter. The biomechanics and motor control of human gait: Normal, elderly and pathological, University of Waterloo Press, C. L. Vaughan et al. Dynamics of human gait, Human Kinetics Publishers, ACKNOWLEDGMENTS The author would like to thank CNPq, CAPES, FAPESP, and FAEP (Brazil) for the granting support, as well as Dr. David Winter and Dr. Christopher Vaughan for kindly allowing the use of their data in this work. FACTORS CONTRIBUTING TO MOTOR REHABILITATION IN INFANTS WITH DOWN SYNDROME AND SPINA BIFIDA Ulrich, Beverly D., Ph.D., Department of Kinesiology, Indiana University, Bloomington, IN 47405, USA. Designing effective intervention programs for people with movement problems must involve consideration of several factors. Two of the most important factors are (a) what does the person have to work with (e.g., leveis of muscle strength, motivation, motor control) and (b.) what is the process that underlies changes in motor performance. Because individuais are complex beings, they come to the rehabilitation setting with many different intrinsic capacities, even though they may be classified as having Down syndrome, cerebral palsy, or spina bifida. How one chooses to help each infant or child acquire motor skills must be based on a theory of what drives change in behavior. This, I propose, is the same underlying process for all of us regardless of levei of ability. 9

4 10 Rev. Bras. Fisiot. Suplemento Especial In my talk I will discuss, briefly, some of the principies that drive change in motor performance, namely, principies from dynamic systems theories. I will spend most of my time elaborating those principies by sharing results from severa! research studies out of our Motor Development Laboratory. Our laboratory team has been studying infants with Down syndrome and infants with spina bifida. I believe our results have implications for designing intervention programs that will help people learn to acquire functional motor skills. THE ROLES OF MOTION AND PHYSICAL AGENTS IN CONNECTIVE TISSUE REHABILITATION Enwemeka, Chukuka S., P.T., Ph.D., FACSM, Department ofphysical Therapy, University ofkansas Medicai Center, 3901 Rainbow Boulevard, Kansas City, KS USA Unlike most soft tissues that require 7-10 days to heal, primary healing of tendons takes at least six weeks during which they are protected in immobilization casts. Such long periods of immobilization impair motor rehabilitation and predispose a multitude of complications including, muscle atrophy, trophic neural changes, osteoarthritis, skin necrosis, infection, tendo-cutaneous adhesion, re-rupture, and thrombophlebitis. If healing can be quickened, then, the duration of cast immobilization can be reduced to minimize the deleterious effects of immobilization. In separate studies, we tested the hypothesis that early weight-bearing, ultrasound, He-Ne laser, and Ga-As laser, when used singly or in combination, accelerate the healing process of experimentally tenotomized and repaired rabbit Achilles tendons as evidenced by biochemical, biomechanical, and morphological índices of healing. Our results warrant the conclusions that: (1) appropriate doses of each modality, i.e., early weight-bearing, ultrasound, He-Ne and Ga-As laser therapy augment collagen synthesis, modulate maturation of newly synthesized collagen, and overall, enhance the biomechanical characteristics of the repaired tendons. (2) Compared to the physical agents, i.e., ultrasound, and laser therapy, early weight-bearing offers the most potent stimulus for accelerating the healing process of repaired tendons. (3) Combinations of either of the two lasers with early weight-bearing and either ultrasound or electrical stimulation further promote collagen synthesis when compared to early weight-bearing alone. However, the biomechanical effects measured in tendons receiving the multi-modality therapy were similar, i.e., not better than the earlier single modality trials. Although healing of repaired human tendons may differ from healing of the rabbit Achilles tendon, these findings suggest that human cases of Achilles tendon repair may benefit from appropriate doses of early weight-bearing, ultrasound, He-Ne laser, and Ga-As laser therapy when used singly or in combination with one another. Furthermore, our findings warrant the suggestion that early weight-bearing alone may offer sufficient stimulus to optimize healing o f repaired tendons. Funded by The NIH-NCMRR, The NIDRR, and V A-RR&D. SUMMARY KNOWLEDGE OF RESULTS (KR) AND DELAYED PRESENTATION SCHEDULES OF KR WITH ELECTROMYOGRAPHIC BIOFEEDBACK: A REPORT OF TWO EXPERIMENTS. Gable, Clayton D., Ph.D., PT, Texas Tech University Health Sciences Center, Texas, USA. BACKGROUND AND PURPOSE Electromyographic biofeedback is used clinically to provide augmented feedback to person about their level of neuromuscular activity. Clinically, it is used to assist in neuromuscular reeducation and to assist in relaxation training. In both cases, the common practice of biofeedback has been based upon principies of behavior modification with the assumption that the feedback concerning an individual task needs to be closely associated (temporally) with the task. Consequently, many commercially available biofeedback systems utilize these ideas of close association in the design their circuitry and/or computer programs. In recent years the motor learning literature concerning feedback has used paradigms of delaying the presentation of feedback in a number of different manners (e.g., summary KR, relative frequency, trials delay, etc.). The conclusions of these studies have stated that provision of feedback in too close proximity has a negative effect on retention performance of the task in question. The two experiments reported here utilize common paradigms in motor Jearning research. Experiment #1 investigated the effect of two relative frequencies of presentation of knowledge of results (KR: feedback) and the effect of summary KR presentation compared with immediate KR. Experiment #2 investigated the relative effect of four different task-kr time intervals. EXPERIMENT #1: Experiment #1 compared the effects of four different conditions of KR presentation on retention performance on a motor performance task. Summary KR (presentation of KR for ali trials after a pre-determined number of trials have been completed) and decreased relative frequency of KR (presentation of KR on every other trial or every fifth trial, etc) demonstrate positive effects on retention performance of a task as compared to immediate KR (presentation of KR related to a trial after every trial). This particular phenomenon has been explained in terms of the guidance hypothesis which states that immediate KR presentation fosters a dependency upon the KR for accurate performance rather than promoting the deeper cognitive processing necessary for learning. By its very design EMG biofeedback is immediate KR. EMG biofeedback is typically provided either during the task or immediately following a cumulative measure for a specified duration oftime (i.e., integrated EMG over a millisecond period). The task was to learn to produce a contraction of 20% of maximum voluntary contraction (MVC). The experimental groups consisted of the following: KRS 5 (summary KR after every 5 trials); KRS 10 (summary KR after every 10 trials); KR 50 (KR after every other trial); KR 100 (KR after every trial). Subjects were 39 male and female volunteers (age range of 55-85). Subjects was asked to perform an isometric contraction of the right triceps with the elbow at 90 degrees flexion. Following the MVC, subjects were randomly assigned to one of four testing groups. Measurements were made with an AC amplifier and collected to a microcomputer. Ali measurements consisted of collection of raw surface EMG to the computer and then integration of the 5 second time period of the task. Each subject performed 15 blocks of 10 trials on the task and received feedback in accordance with their assigned

5 Rev. Bras. Fisiot. Suplemento Especial condition. Feedback was provided visually (bar graph) via a custom written computer program and in terms of percent levei of contraction deviation from the target value of 20% MVC. After a 10-Minute retention delay each subject engaged in a nofeedback test of their retention peformance of the task. Each subject then returned the next day for another retention test at approximately 24 hours!ater. RESUL TS: Analysis of Absolute Constant Error (ACE) for the acquisition trials was performed in a 2-way ANOVA for repeated measures of KR Condition (4) x Block (15) and failed to reveal a significant main effect for KR Condition. There was a main effect for Block on ACE, F(14,490)=2.80, P< which demonstrated that the subjects improved across the acquisition trials. Analysis of Variable Error demonstrated significance for KR Condition, F(3,35)= 3.50, p<.025 and Block, F(l4,490)=3.04, p< The 10-Minute Retention interval ACE and VE were analyzed in a KR Condition (4) one-way ANOV A and failed significance. The 24-Hour Retention data was analyzed in a one-way ANOV A for KR Condition on ACE, F(3,35)=3.513, p<.0251 and on VE, F(3,35)=2.856, p<.051. Duncan's New Multiple Range Test indicated that the KR 50 condition (M =.1634) and KR 100 ( M=.l046) performed with the greatest ACE compared with KRS 5 (M=.072) and the KRS 10 (M=.0367) (ali units are in percent ofmvc). EXPERIMENT #2: Experimental conditions on #2 represented a manipulation of the time interval between the end of the task and the presentation of KR. The time intervals evaluated were.5, 2, 5, and 10 seconds. Subjects included 48 male and female volunteers (mean age: 31). Procedure and apparatus were the same as in Experiment #1 with the exception of 10 blocks of 15 trials each. RESULTS: Analysis of ACE and VE for the acquisition trials was performed in a 2-way ANOV A for repeated measures of KR Condition (4) x Block (10) and failed significance for KR Condition. A Block main effect was demonstrated for ACE, F(9,396)=5.30, p<.0001 and VE, F(9,396)=4.43, p<.0001 with subjects demonstrating steady improvement across blocks of trials. For the 10-Minute Retention interval one-way ANOV A of ACE revealed a main effect for KR Condition, F(3,47)=4.2883, p< Analysis of VE failed to demonstrate significance. For the 24-Hour Retention interval the same trend of bias toward poor retention performance for the.5 second group was maintained but a one-way ANOV A failed significance. CONCLUSION: These experiments present evidence that many of the findings related to feedback presentation in other motor Jeaming tasks may also apply to the realm o f EMG biofeedback and impact the clinicai practice o f biofeedback. PARKINSON'S DISEASE: MOTOR DEFICITS AND INTERVENTION APPROACHES Corcos, Daniel, University of Illinois of Chicago, USA Parkinsons's disease is a progressive neurological disorder that is clinically characterized by bradykinesia, rigidity and tremor. Patients can also have abnomal postura! reflexes. Over the last twenty years considerable progress has been made in refining our understanding of the motor problems of Parkinson's disease. Deficits have been found in the performance of a variety of movement tasks that range fr0m reduced muscle strength to higher order deficiencies in the ability to generate movement sequences, especially when there are no externai stimuli available to guide the movement sequence. In addition to the progress in our understanding of the various movement deficits in Parkinson's disease, the treatment of Parkinson's disease is progressing rapidly on three different fronts. First, there has been a considerable advance in understanding of the role of the basal ganglia in the control of movement. Second, there are severa! destructive neurosurgical treatments available for the treatment of PD. These include posteroventral pallidotomy and thalamotomy, as well as implanting high frequency stimulators in the pallidum, sub thalamic nucleus and vim nucleus of the thalamus. Third, restorative neurosurgery shows promise. Currently, there are investigative trials to evaluate the efficacy of implanting fetal tissue and administering various neurotrophic factors. The presentation will focus both on current conceptualizations o f the motor deficits o f Parkinson's disease as well as how different neurosurgical interventions improve the motor performance o f patients with Parkinson's disease. RULE-BASED CONTROL FOR FUNCTIONAL ELECTRICAL STIMULA TION ASSISTED WALKING Popovic, Dejan B. Faculty o f Electrical Engineering, University o f Bel grade, Yugoslavia Functional electrical stimulation (FES) can be used for restoration of standing and locomotion of humans with spinal cord injury (SCI) with limited success. The most likely reason for limitations is the lack of an efficient controller. Existing control algorithms typically use an analytical, dynamic model of the human body and methods of robotics. The body is presented as a complex system o f rigid segments connected with rotational joints and powered by a set of joint actuators [e.g., Zajac, 1989]. However, even the most complicated model proposed is far from reality. Actuators implement visco-elastic, Hill-based model with some variations which take into account specific characteristics of human musculo-skeletal system [Winters, 1990]. There is no model for locomotion that takes into account the characteristics of the segmented spinal column, upper body, neck and the head. The instrumental data needed for the design of a control algorithm, when using analytic approach, is a trajectory. The goal is to design a control system for FES-assisted locomotion. The system will be used by humans with SCI; thus, it is essential to: 1) take into account that substantial changes in the neuro-musculo-skeletal characteristics will be caused by the injury; and 2) accept the fact that humans with paralysis will not be able to walk with a pattern alike normal (e.g., using crutches or a walker, missing proprioception and decreased exteroception). These two elements make the dynamic approach for control extremely unsuitable. The alternative method for synthesizing bipedal gait of a human with SCI can be imagined as cloning of an ablebodied subject walking. Walking with a constant speed, over even terrain, with no or small perturbations is a cyclic activity, which can be considered as a finite automaton. The automaton includes sensory inputs (propriception, exteroception, joint 11

6 12 Rev. Bras. Fisiot. Suplemento Especial receptors, etc.) and motor (muscle) outputs as reviewed in Prochazka [1993]. Implantable and externai sensors are now getting available, and FES resolves major problems in getting muscles to work. However, neither sensors are replica, not FES is ideal for completely replicating able-body functioning. The problem; thus, is that cloning of this kind is impossible since the performances of a clone can not match the original. The task for cloning of able-bodied type of locomotion therefore includes two phases: 1) using customized biomechanical model of a potential user of the assistive system and able-body gait data to simulate the gait. Simulation will generate a matching map of muscle activity patterns and sensory data. The number o f muscles should be equal to the number o f FES channels and the number o f sensors to the number o f transducers that would be used in a practical FES system. The simulation deals with the reduced model; thus, the results match the eventual assistive system functioning [Popovic et ai., 1998]; and 2) determining the matching between the inputs and outputs. The matching process is de facto designing of a finite automaton. The matching in this study is exclusively based on machine learning [Jonic et ai., 1998]. Various procedures for designing finite automata are described in literature [Tomovic et a!., 1995]. Those rules can be either: 1) heuristically defined, which is known as "hand-crafted system", or 2) automatically generated using artificial intelligence tools, such as neural networks. In the "hand-crafting" approach the researcher based on his or her previous experience and intuition defines contrai rules. Such a system is then implemented to real FES-assisted locomotion application and the quality of the resulting gait is assessed, necessary adjustments are completed and the process is repeated again until a satisfactory gait is achieved [Kobetic and Marsolais, 1994]. This "trial and error" method is very time consuming and complex. The biggest disadvantage of this method is that the performance of the resulting contrai system depends on the experts' ability to express the acquired knowledge explicitly in form of states and rules. Fast development of artificial and computational intelligence techniques, such as artificial neural networks, adaptive logic networks, fuzzy logic brings new approach to the control system design problem formulation and solution. Following the early work ofmichie and Chambers [1968] on an algorithm known as "boxes" implemented in the "pole balancing" paradigm. Inductive learning technique to contrai of FES-aided walking of subjects with incomplete spinal cord injury was implemented [Heller et ai., 1993]. The control rules were extracted by cloning skills of a subject with SCI when manually controlling a simple two-channel-per-leg FES-system and for the swing-through walking. Veltink et ai. [1992] used a backpropagation multi-layer perceptron network for reconstructing muscle activation patterns in the walking cycle on the basis of signals recorded from externai sensors (goniometers and foot-switches). Kostov et a!., [1994] used adaptive logic networks to clone manual triggered walking of an incomplete tetraplegic walking. The most important question of a generalization from machine learning technique training to a real-time contrai application remained unanswered in most of the works described above. After preliminary results demonstrated possibility of using neural networks for designing contrai rules for FES-assisted walking of subjects with incomplete SCI [Kostov et ai., 1994; Nikolic and Popovic, 1996], a similar approach was adopted as the basis for this study [Jonic et ai., 1998; Jonic and Popovic, 1998]. Machine learning algorithms are compared for their ability to reconstruct muscle activation patterns (output) from preceding sensory data (input). Three algorithms are presented here: 1) symbolic, based on minimization of entropy called inductive learning- IL; 2) connectionist, radial basis functions type of artificial neural network (ANN) with radial-basis functions (RBF); and 3) their combination. A rule-based IL estimation is explicit, easy to implement, computationally simpler, and easy to comprehend, compared to ANN, although there are methods which extract approximate classification rules from trained ANN, and they contribute to giving readability to the ANN. A rule-based estimation does not work well enough for estimation of the muscle activity levei, and ANN does not work well enough for estimation of the muscle timing. ANN gives a continuous output, whereas rule-based leaming gives a discrete output. One solution isto combine rule-based and ANN methods to get the best from both approaches. We found that this combination gives the best results for the mapping. The work on this project was partly supported by the Serbian Ministry of Science and Technology, Belgrade, Yugoslavia; the Miami Project to Cure Paralysis, University of Miami, Miami, Florida, USA; The Medicai Research Council of Canada, Ottawa, Ontario, Canada, and the Alberta Heritage Foundation for Medicai Research, Edmonton, Alberta, Canada. I would like to acknowledge the contributions of Aleksandar Kostov, Ph.D., Zoran Nikolic, Ph.D. and Slavica Jonic, MS while working towards their degrees at the University o f Alberta, University o f Miami and University o f Belgrade A V ALIAÇÃO MUSCULAR RESPIRATÓRIA Costa, Dirceu, Prof Dr., Coordenador de Pesquisa e Capacitação, Depto. de Fisioterapia da Pró-Reitoria de Pós-Graduação e Pesquisa da UFSCAR Os músculos respiratórios do ser humano, apesar de não perderem a característica de músculo estriado esquelético, apresentam aspectos funcionais e mecânicas diferenciados tendo em vista sua atuaçf.o constante e ininterrupta, durante todo o ciclo da vida. Tal fato faz com que ao avaliar esses músculos, seja introduzido elementos de medida que considerem de forma cuidadosa, o produto do trabalho mecânico, dentre tantos outros elementos normalmente mensurados. Dentro deste contexto, torna-se indispensável a combinação e/ou complementação das ferramentas de trabalho, bem como a maior variação possível dos elementos de procedência do indivíduo e do tipo de movimento ou de padrões de respiração.

7 Rev. Bras. Fisiot. Suplemento Especial Técnicas de medidas como a Eletromiografia e as Pressões Respiratórias Máximas (Pimás e PEmáx), têm sido empregadas nesta avaliação, com o objetivo específico de se conhecer a Força e a Endurance envolvidas no trabalho muscular respiratório. As medidas Antropométricas e Espirométricas, por sua vez, tem sido muito útil neste processo de avaliação, tanto nos indivíduos sadios como em pneumopatas e, quando associadas ao teste de esforço, em atletas ou em indivíduos submetidos a treinamento físico regular. A avaliação muscular respiratória, quando realizada com critérios fisiológicos e mecânicos e, considerando-se um conjunto de informações sobre procedência, modalidade de movimento, etc., constitui num importante mecanismo esclarecedor de dados indispensáveis na saúde respiratória do ser humano. DIVERSIFICAÇÃO E COMPLEXIDADE NO COMPORTAMENTO MOTOR ADAPTADO Manoel, Edison de J., USP, São Paulo. O processo de desenvolvimento motor há duas classes de mudanças. Primeiro, há o ganho em diversificação do comportamento em função do aumento no número de elementos. Inicialmente, há o acoplamento entre intenção e a realização de algum objetivo no ambiente. Os meios para alcançar o objetivo não estão claros e o comportamento caracteriza-se por grande inconsistência. Com a definição dos meios mais adequados para a solução há um ganho de consistência seguido por um aumento gradual de variabilidade devida à exploração de meios alternativos para a realização do objetivo. Essa diversificação implicará em melhoria na adaptabilidade do comportamento, bem como poderá levar ao surgimento de novos meios para atingir o mesmo fim (por exemplo, a locomoção que era realizada pelo andar ereto passa a ser efetuada pelo correr). A segunda classe de mudanças refere-se ao ganho em complexidade do comportamento caracterizado pelo aumento nas interações entre os elementos. Os padrões de movimento diversificados, passam a ser integrados em padrões mais complexos. Por exemplo, o correr e o arremessar podem ser gradualmente combinados em uma habilidade mais complexa e específtca até ao nível daquelas habilidades observadas em modalidades esportivas (por exemplo, no basquetebol ou handebol). O ganho em complexidade não implica apenas executar em seqüência dois padrões, ele implica em modificações na organização espacial e temporal de cada padrão de acordo com a meta geral da habilidade complexa. Diversificação e complexidade são classes gerais de descrição das mudanças no desenvolvimento do comportamento motor. Entretanto, é possível gerar hipóteses explicativas a partir delas como será discutido nesta apresentação. Atenção especial será dada à análise do comportamento de pessoas portadoras de deficiência mental. As soluções motoras encontradas por esses indivíduos, bem como o curso do desenvolvimento apresentado, não são deficientes mas diferentes. A caracterização e explicação do comportamento e desenvolvimento motor adaptado podem beneficiar-se da consideração das duas classes de mudanças mencionadas. Para a discussão de questões referentes à diversificação serão apresentados dados referentes ao padrão de arremessar e para as questões referentes à complexidade serão apresentados dados da combinação de padrões de correr e arremessar. Em ambos casos, com pessoas portadoras de deficiência mental ou neurológica. MECANISMOS DE CONTROLE MOTOR EM UMA ATIVIDADE FUNCIONAL: O MOVIMENTO DE SEDESTAÇÃO À BIPEDESTAÇÃO. Goulart, Fátima R. de Paula, Departamento de Fisioterapia, Universidade Federal de Minas Gerais, Brasil e Josep Valls-Solé, Unidad de EMG y Contra! Motor, Hospital Clinico, Barcelona, Espaíia O movimento de sedestação à bipedestação (msd-bp) é uma atividade motora complexa que envolve a ativação de músculos posturais e de músculos que são os principais responsáveis pela execução do movimento. O principal objetivo deste estudo foi caracterizar a fisiologia e, especialmente, os mecanismos de controle usados pelo sistema nervoso central (SNC) para a realização do msd-bp. O estudo que será apresentado foi realizado com 40 sujeitos sadios e foi dividido em três partes. Na primeira parte foi feita uma análise da atividade eletromiográfica (EMG) de músculos envolvidos no msd-bp. A segunda parte foi destinada a caracterizar as mudanças de excitabilidade da via motora descendente e do circuito reflexo segmentário durante a execução do movimento e, na terceira parte, examinou-se a excitabilidade dos motoneuronios lombares a partir de impulsos descendentes e dos aferentes periféricos nas duas posturas extremas: sentado e de pé. A metodologia utilizada foi o registro EMG, a ativação das vias descendentes através da estimulação magnética cortical e a ativação do circuito reflexo segmentário por estimulação elétrica do nervo tibial posterior na fossa poplítea (reflexo H). Os resultados mostraram que: 1. O msd-bp é gerado pela ativação de um programa motor que envolve os músculos paravertebral, quadríceps e isquiotibial. A ativação de tais músculos segue a ativação de músculos envolvidos em ajustes posturais que são específicos para a posição inicial ou estratégia motora utilizada para a realização do movimento. Tibial anterior, soleo, abdominal, esternocleidomastoide e trapézio são exemplos de músculos com função postura!. 2. O sistema efetor modifica sua excitabilidade antes do início do msd-bp. Existe um amplo aumento na excitabilidade da via motora descendente em músculos do tronco e da perna, enquanto que a excitabilidade motoneuronal aos impulsos aferentes periféricos apresentam um padrão de inibição recíproca entre músculos agonista e antagonista. 3. O mecanismo de inibição pré-sináptica dos impulsos aferentes musculares primários está ativo no músculo soleo e tibial anterior na postura de pé. O controle de tal mecanismo pelo SNC é provavelmente um requerimento para a estabilidade postura! em bipedestação. 13

8 14 Rev. Bras. Fisiot. Suplemento Especial AN AUTOMATIC ADAPTIVE NMES CONTROL SYSTEM FOR GAIT SWING RESTORATION IN SUBJECTS WITH SEVERE SPINAL CORD LESION Sepulveda, F, A, Biomedical Engineering Dept. UNICAMP, Brazil, M.H. Granat e A. Cliquet Jr*Bioengineering Unit, University of Strathclyde, Glasgow, UK Introduction: Control systems for gait restoration in spinal cord injured (SCI) subjects must be closed-loop and adaptive. To this end, Sepulveda et al. (1997) recently presented an artificial neural system which was useful but relied on hurnan intervention for activation of the on-line learning scheme. This work presents an automatic on-line learning strategy for the latter system. Methods: A three-layer artificial neural network was used for adaptive control of gait swing generated by neuromuscular electrical stimulation (NMES) in a spinal cord injured subject. Network inputs consisted of knee and ankle goniometer signals. Output values were proportional to changes in the NMES Pulse Width (PW) applied to the femoral and common peroneal nerves, respectively. On-line learning was activated in automatic mode. When the generated step correlated well with normal trajectories, an enhanced supervised backpropagation scheme was applied with desired outputs corresponding to leaving PW values unchanged. However, when the generated angles did not correlate well with normal trajectories, Punishment was applied. Correlation coefficients were calculated by comparing measured angles with angular data from an average normal male. For testing purposes thus far, PW changes produced by the on-line learning scheme were compared to those generated by a neural network trained only off-iine. Results: In a sample test, after a good step was generated with ch1=895 JJS and ch2=894 JJS, the off-line system predicted changes in PW equal to -152 JJS and s for ch1 and ch2, respectively. This led to a poor step being generated after the good one. On the other hand, the latter PW changes were -37 JJS for ch1 and +5 JJS for ch2 in a simulation with the automatic on-line scheme, thus maintaining the PW values near those which had led to a good step. In general, the automatic on-line learning scheme behaved better than the off-line system only when punishment was needed. Conclusions: According to tests, the automatic on-line learning strategy presented here is an improvement over the original, human-activated system. The strategy is prornising and should soon be submitted to clinicai tests for a further evaluation. Bibliography: F. Sepulveda, M.H. Granat, A. Cliquet Jr. (1997). 'Two artificial neural systems for generation of gait swing by means of neuromuscular electrical stimulation'. Medica[ Engineering and Physics, V oi. 19(1) in press. The authors wish to thank Brazil's FAPESP and CNPq, and UNICAMP's FAEP for suporting this research CONSIDERING THE FUNCTIONAL ROLE OF THE STRETCH REFLEX: DEVELOPMENT, NORMAL FUNCTION AND PATHOLOGY Gottlieb, Gerald L., Boston University e Barbara M. Myklebust, The George Washington University The stretch reflex has a played a large, long and controversial role in the study of motor control. While its role in the maintenance of normal posture is relatively well accepted, some also argue for its fundamental participation in the general task of controlling voluntary movements. In this talk, we will review findings of the last 15 years that suggest that the stretch refi ex plays a broad, excitatory role within the spinal cord of the normal neonate. One of the achievements of normal development isto reduce and focus that excitation into appropriate channels. We will show that this reduction and focussing does not occur in children with spastic cerebral palsy and some other motor disorders andas a result, may be one contributor to movement deficit. We will also show that in normal movement, the stretch reflex plays a modest and non-stereotypical role. We will show that segmenta! stretch reflex mechanisms are not the static, stereotyped "negative feedback" system that they are traditionally described as but an evolving, adjustable system. ROBOT-AIDED NEUROREHABILITATION: TWO YEAR FOLLOW-UP Krebs, H.I. 1 ; Aisen, M.L. 2 ; Volpe, B.T. 2 ; Hogan, N. 1 ' 3 1 Massachusetts Institute of Technology, Mechanical Engineering Department, Newman Laboratory 2 Cornell University Medicai College, Department Neurology and Neuroscience, Burke Institute of Medica! Research 3 Massachusetts Institute o f Technology, Brain and Cognitive Sciences Department Our goal is to apply robotics and information technology to assist, enhance, quantify, and document rehabilitation following neurological injury and in particular, stroke. Recent reports showed that stroke patients treated daily with additional robot-aided therapy during acute rehabilitation had improved outcome in motor activity at hospital discharge, when compared to a control group that received only standard acute rehabilitation treatment. Outcome improvement was limited to the muscle groups trained in the robot-aided therapy (Aisen et ai, Arch Neurology, 54: , 1997; Krebs et ai, IEEE-Transactions on Rehabilitation Engineering, 6:1:75-87, 1998). To test if this improved outcome was sustainable, we are recalling the twenty patients enrolled in that study two years (approximately) since they were discharged. The same standard assessment procedure (of the initial study) was administered by the same "blinded" therapist. Table I summarizes preliminary results from 9 patients recalled so far (5 experimentais, 4 controls).

9 Rev. Bras. Fisiot. Suplemento Especial 15 Patient Group Fugl-Meyer Motor Power Motor Status Score, Motor Status Score, (out of 66) shoulder & elbow shoulder & elbow wrist & finger (out of 20) (out of 40) (out of 42) ~1 ~2 ~3 M ~2 ~3 ~1 ~2 ~3 M ~2 ~3 Ex per Control T ABLE I. Motor recovery o f 9 patients approximately 2 years after discharge as measured by severa! standard clinicai instruments. ~1 denotes the change between admission and discharge; ~2 denotes the change between 2 years after discharge and at discharge; ~3 denotes the change between 2 years after discharge and at admission. Patients in the experimental group received robot training; those in the contrai group did not. These preliminary data should be interpreted with care due to the small number of subjects. Nevertheless, it is striking that seven out of nine patients continued to improve substantially in the period following discharge. lf this finding is borne out in further study, it would challenge the common perception that patients stop improving after about 11 weeks poststroke (see, e.g., Jorgensen et ai, Arch Phys Med Rehab, 76:5: and 76:5: The Copenhagen Stroke Study) and suggest that there may be an opportunity to further improve the motor recovery of stroke patients by continuing therapy in the out-patient phase, for example, using the technology that is the focus of our project. Note further that, comparing the overall recovery (between admission and 2 years after discharge) the MSS for shoulder and elbow (which were the focus of robot training) of the experimental group improved twice as much as the control group, whereas the MSS of wrist and fingers (which were not trained) improved by essentially the same amount for both groups. These preliminary results in a two year follow-up corroborate our in-patients studies, indicating that the benefits of robot-training (and training in general) are specific to the muscle groups or limb segments exercised. MUSCLE ACTIVATION PATTERNS IN UPPER LIMB MOTOR TASKS PERFORMED BY INDIVIDUALS WITH DOWN SYNDROME Anson, J. Greg, Rachei Lockie, Trish Gorely, Grant Mawston, School of Physical Education,University o f Otago, New Zealand When initiating fast, discrete arm movements, individuais with Down syndrome (DS) present a distal-to-proximal pattern of muscle activation. For example, in a task that required participants to hit a target as fast as possible with the index finger, extensor indicis activation preceded that of anterior deltoid. Chronologically age-matched, non DS individuais demonstrated a predicted proximal-to-distal activation pattern. The reasons for a difference in DS activation patterns are not clear but they do not appear to include: dependence on visual feedback; nerve conduction velocity; or specificity of task instruction. We have now quantified severa! characteristics associate with the electromyograms (EMG) of selected muscles in individuais with DS, and likewise, in chronologically age-matched contrai subjects. For contrai subjects, EMG profiles indicate a triphasic response in ali three agonist-antagonist pairs of muscles (anterior deltoid!posterior deltoid; biceps/triceps; extensor indicislflexor digitorum superficialis). Reaction time (RT) occurs within the duration of the first agonist burst. In DS, triphasic responses were infrequent. Most DS EMG profiles revealed cocontraction between agonist-antagonist pairs of muscles. Furthermore, EMG in the agonist muscles of DS participants was often characterized by a series of bursts of EMG that increased in magnitude during the response, diminishing just before target contact occurred. The failure to dissociate agonist and antagonist muscle activation could be one explanation for the altered pattern observed in individuais with DS during performance of discrete, rapid aiming movements. COORDENAÇÃO INTRA-MEMBROS NA PASSADA DO ANDAR EM HEMIPLÉGICOS Barela, J.A., Departamento de Educação Física, IB, UNESP, Rio Claro. A ocorrência de um acidente vascular cerebral (A VC), muitas vezes, provoca danos aos neurônios motores em um dos hemisférios cerebrais e, consequentemente, deficiência no controle da musculatura de um lado do corpo. Esta dificuldade unilateral em controlar movimentos voluntários é denominada de hemiplegia e acarreta inúmeras mudanças na capacidade de locomoção. Por exemplo, após um A VC, as pessoas andam consideravelmente mais devagar, com uma assimetria temporal entre a ação dos membros inferiores e com padrões de ativação muscular muito diferentes dos verificados em pessoas normais. Apesar destas diferenças terem sido extensamente estudadas, muito pouco é conhecido sobre o relacionamento entre os segmentos dos membros inferiores na medida que eles realizam a passada do andar. Qual é o relacionamento do segmento da perna e da coxa em uma passada realizada por um hemiplégico? Este relacionamento é diferente de uma passada realizada por pessoas normais? Neste estudo, respostas a estas questões são buscadas a partir de um referencial baseado na perspectiva dos sistemas dinâmicos. Clark e colegas (p. ex., Clark & Phillips, 1993) sugeriram que a fase relativa constitui uma variável coletiva que representa o padrão de coordenação entre os segmentos perna e a coxa no ciclo da passada em pessoas normais.

10 16 Rev. Bras. Fisiot. Suplemento Especial A identificação de uma variável coletiva permite verificar como a coordenação entre os segmentos muda durante um ciclo da passada ou durante um período de tempo. No caso de pessoas que sofreram AVC, esta abordagem tem o potencial de identificar mudanças no processo de reabilitação decorrentes de intervenção terapêutica. Desta forma, o objetivo deste estudo foi de descrever o comportamento dos segmentos perna e coxa e investigar o relacionamento entre eles, coordenação intramembros, durante o andar em pessoas hemiplégicas. Seis sujeitos hemiplégicos crônicos e seis sujeitos normais foram filmados (60Hz), a partir de uma vista lateral com marcas em pontos articulares específicos, andando com velocidade preferida. Três ciclos do andar para cada lado do corpo dos sujeitos hemiplégicos (afetado e não afetado), e três ciclos para o lado direito do corpo dos sujeitos normais foram digitalizados, utilizando o sistema Peak Performance. Os dados cinemáticos, posição e velocidade angular, foram calculados e os retratos de fase, descrevendo o comportamento de cada segmento, e os ângulos de fase foram obtidos para os segmentos da perna e da coxa. A fase relativa, entre estes dois segmentos, foi calculada subtraindo o ângulo de fase da perna do ângulo de fase da coxa. Os valores da fase relativa, em pontos específicos do ciclo, referentes ao lado afetado, não afetado e normal foram comparados através de MANOV AS. A descrição do comportamento da perna e da coxa, através dos retratos de fase, indicou diferenças entre os lados afetado e não afetado e entre estes dois e o normal. A fase relativa entre a perna e coxa revelou que o relacionamento entre estes segmentos é diferente na maior parte do ciclo da passada entre os lados afetado e não afetado. Apenas no início do ciclo (próximo do toque do pé no solo) os lados afetado e não afetado não diferem um do outro. Comparados com o ciclo normal, os lados afetado e não afetado apresentam diferenças significativas antes e durante a fase de balanço. Estas diferenças são decorrentes principalmente da dificuldade em produzir força contra o solo por parte do lado afetado para iniciar a fase de balanço. Isto afeta apenas este lado, mas faz também que o lado não afetado tenha que compensar sua ação, neste período do ciclo. Isto sugere que a coordenação entre a perna e coxa é alterada em pessoas hemiplégicas devido a inabilidade de aplicar uma força no chão para propiciar o início da fase de balanço na perna afetada. PHSYSIOLOGICAL BASIS OF RISKS VERSUS BENEFITS OF EXERCISE TRAINING IN CARDIOV ASCULAR DISEASES Gallo Jr.., Lourenço, Divisão de Cardiologia, Depto. de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, USP. Physical exercises, a common and spontaneous activity of everyday life, is one of the most complex physiological processes know. Moreover, no other physiological activity can overload the biological systems to a comparable extent. In particular, this applies to cardiorespiratory function when dynamic exercise is performed at high intensity workloads. Muscle contraction for more than a few seconds needs the support of severa) biological systems for the entire organism to cope with the energy demand required by the exercising muscles. In this situation, the efficiency of the cardiorespiratory system is controlled by a highly hierarchical centers located in the central nervous system, the so-called autonomic nervous system (ANS). Depending on the type and characteristics of exercise, one of two mechanisms may play a major role: 1) the central command starting from the cerebral cortex, or 2) peripheral modulation arising from the mechano-or chemoreceptors located in the heart, vessels and active muscles that transmit informations to the nucleus of the tractus solitarius in the medulla oblongata. The cardiorespiratory and metabolic responses of the variables during exercise depend on an interplay of severa! factors. This implies that research studies related to exercise must take ali ali of these into consideration. lt should be emphasized that the magnitude pf these variables strongly depends on the type of exercise, i.e., dynamic (isotonic) or static (isometric) exercise. EFFECTS OF MUSCLE STRENGTHENING AND PHYSICAL CONDITIONING IN REDUCING IMPAIRMENT AND DISABILITY IN CHRONIC STROKE SURVIVORS Teixeira-Salmela, Luci Fuscaldi, Ph.D., PT; Sandra Jean Olney, Ph.D.,PT; Sylvie Nadeau, Ph.D., PT, and Ian McBride, M.Sc. The purpose of this study was to investigate the impact of a combined program of muscle strengthening and physical conditioning in reducing impairment and disability in subjects with chronic stroke. A pre- and post-test control group design was employed with subjects stratified according to their walking speed, prior to randomization. Subjects were randomly assigned to control (n=7) and treatment (n=6) groups. The program was conducted for 10 weeks, three times weekly, immediately after baseline tests. After 10 weeks ali subjects were retested. The training program consisted of supervised exercise sessions with each session including a 5-10 minute warm-up, aerobic exercises such as graded walking, stepping, or cycling performed at a target heart rate of 70% of the maximal heart rate attained at the exercise testing, strengthening training exercises for the major muscle groups of the paretic lower limb, and a cool-down period. The effects of the intervention, as measured by the Human Activity Profile (HAP), the Nottingham Health Profile (NHP), and comfortable walking speed, were positive. Subsequently, after the second baseline measure, the control group underwent the same 10- week training program and were retested after intervention, in order to get a better estimation of the treatment effects. In addition to previous variables, measures of rate of stairclimbing, isokinetic strength of the major muscle groups of the affected lower limb, and spasticity of the knee and ankle joints were obtained. Full gait analyses were also employed to obtain temporal/distance, kinematic, and kinetic measures of the lower limbs. While the treatment and control groups did not differ at baseline, results of ANOV A showed significant improvements in ali selected variables only for the treatment group. In terms of overall treatment effects, the 13 subjects demonstrated increases in the isokinetic peak torque generated by the major muscle groups of the affected lower limb (42%), in functional performance, as determined by improvements in HAP

11 Rev. Bras. Fisiot. Suplemento Especial 17 scores (39%), comfortable walking speed (8 o/o), and rate stairclimbing (37%), as well as improvements o f 78% in quality o f life as determined by the NHP were observed without concomitant changes in either quadriceps anci/or ankle plantarflexor spasticity (p<0.007). In addition, significant improvements in walking pattern were observed, as determined by increases in selected kinematic measures and in joint moments. Furthermore, the subjects were able to generate higher leveis of power after training and demonstrated increases in positive work performed by the ankle plantarflexor and hip flexor/extensor muscles. In summary, a combined program of muscle strengthening and physical conditioning was shown to be beneficiai for subjects with chronic stroke. Participation in the exercise program.appeared to improve self-confidence and perceived abilities in chronic stroke subjects, and thus may be of value in maintaining independence in activities of daily living. AN APPROACH TO CEREBRAL PALSY BASED ON THE FAMILY Braga, Lúcia Willadino, Ass. das Pioneiras Sociais da Rede Sarah de Hospitais do Aparelho Locomotor, Brasília. The SARAR Network of Hospitais for the locomotor System, in the late 1970s, developed a methodology for treating children with cerebral palsy. This approach is based on family training. A treatment program elaborated by a multidisciplinary team, based on a prognostic objective evaluation with realistic goals to be achieved, is developd with the aim of incorporating the family's participation into every levei of the rehabilitation process. The method includes a great number of educational strategies, part of wich aim to teach the familyabout the pathology. Knowledgeabout the disease contributes towards rendering the family capable of possibility working with the child on the development of his/her motor, cognitive, and communication skills. The parent's training schedule and itinerary are structured to facilitate the learning process; among their activities are instructional meetings on the technical pathology onformation, daily activities with the child, and support groups with members of the multi-disciplinary team. This method has been improved and consolidated over the course of the last 18 years. Today it has extensive instrctional material including manuais and vídeos. The team employs computerized protocols, a gait analysis laboratory and a neuropsychology laboratory wich permit an even better oblective evaluation. Thus, the definition of goaals and program treatment are more clearly established in accordance with each patient's needs and capabilities. With the aim of evaluating the resultats of this method, two groups of children were studied. The first group (group A) partook of the method-oriented program, working in family participation; the second (group B) consisted of having the children submitted to treatment and stimulation by specialized professionals only (no family involvement). Each group consisted of children diagnosed with cerebral palsy, aged 1 to 6 years old. The motor and cognitive development of the children was carefully monitored and followed upon during throughout one year. The comparison between the two groups was conducted using qui-square and ultiple regression statistic tests. The resultats showed that the group which had worked with the family experienced better evolution in their motor and cognitive development, while the group that worked exclusively with professionals failed to present equally successful outcomes (p<o.ool). On the other hand, exercise training causes adaptations in ali biological systems. The nature and the extent of these adaptations depend on the characteristics of the training (type, frequency, intensity and duration) and of the physiological conditions o f the subjects submitted to this procedure. The physiological basis of risks and benefits of this procedure, as an approach for prevention and treatment of cardiovascular diseases, will be the object of this presentation. ANÁLISE DE MOVIMENTO COMO INSTRUMENTO DE AVALIAÇÃO DE RESULTADOS EM REABILITAÇÃO MOTORA Saad, Marcelo ; Linamara Rizzo Battistella; Danilo Masiero 1 -Divisão de Medicina de Reabilitação do HC-FMUSP 2- Disciplina de Fisiatria do DOT-UNIFESP-EPM, Centro de Reabilitação Lar Escola S. Francisco O movimento humano, em especial a marcha, é uma seqüência de fenômenos rápidos e complexos. É extremamente difícil, à observação clínica, analisar e quantificar seus desvios da normalidade. Tal situação levou à criação dos chamados Laboratórios de Movimento, que são estruturas equipadas para registro e análise interpretativa. A análise de movimento tem papel fundamental no tratamento das patologias do aparelho locomotor. Suas aplicações incluem: a-) identificação dos mecanismos causadores de padrões patológicos; b-) quantificação do afastamento da normalidade; c-) planejamento e direcionamento terapêutico (fisioterapia; bloqueios neuro-musculares; cirurgia, etc.); d-) comparação pré e pós-tratamento; e-) prescrição e adequação de órteses, próteses e auxiliares de locomoção; f-) documentação médico-legal Os campos da análise de movimento são: cinemática (estudo do movimento em si); cinética (estudos das forças envolvidas com o movimento); eletromiografia dinâmica (estudo do instante e da intensidade da contração muscular); gasto energético (avaliação do desempenho e eficiência do movimento). Para estudos nestes campos do conhecimento, a análise de movimento pode se valer de diversos recursos. Estes podem variar desde instrumentação simples como cronômetro, até sofisticados sistemas computadorizados de rastreamento automático do movimento. Em nosso país, a análise de movimento ainda é uma atividade de grandes centros tecnológicos, exercida por uma elite de pesquisadores. Porém, a literatura médica estrangeira tem documentado a importância deste exame para evitar maus resultados. Atualmente, muitas decisões terapêuticas (fisioterapia, ortetização I protetização, bloqueios químicos

12 18 Rev. Bras. Fisiot. Suplemento Especial neuromusculares, cirurgias) são tomadas baseadas em informações empmcas. Nos países desenvolvidos, os dados do Laboratório de Movimento tem papel importante e definitivo na tomada de decisões terapêuticas que envolvem a locomoção. Evidentemente, um Serviço de Saúde que conte com tal estrutura poderá oferecer um tratamento muito mais racional para patologias do aparelho locomotor, baseado em evidências mais concretas. Tal tratamento racional tem potencial de diminuir maus resultados, ocasionados em outras condições menos favoráveis. Um tratamento mau sucedido tem custos financeiros, sociais e humanos. Os dados do exame de movimento são informações a mais, que aumentam as chances de sucesso de um tratamento. NOVA ABORDAGEM NO TRATAMENTO DA LOMBALGIA- MÉTODO MCKENZIE DE DIAGNÓSTICO E TERAPIA MECÂNICA. Masselli, Maria Rita, Universidade Estadual Paulista, Presidente Prudente Robin McKenzie é um médico osteopata que desenvolveu um método de diagnóstico e tratamento da coluna Vertebral baseado no mecanismo de produção da dor - por acreditar que a grande maioria das disfunções da coluna são mecânicas e por isso podem ser tratadas de maneira mecânica. Mais importante do que isso, uma vez que os princípios sejam entendidos, a maioria dos tratamentos mecânicos podem ser realizados pelo próprio paciente. A base do método é combater as posturar erradas que o corpo assume nas diferentes atividades do nosso cotidiano - em casa e no trabalho. Então, o ponto principal do método é que o tratamento é responsabilidade do paciente e que será mais eficaz a longo prazo do que qualquer outra forma de tratamento. Este, inclui exercícios criteriosamente escolhidos, mobilizações e manipulações. As duas últimas técnicas só são utilizadas se e quando necessário. O método McKenzie vem suscitando grande interesse na comunidade científica e muitos trabalhos, que questionam o método ou que o endossam, têem sido publicados. Eu venho trabalhando com o método há 7 meses e os resultados são muito bons. STRA TEGIES OF MOTOR REHABILITATION: THE ROLE OF ADAPTIVE CHANGES Latash, Mark L., The Pennsylvania State University, University Park, PA 16802, USA Issue of Normality in Movement Coordination. "Normality" is a misnomer commonly used in clinicai movement studies. A person with a disorder of a subsystem involved in the production of voluntary movements may be expected to display atypical patterns of motor coordination. In particular, differences in apparent motor goals may lead to the generation of movements that may look clumsy to an observer who does not see the goals as they are seen by the actor's central nervous system (CNS). These atypical patterns may be viewed as optimal with respect to a certain group of motor tasks which this person considers important, if one takes into account the actual state of structures participating in movement production. These atypical motor patterns can hardly be viewed as "wrong" or "pathological" because they have been elaborated by the person's CNS based on its actual state and functional goals. Motor Redundancy and Atypical Motor Patterns (for review see Latash, Anson, 1996). Motor redundancy may be viewed as a source of complicated computational problems that the CNS needs to solve, or as a source of flexibility and adaptability which, in particular, allows humans to switch to alternative, atypical motor coordination strategies with respect to everyday motor tasks. So, probably we should start using "abundance" instead o f "redundancy". Although we do not know the criteria used by the CNS to make selections of motor patterns, we may assume that such criteria exist and that they are common for ali persons who belong to the general population and do not have highly specialized motor skills. These sets of coordinative rules that make choice possible may be called "CNS priorities". One may expect them to change following a major change (injury) of a subsystem participating in movement production or very specialized training. Optimization in Voluntary Movements (for review see Kawato, 1996). Optimization has been used as a method of solving the problem of redundancy in both robotics and motor control. A number of opmitization principies have been suggested based on minimization of such factors as energy expenditure, movement time, joint wear, discomfort, change in central command, etc. Ali these factors look rather artificial, however; it is more likely that movement optimization is based on functionally important factors that may reflect the actual state of the system for movement production and be task-specific. In this sense, crawling is an optimallocomotion pattern in babies but not in grown-ups. CNS Plasticity (see Merzenich et ai., 1984; Crepe) et ai., 1996). Plasticity is one of the most exciting and poorly understood features of the CNS. If one studies projections of certain groups of neurons onto other group of neurons, "maps" can be seen that are rather well reproducible across the general population. Recent studies have shown, however, that most, if not all of these maps are flexible and able to demonstrate a quick, major reorganization following a major change in the patterns of incoming signals. Such map modifications have been reported after specialized training or immobilization of effectors, after stroke, and after amputation. Neuronal mechanisms of plasticity have been studied in such brain structures as the hippocampus and the cerebellum and assumed to participate in processes underlying memory, in particular motor memory. This amazing ability of the CNS to "rewire itself' is Iikely to contribute to adaptive changes in motor coordination. Examples o f Motor Pathologies Amputation. Apparent immediate consequences of a limb amputation include changes in the limb biomechanics and in reflex projections. Plastic changes have been shown to leads to changes in cortical maps of neuronal projections. Among adaptive consequences documented in persons after leg amputation are changes in the role of muscle groups in the generation and absorption of energy and changes in postura) adjustments. Spinal Cord Injury. Apparent immediate consequences include blocked conduction along descending and ascending pathways and destroyed segmenta) neuronal apparatus. It has been hypothesized that adaptive consequences to a spinal cord

13 Rev. Bras. Fisiot. Suplemento Especial injury resulting in spasticity may include an increase in the number and affinity of receptors sensitive to inhibitory mediators (GABA). As a result, certain drugs (e.g., intrathecal baclofen) are highly effective in suppressing spasticity while voluntary movements may not be further suppressed or may even be unmasked. These adaptive changes may also be the reasons for the selective effects of baclofen on muscles of the left and right sides of the body in hemisyndromes. Parkinson's Disease. (for review see Rothwell, 1995). Apparent direct consequences include the lack of dopamine production by substantia nigra and malfunctioning of the cortex-basal ganglia-thalamus-cortex loop. One may speculate that some of the apparently abnormal motor patterns actually represent results of adaptive changes. These speculations should be viewed only as illustrations of the whole approach rather than viable hypotheses. Down Syndrome. No apparent neurological abnormality has been reported in persons with Down syndrome with the notable exception of reports of cerebellar impairment. These persons are characterized by the slowness in making decisions and low IQ. Adaptive consequence may include preference for safe motor patterns resulting in prolonged reaction time, long movement time, and co-contraction patterns of muscle activation. Implication for Rehabilitation. (for review see Latash, Anson, 1996). Patient's CNS is "aware" of the present status of different subsystems and of available motor strategies. Two factors may prevent the CNS from finding an optimal solution: Jacking predictive abilities and pain or discomfort. The therapist has an advantage of knowing possible long-term consequences of different therapeutic strategies. Different aspects in the role of a therapist can be emphasized: Teaching a person who demonstrates atypical, clumsy movements "correct movement patterns", or Providing assisting tools and directing adaptive processes so as to optimize functionally important behaviors. MOTOR REEDUCATION IN STROKE: WHAT IS LEARNED WHEN MOVEMENT IS TAUGHT? Levin, Mindy F. Rehabilitation Institute of Montreal, 6300 Darlington, Montreal, Quebec, Canada. Motor function following a stroke progresses from paralysis to the appearance of abnormal movement synergies to the ability to produce isolated movements of the limbs outside of the abnormal patterns of synergy. Sensorimotor function is also characterized by the inability to activate appropriate muscles and to coordinate movements between adjacent joints. Severa) mechanisms have been cited as leading to these motor impairments: decreased agonist muscle activation, lack of antagonist inhibition, altered mechanical properties of motor units, muscle weakness, and improper spatial and temporal muscle recruitment including inappropriate agonist/antagonist coactivation. Motor abnormalities are also related to deficits in the organization of segmenta! reflex activity like reciproca! inhibition, stretch reflex threshold regulation and abnormal postura) adjustments. Throughout the recovery process, therapeutic interventions are aimed at decreasing abnormally increased muscle tone and increasing the patient=s functional capacity. Although therapy stresses the importance of movement repetition over days or weeks to improve performance, what aspects and by what mechanisms performance improves is unclear. lt is also unclear whether improvement results from a 'normalization' or an 'adaptation' of motor output. Traditional physiotherapeutic stroke treatments range from those based on the neuro-developmental approach in which a hierarchically organized CNS is assumed, to behavioral approaches focussing on motor re-learning. In the latter approach, missing components of the movement are practised following detailed task analysis. This Apractise= approach in the rehabilitation of stroke patients is borrowed from the fundamental analysis of how healthy subjects acquire new motor skills. However, although based on sound theoretical considerations, to date there is little evidence that motor learning occurs in the same way in stroke patients as in healthy subjects. It is also unclear what movement parameters improve when the task or movement is repeatedly practised. Does practice lead to the restoration of the coordination patterns seen in healthy subjects or from the substitution of new compensatory patterns. To understand this fundamental problem, our research addresses the following questions: What specific characteristics of motor production are altered following CNS lesions? Do these characteristics change following treatment? Do these changes Jead to measurable functional improvement? These questions are addressed by comparing the characteristics of arm and trunk movements in hemiparetic subjects to those in healthy subjects and by analyzing the effects o f repeated practice o f the motor task on these characteristics. This comprehensive approach may lead to a better understanding of the mechanisms underlying motor deficits and recovery and to the development of more effective treatment methods for patients with movement disorders. ESTABLISHMENT OF COORDINATED MOVEMENTS DURING NORMAL EMBRYONIC DEVELOPMENT Bradley, Nina S., Ph.D., P.T., University of Southern California, Los Angeles. The framework for coordinated movement is established even as spinal motor neurons begin to activate their target muscles. One of the most frequently employed models for study of earliest motor behavior in vertebrates is the chick embryo. Overt movement in the chick is first observed at embryonic day (E) 3.5 and progressively increases in intensity, duration, ancl/or variety over the 21 days of development in ovo. First characterized by the eminent neurobiologist Viktor Hamburger, the predominant motor behavior observed in chicks over the course of embryonic development is referred to as type I motility. Type I motility is spontaneous and consists of activity sequences lasting a few seconds to 30 or more seconds. Between E4 and E15, the total amount of motility progressively increases as a result of both an increase in the duration of activity and a decrease in the duration of pauses interposed between the activity sequences. Beginning Ell, a second 19

14 20 Rev. Bras. Fisiot. Suplemento Especial behavior, type 11 motility is observed. Between E15 and E21, pauses between activity sequences increase and total amount of activity decreases. Starting E17 a third behavior, type III motility, is observed as the embryo prepares for hatching. Until recently it was believed that both types I and 11 motility were uncoordinated behaviors and type III motility was the first coodinated behavior emerging during development. For the past two decades investigators have speculated that the neural circuits within the spinal cord producing embryonic motility may be the same neurons that will eventually form the central pattern generator (CPG) for locomotion (for review see Bradley & Bekoff 1989). In large part this view was based on the findings that motor neuron output of embryonic spinal circuits exhibited many of the features common to those of isolated spinal cord preparations for study of locomotor generation in adult cat. Namely, at E9-El0, flexor and extensor motor neurons of the thoracolumbar spinal cord produce repetitive, alternating bursts associated with flexion and extension of the legs for multiple cycles equivalent to one activity sequence. Further, like the locomotor CPG, afferent and descending input are not required, for these alternating bursts can be recorded from cut dorsal roots in reduced spinal preparations with only 3-4 spinal segments intact. The primary difference between chick and cat spinal preparations is that the patterns recorded from the cat spinal cord include basic temporal features resembling those of intact locomotion, such as the asymmetry of flexor and extensor burst durations and linear scaling of extensor burst duration with cycle duration. In the chick embryo, the motor pattern recorded is generally a symmetric alternation of flexor and extensor bursting and is also different from that observed during locomotion after hatching. The view that embryonic motility is produced by an embryonic version of the locomotor CPG has recently come under question. Rather, it has been suggested that a transient spinal network produces spontaneous motility during initial development. This view has emerged in part because of evidence that in embryonic spinal circuits, as in other regions of the nervous system, inhibitory neurotransmitters initially have an excitatory effect. For example, glutamate-activated NMDA receptors, a fundamental element in locomotor CPG circuits, depend on the initial binding of glutamate to neighboring AMPA receptors for effective depolarizing of the neuron, but during early stages of development, the inhibitory transmitter, GABA, binding to GABAA receptors, substitutes for the slower developing AMPA receptors. The transient role of GABA may at least partially account for the spontaneous nature of embryonic motility. Inhibitory neural transmitters begin to exert inhibitory effects on spinal neurons during the latter half of embryonic development, and likely account for the progressive decline in amount of motility observed after E15. Based on severa! behavioral studies of embryonic motility, it is my view or hypothesis that even if the initial spinal circuitry in the embryo is transient, it is the foundation for development of coordinated movement. For example, multichannel EMG recordings indicate that flexor and extensor muscle synergies characterize type I motility at E9-El0 (Bradley & Bekoff 1990, 1992). Additionally, kinematic data demonstrate that leg and wing excursions are orderly, not random as previously believed, and the patterns of excursions are consistent with the muscle synergies obtained in EMG recordings (Chambers et ai. 1995). More specific, the kinematics reveal that joint excursions covary closely within a limb for the majority of cycles in an activity sequence at and concurrent excursions of the ipsilateral elbow and ankle are also loosely coupled at E9. We've hypothesized that previous studies failed to detect coordinated movement because they used direct visual observation methods. Because the embryo is buoyant up to approximately E15, there are insufficient reaction forces to stabilize its posture as it moves, thus the movement situation may be too complex for visual detection of coordinated movement. If amniotic fluid is removed to reduce the extent of buoyancy, coordination of movements is enhanced and more readily apparent during direct observation (Chambers et ai. 1995). Collectively, the studies indicate that intralimb and interlimb coordination are fundamental characteristics of movement within days after onset in the embryo. Given the extent of coordinated early movements and previous conflicting reports as to the eventual regression of type I motility, my lab has established methods for obtaining synchronized EMG and kinematic recordings for extended periods of spontaneous motility at severa! ages. We have begun to quantitatively determine the normal transformations in embryonic behavior leading to hatching at E21. Thus far we have analyzed data for comparisons of spontaneous motility at E9, E12 and E15. Our initial findings indicate that motility consists of coordinated and reliable features at each age. Intralimb coordination is progressively strengthened, where as interlimb coordination becomes more variable with increasing age as the limbs begin to exhibit more frequent instances of isolated movement. In addition to an increasing amount of activity between E9 and El5, there is a progressive decomposition in the timing of consecutive movements from the more regular repetitive joint excursions at E9 to the more irregular, frequently abrupt and ballistic excursions generated at E15 (Bradley 1998, Rose et ai. 1998). We are also in the process of examining variables that may contribute to the transformations in motility. Currently, we are testing whether the environment contributes to the behavioral transformations at one or more embryonic ages. To date, we have manipulated the environment within the egg at 4 different ages to constrain motion by either reducing the extent of buoyancy or by attaching an ankle splint. We selected to study the former test condition because buoyancy normally varies dramatically over the embryonic period, from a state of complete buoyancy to non-buoyancy near hatching. Our results suggest that a reduction in buoyancy, and increased exposure to gravitational and frictional forces can significantly alter the timing and amplitude of limb excursions, altering both intralimb and interlimb coordination (Bradley 1997). For example, a reduction in buoyancy increases co-variations for concurrent joint excursions within a limb (increased intralimb coordination) and decreases co-variations for concurrent excursions of ipsilaterallimbs (decreased interlimb coordination). We selected the second test condition because posture and joint motion are increasingly constrained as body size increases within the fixed volume of the egg. At younger ages the leg is slightly extended and force-unloaded; at!ater ages the leg is flexed, the foot

15 Rev. Bras. Fisiot. Suplemento Especial rests against the shell wall, and Ioading forces are generated through the limb during motility as the embryo attempts to extend from the cramped posture. Thus, we applied the ankle-foot orthosis to test whether generation of Ioading forces at ages earlier than hatching can modify movement patterns. Preliminary analyses indicate that not only does the constraint alter ankle motion, but ate 12, it also alters interlimb coordination o f the ipsilateral wing and Ieg. Thus, another current hypothesis is that mechanical forces arising from movement in ovo may contribute to the normal transformations in behavior. It is generally held that sensory information does not contribute significantly to the contrai of embryonic motility until the onset of hatching. Nonetheless, the chick emerges from the egg with the ability to produce an array of adaptive behaviors, such as walking, running, 1-leg stance, swimming, hopping, and scratching. Thus, our current efforts are directed toward eventually determining i f environment-dependent movement experiences during embryonic development contribute to the establishment of adaptive posthatching behaviors and whether deviations in embryonic movement experience impact normal development. The findings of such studies are expected to provide basic biological grounds for considering whether movement-dependent sensory information during fetal development contributes to early human motor behaviors. The potential implications of our work for rehabilitation of premature infants following Iesions of the central nervous system are generally impossible to propose at this time. One might speculate, however that very early insults, those interrupting neurogenesis, may prohibit the establishment of a foundation for coordinated movement, where as Iesions after neurogenesis is basically complete may be more amenable to therapeutic interventions. Our ultimate goal is to assist rehabilitation clinicians and scientists in the difficult task of determining if there are windows during early human development when treatment interventions for movement disabilities are more likely to be effective. REORGANIZAÇÃO TÔNICO-FÁSICA DA POSTURA: RESULTADOS PRELIMINARES Durigon, Odete de Fátima Saiias; Costa, M.T.Z., Curso de Fisioterapia da Universidade de São Paulo Com base no conhecimento produzido a partir do estudo das reações de equilíbrio ou "ao desequilíbrio" com auxílio de plataformas móveis que permitem deslocamentos lineares nos sentidos antero-posterior e latero-iateral bem como deslocamentos angulares com registro eletromiográfico simultâneo dos grupos musculares envolvidos no controle da postura, procedemos estudos no sentido de delinear um protocolo de intervenção terapêutica com a finalidade de reorganização/correção da postura. A utilidade do desenvolvimento de um novo procedimento é respaldada pela constatação de que os protocolos de intervenção com a finalidade corretiva baseiam-se e agem exclusivamente no sistema musculoesquelético desconsiderando o contexto neural de controle da postura e do equilíbrio que impõe aos músculos um padrão de atividade que será determinante na expressão postura!. Conseqüentemente suas ações e efeitos são limitados. Com base no que foi exposto estamos desenvolvendo protocolos de pesquisa clínica com o objetivo de delinear um programa de intervenção terapêutica preventiva/corretiva que integre os sistemas controlador (neural) e o controlado (musculoesquelético). A metodologia envolve duas etapas: I) organização da abordagem terapêutica baseada nos princípios descritos acima levando em conta os pressupostos para a validade do constructo e 2) aplicação desse protocolo em indivíduos, faixa etária 7 a 63 anos de ambos os sexos o que nos permitirá a longo prazo delinear a eficiência por faixa etária de 7 anos embora os resultados preliminares refiram-se a 45 indivíduos de 15 a 49 anos. A intervenção fisioterápica inclui posicionamento corretivo passivo/ativo progressivo no sentido distai-cranial com treino simultâneo de ajuste postura! tônico e fásico tanto em sedestação como no ortostatismo; treinamento de força, resistência e elasticidade dos músculos deficitários na forma de facilitação neuromuscular proprioceptiva e treino do equilíbrio através da utilização das estratégias de tornozelo, quadril e passo nos três planos espaciais. A evolução é controlada a cada sessão através de método fotográfico padronizado para a postura ortostática, nas vistas laterais, anterior e posterior com utilização de marcadores em pontos de referência anatômico padronizados pela literatura. As imagens são analisadas quanto à simetria, alinhamento segmentar, alinhamento em relação a linha de gravidade através de cálculos de ângulos e distâncias entre os pontos de referência os quais estão sendo analisados com técnica estatística descritiva e de inferência (MANO V A) comparando-se os dados obtidos antes e após a intervenção. A duração total da intervenção variou em função da complexidade das correções de cada indivíduo bem como do grau de desequilíbrio muscular encontrado, contudo fixou-se como mínimo um número de 10 sessões. O controle fotográfico diário nos permitirá estudar o padrão de evolução Os resultados preliminares indicaram melhora significativa (p<0,05) nos parâmetros controlados. Além disso as alterações mostraram-se consistentes já nas primeiras sessões. A NEW TECHNIQUE TO ASSESS MOTOR REHABILITATION AND DEVELOPMENT Surburg, Paul R., Indiana University, USA. This presentation will address the development and utilization of a neurological assessment technique which may be used in rehabilitation settings and as a research tool. This technique is closely linked with the attainment of a developmental milestone and involves an information paradigm. This milestone is midline crossing integration which usuaily is attained by 8 or 9 years of age (Stilwell, 1981). An inability to demonstrate this milestone is called midline crossing inhibition (MCI).While MCI has been identified with brain dysfunction (Head, 1920) and other disabilities in children and young adults (Wagner & Cisillo, 1968; Schofield, 1971), measurement procedures (Ayres, 1972) to identify MCI have been rudimentary in nature. Early in this decade Eason and Surburg (1993) developed a technique to assess MCI which involved the customary spatial factors but also included a temporal factor. Initially studies with this new technique evaluated individuais with mental disabilities and identified MCI with these developmentaiiy delayed subjects (Surburg,Johnston & Eason, 1994; Woodard & Surburg, 1994). At the time these studies 21

16 22 Rev. Bras. Fisiot. Suplemento Especial were published a new line of inquiry was initiated. Johnson and Surburg (1993) found that MCI is evident in persons 65 years and older. A subsequent study identified MCI in persons with Huntington's disease which involves aging at a more rapid rate. Both these studies incorporated a new application of the Eason and Surburg technique. Leg motions(woodard,lewis & Surburg, 1996) were used to identify MCI with these two populations. To date all research and test batteries, related to MCI,have used exclusively upper extremity movements. Lower extremity movements have been used to investigate neurological integrity after anterior cruciate surgery. Initial work is being conducted on validating this protocol for assessing different stages of Multiple Sclerosis. Finally the nuances of a new dependent measure, the MCI Index and recent advances, will be addressed in this presentation. REEDUCAÇÃO LOCOMOTORA Souza, Pedro Américo de, Escola de Educação Física da UFMG Após a alta médica e fisioterápica os portadores de comprometimentos locomotores, geralmente, apresentam marcha com qualidade aquém de suas reais possibilidades. Partindo da hipótese de que seria possível melhorar a capacidade locomotora de deficientes físicos nas condições expostas acima, há vinte anos SOUZA vem desenvolvendo e aplicando um método baseado em teorias do treinamento esportivo. Essa metodologia é sistematizada segundo princípios e teorias, tais como: periodização, estimulação proprioceptiva, sistema dinâmico de cargas, aplicação de tarefas motoras (educativos), estimulação motivacional. Visando a estruturação do programa de reeducação motora, foi estruturado, tanto um protocolo de avaliação quanto um repertório de cento e cinquenta (150) tarefas motoras, as quais são selecionadas com base motivacional (potenciais) ou com base nos objetivos de reeducação motora. Procura-se codificar padrões motores desejados e inibir padrões não desejados. A análise dos resultados obtidos em vinte anos de desenvolvimento e aplicação do método, em casos de paresia cerebral (hemiparesia, ataxia e atetose), nos permite conclusões como: a capacidade locomotora de deficientes físicos pode ser melhorada significativamente após a alta médica e fisioterápica, mesmo após transcorridos váriso anos; o método é adequado tanto para crianças capazes de seguir orientações verbais ou escritas quanto para adultos, podendo ser aplicado em hospitais, residências, clínicas ou academias com atendimento especializado em Educação Física adaptada. O método deverá dar sequência aos métodos Bobath, Kabat e Vojta, podendo ser aplicado concomitante aos mesmos. Seria desejável uma aplicação mais disseminada dessa metodologia, além de um controle estatístico. THE EFFECT OF EXERCISES ON HIP JOINT MOMENTS Kirkwood, Renata Noce1.2, Ph.D.; Elsie Culham 1 ' 3, Ph.D.; Patrick Costigan 2, Ph.D.; Department of Anatomy and Cell Biology 1, Clinicai Mechanics Group 2 and School ofrehabilitation Therap/, Queen's University, Kingston, Ontario, Canada. PURPOSE: Fractures o f the proximal femur are a result o f falls and low bone mass due to osteoporosis in the aging population. Exercise is a non-invasive method of treatment that is proposed to be of benefit in prevention of hip fractures by reducing bone loss. However, the appropriate exercise prescription has not been well established. It has been suggested that both intensity and diversity of stress are important in influencing bone remodeling. The purpose of this experiment was to measure the moments of force and rates of change in moments at the hip joint during thirteen selected exercises and compare with those obtained during levei walking. Knowledge of the net mechanical effect of walking, stair climbing and other exercises at the hip joint would allow the development of an exercise program designed to optimally increase femoral bone mass. SUBJECTS: Thirty healthy subjects, 17 male and 13 female, ranging in age from 55 to 75 years (mean: 65.2 years), participated in this study. The subjects had no history of osteoarthritis or pain at the knee and hip. METHODS AND MA TERIALS: Data from the right test hip was collected. The gait and exercise patterns were obtained using a 3D gait analysis system. The system includes an Optoelectronic motion tracking, a force plate, anthropometric information and standardized x-rays to calculate 3D components of the hip and knee joints. An inverse dynamic approach was used based on a co-ordinate system embedded in the proximal tíbia and femur along the posterior/anterior, lateral/media! and distal/proximal axis. The unique characteristic of the system is the radiographic procedure that provides precise control of subject positioning and correction of parallax error allowing a more accurate transformation from surface markers locations to joint centres of rotation. The exercises investigated included weight bearing activities (climbing stairs,!unge, knee bend, and single limb stance on the right limb while the left Iimb goes into flexion, extension and abduction) and non-weight bearing activities (single limb stance on the left limb while the right limb goes into flexion, extension and abduction). All subjects performed levei walking, 24 performed ascending stairs~ descending stairs and the remainder of the exercises was randomly assigned such that each exercise was performed by a mlnimal of 8 subjects. ANALYSIS: A two-way analysis of variance (ANOV A) with repeated measures on ali factors was carried out using the maximum peak moment and rate of change in moments obtained at the hip during the activities under investigation. In case of a significant F ratio, a paired T test was conducted to compare the mean difference between levei walking and each o f the exercises in every plane. RESUL TS: Descending stairs generated the highest hip moments of force (0.96Nrn/Kg) in th~ frontal plane, but not significantly higher than levei walking (0.91Nrn/Kg). In the sagittal plane, levei walking generated the highest moment of ali the exercises. The hip moments in the transverse plane obtained during ascending stairs (-0.21Nrn/kg/sec) was significantly higher than that obtained during levei walking (-0.11Nrn/Kg) (p < 0.05). The rates of change in moments in the frontal and transverse planes were higher during descending (0.111Nrn/Kg/sec) and ascending stairs ( Nrn/Kg/sec) respectively, but not significantly higher than those obtained during levei walking. In the sagittal plane, levei walking generated the highest rate of change in

17 Rev. Bras. Fisiot. Suplemento Especial moments. CONCLUSION: Of the thirteen exercises investigated none generated higher hip moments and rates o f change in moments than levei walking in ali three planes. Most of the exercises generated moments and rate of change in moments similar to or significantly lower than levei walking. It was concluded that levei walking could be combined with the exercises that generated moments and rate of change in moments comparable or greater than those obtained during gait in an exercise program designed to maintain or increase bone mass at the hip. The incorporation of these exercises would add both intensity and diversity o f the stress, which are important for maximal increase in bone formation. Acknowledgements: This work was supported by the Medicai Research Council of Canada, and CAPES, Brazilian Scholarship. NEW DIRECTIONS FOR REHABILIT A TION OF PERSONS WITH STROKE Olney, Sandra J., School of Rehabilitation Therapy, Queen's University, Kingston, Ontario, Canada. Stroke is the third leading cause of death and the primary cause of disability in the elderly in most industrialised nations. Those who survive more than 18 months have life expectancies comparable to those of the general age and sexmatched population. Treatment that is aimed at reducing disability should not only result in better quality of life, but also can be expected to reduce health care costs. A number of recent research findings have implications for treatment. Study of the biomechanics of gait in stroke has resulted in the identification and quantification o f the work and power contributions of the major muscle groups. This information has direct applications in physical therapy training methods, and has also been used in computerised training. Practitioners have frowned upon strengthening, as a method of reducing impairment for decades. However, recent research has demonstrated not only that the muscle groups of chronic stroke subjects can be strengthened, but that these gains are carried over into their gait. There is no evidence to date that strengthening is accompanied by changes in spasticity. Aerobic conditioning has not been considered for persons with stroke. Recent research suggests that aerobic conditioning and strength training combined, when carried out with appropriate screening, produces large improvements in health status and reduction in disability. RESTORA TION OF PROPRIOCEPTION AND NEUROMUSCULAR CONTROL IN THE UNSTABLE KNEE AND SHOULDER OF A THLETES Lephart, S., Neuromuscular Research Laboratory, Program of Sports Medicine, Department of Orthopaedic Surgery, University o f Pittsburgh, Pittsburgh, Pennsylvania, USA. Injury to capsuloligamentous structures of the knee and shoulder compromises both the static and dynamic restraining mechanisms of joint. While the primary role of articular structures is to guide skeletal segments providing static restraint, they contain mechanoreceptors which mediate the dynamic restraint of the rotator cuff muscles. As this articulation is minimally constrained, such a coordinated dynamic mechanism about the joint is necessary for stability during arm motion. Our series of studies (Lephart, et ai. J Shoulder Elbow Surgery, 3: , 1994) revealed that with shoulder instability from cumulative injury to the capsuloligamentous structures there is a loss of proprioceptive feedback which may reduce the reflexive muscular protection against excessive humeral head translation. Further theses studies demonstrated that following surgical stabilization these deficits in proprioception were eliminated. This retensioning of the mechanical restraining structures improved the sensory transmission from the joint and thus may provide a basis for normal kinematics and the dynamic protective mechanism necessary for upper extremity activity. Reestablishing functional stability in the absence of surgical stabilization necessitates rehabilitative techniques designed to produce adaptations is the sensitivity of peripheral afferents (capsuloligamentous and tenomuscular) and facilitation of afferent pathways resulting in enhanced muscle coactivation and restoration of discriminatory activation. A DYNAMICAL APPROACH TO LOCOMOTION IN CHILDREN WITH HEMIPLEGIC SPASTIC CEREBRAL PALSY Fonseca, Sérgio T., Kenneth Holt, Linda Fetters and Elliot Saltzman, Depto. de Fisioterapia e Terapia Ocupacional, UFMG. Patterns of locomotion observed in children with spastic cerebral palsy have long been interpreted as a failure of normal neural maturation. In contrast to this view, we propose that the atypical walking pattern in spastic cerebral palsy could involve kinematic and morphological adaptations that allow these children to successfully accomplish the task. Analysis of the dynamic resources available to these individuais might explain why children with spastic cerebral palsy do not develop the typicallocomotor pattern of non disabled children. Two studies were developed according to the dynamical systems theory. The observed walking patterns produced by children with spastic cerebral palsy were interpreted as functional adaptations to the neurological impairment. In the first study, locomotion was modeled as an inverted pendulum with springs and a phase dependent forcing function. The springs represented the stiffness provided by muscles and connective tissue. A forcing function was included to represent the periodic concentric muscular actions during the push-off phase of gait. This allowed us to relate the dynamics guided by Newtonian equations of motion to the observed gait patterns. In the secorid study, we investigated how muscular forces and elastic energy work to maintain locomotion in real musculoskeletal systems. The objective of the second study was to explore how the dynamic requirements of the task and the dynamic action capabilities of the children with cerebral palsy relate to specific kinematic and mechanical energy patterns o f their gait. 23

18 24 Rev. Bras. Fisiot. Suplemento Especial Kinematic data of children with cerebral palsy and matched non-disabled children were collected at five different walking speeds. The data were related to the dynamic parameters of the modelos equation of motion. Results indicated that the model was successful in describing locomotion, showing that both children with cerebral palsy and non-disabled children conform to the dynamics of escapement driven pendulum mass spring system. In addition, group and within subject leg differences in terms of system stiffness, forcing function, vertical stiffi.ess, landing angle of the center of mass about the ankle joint, and mechanical energy parameters of the center of mass indicated that children with spastic hemiplegic cerebral palsy assumed a gait dynamics similar to a composite inverted pendulum on the non affected limb and a pogo stick on the affected limb. It was concluded that the kinematic details and functional adaptations observed in children with cerebral palsy during walking resulted from the interplay between the dynamical capabilities of the individual and task requirements. When learning to walk, children with cerebral palsy will make use of available dynamic capabilities in order to produce the desired action. Lack of one or more parameters, such as strength, may lead to atypical pattern organization. VOLUNTARY MOVEMENT AS A PERTURBATION TO BALANCE: POSTURO-KINETIC CAPACITY IN THE ABLE-BODIED AND THE DISABLED Bouisset, Simon, Laboratoire de Physiologie du Movement, Université de Paris-Sud Antecipatory postura! adjustments (APA) assocated with intentional movement have been studied in both bilateral and unilateral upper limb flexions, performed without and with an added inertia. Three methods were used simultaneously (electromyography, accelerometry, force platform). The results have shown that APA are specific to the characteristics of the forthcoming intentional movement. Their finality has been argued on the basis of a simple biomechanical analysis: they tend to create inertial forces which, when the time comes, will counterbalance the disturbance ofbalance dueto the forthcoming intentional movement. In this context, the inteentional movement is considered as a perturbation to balance. The concept of dynamic asymmetriy has been proposed to characterize this factor, which depends not only on the parameters of movement (such as its velocity), but also on its location with respect to the body's axes of symmetry. Moreover, in order to take into account the ability to react efficiently to the forthcoming perturbation, the concept of posturo-kinetic capacity (PKC) has been proposed. PKC has been supposed to depend on the actual state of the sensori-motor system, for example on impairments in trauma or disease. With the aim to check this hypothesis, PKC has been assessed in parkinsonians and in paraplegics, with reference to able-bodied subjects. In paraplegics (T4 levei, fully rehabilitated patients), AP A were almost doubled, whereas movement velocity was significantly decreases. In parkinsonians (patients with severe tremor aand marked L-Dopa-induced dyskinesia were excluded), there were neither APA nor specificity, and movement velocity was drastically slower. Velocity reduction in both impairments can be explained by the patients inability to counterbalance the perturbing forces which would have been associated with faster movements. Possible biomechanical and neurophysiological causes of PKC lessening are discussed. ROLE OF THE AGONIST AND ANTAGONIST MUSCLES IN RAPID MOVEMENT PERFORMANCE Jaric, Slobodan, Institute for Medicai Research, Bel grade, Yugoslavia e Motor Control Laboratory, University of Campinas, Brazil The agonist muscles are usually considered responsible for kinematics of the movement they initiate. It has been often reported that an increase in the agonists' strength, or power caused by either athletic training or therapeutic procedure improves the performance of the movement they perform (Jelusic et ai. 1992; Kramer et ai. 1993). However, a number of studies have shown that the antagonist muscles also demonstrate a prominent EMG activity, particularly while performing rapid, self-terminating movements (Mustard & Lee, 1987; Gottlieb et ai. 1989). The temporal pattern of the recorded activity also suggested an important role of the agonist and antagonist muscles in providing acceleration and deceleration torque, respectively. As a consequence, it could be assumed that, in addition to agonists, the ability of antagonists to exert force could also be o f importance for performance o f rapid, discrete movements. In order to assess the role of agonists and antagonists in movement performance we applied severa! experimental factors assumed to affect muscles' ability to exert force (Jaric et ai. 1995, 1997, 1998a, 1998b). Specifically, subjects performed rapid, consecutive elbow flexion and extension movements between two targets prior to and after (i) strengthening elbow extensors, (ii) fatiguing elbow flexors, and (iii) fatiguing elbow extensors. In addition, some movements were performed with an externai torque applied in a way to either assist or resist the tested movements. The results generally demonstrated similar velocity of flexion end extension movements despite the large difference in the strengths of elbow flexors and extensors. Movement velocity was also similarly affected when the experimental factors (i.e., strengthening or fatiguing procedure) were applied on agonists and antagonists. Fatiguing of agonists and antagonists was associated with a decrease in net muscle torque during the acceleration and deceleration phase, respectively (see Fig. 1). Finally, the results also demonstrated consistent changes in the symmetry ratio (i.e., acceleration time divided by deceleration time). Namely, movement time was redistributed in a way to provide more time for action of the muscle group with relatively reduced ability to exert the force dueto the applied experimental factor (i.e., strengthening, fatiguing, or applying an externai torque). Taken together, the results obtained (i) stress the importance of action of both the agonist and antagonist muscles, and (ii) particularly emphasize their mechanical role in limb acceleration and deceleration, respectively, while performing

19 Rev. Bras. Fisiot. Suplemento Especial rapid, discrete movements. Although the applied approach does not let us to discern roles o f the central and peripheral factors in the studied phenomenon (c.f., Enoka, 1994), as well as to assess particular roles of potentially important muscle mechanical properties (e.g., muscle strength, power, rate of force development; c.f., Wilson & Murphy, 1996), the results obtained could be of importance for application in physical therapy, physical education, and other kinesiologically related disciplines. For example, the application of standardized mono-articular tests of the agonist muscles in order to asses movement performance have been often questioned (Mero et ai. 1981; Jaric et ai 1989; Baker et ai. 1994). We believe that an involvement of the antagonist muscles (in addition to agonists) could improve both the validity and the predictional power of this approach. In addition, either training or therapeutic procedures applied on antagonists could be associated with an improvement in movement performance in a similar way as the same procedures applied on the agonist muscles. Acknowledgements: This work was supported by a grant of Serbian Research Foundation and by a grant of FAPESP (97\ ), Brazil. HOW SHOULD NEW TREA TMENTS BE CRITIQUED FOR SCIENTIFIC MERIT? Harris, Susan R., PhD, PT, FAPTA; Professor, School ofrehabilitation Sciences, University ofbritish Columbia, Vancouver, B.C., V6T 2B5, CANADA. PURPOSE: Like many other health professionals, physical therapists and other rehabilitation providers often have a tendency to adopt, and sometimes to enthusiastically embrace, new treatment approaches that have not been subjected to adequate scientific scrutiny. Many recent therapy approaches are extremely controversial and offer little, if any, theoretical or empírica) support for their effectiveness. Goals ofthis presentation are: 1) to introduce participants to characteristics which typify "non-standard" or controversial therapies; and 2) to provide specific criteria for evaluating a new (or existing) treatment approach. RELEV ANCE: This presentation will provide specific objective cri teria that can be used to guide rehabilitation professionals in judging the effectiveness and scientific credibility of the services that they provide. DESCRIPTION: Eight characteristics that typify "non-standard" therapies, as outlined by Golden (1980), will be presented first. These include, for example, "lack of confirmation by well-designed, randomized, controlled studies", "rapid, uncritical acceptance by the public", and "no harmful side effects" (Golden, 1980). Each characteristic will be accompanied by examples of controversial treatments that have been described in the non-professional rehabilitation literature. Secondly, six specific criteria for evaluating the scientific merit of a new treatment approach will be described. Participants will be advised to apply these criteria when contemplating whether or not to use a new treatment with their clients or when deciding whether or not to enroll in a treatment-oriented continuing education course based on a new approach. And finally, eight objective criteria for evaluating the efficacy of a new (or existing) treatment will be presented. These criteria are modified from guidelines developed by the U.S. Federal Drug Administration for evaluating the efficacy of new drugs. OBSERVA TIONS: This paper was initially presented at the First Annual Catherine Worthingham Fellows Forum in 1993 at the APTA Annual Conference in Cincinnati, Ohio. The topic engendered some lively debate and comments from the audience and resulted in a number of requests from physical therapy faculty and clinicians to obtain the written script for the presentation. Portions of the paper were also presented as part of a 90-minute presentation at the CP AI APTA Congress in Toronto in J une, The paper was subsequently published as an article in Physical Therapy in February, 1996*. CONCLUSIONS: The scientific credibility of both new and existing treatment approaches is a topic that should be of paramount importance to ali rehabilitation professionals. As health care providers, we have an ethical responsibility to our clients to provide treatments that are theoretically-sound and that are supported by well-controlled, randomized clinicai trials. Likewise, the proponents of new (and existing) treatment approaches are responsible for scientifically documenting the efficacy of those treatments. It is hoped that this presentation will foster such scrutiny among rehabilitation practitioners and will provide them with objective cri teria for evaluating the validity of new and existing therapy interventions. *Harris SR. How should treatments be critiqued for scientific merit? Physical Therapy. 1996;76: DEVELOPMENT OF A FUNCTIONAL MOTOR SCALE FOR INFANTS BASED ON CONTEMPORARY MOTOR CONTROL THEORY Campbell, Suzann K., PhD, PT, FAPTA, Depart ofphysical Therapy, University ofiiiinois at Chicago, Chicago, IL, USA Although most therapists and many physicians believe that intervention begun early for infants with deviant motor performance is more effective than!ater treatment, early identification of children who might benefit from intervention suffers from lack o f valid diagnostic and functional motor scales. Although a new assessment of General Movement developed by Prechtl and colleagues shows promise as a diagnostic tool, no functional motor scale exists for use by physical therapists and occupational therapists for identifying delayed development, planning treatment, and documenting outcomes. In this presentation, a new motor performance scale, the Test of Infant Motor Development (TIMP), is described which is based on 1) clinicai knowledge and results of qualitative research on postura) and selective control of movement needed for functional activities in infants from 32 weeks postconceptional age through 4 months post-term, and 2) a contemporary model of motor control and development which emphasizes the role of multiple interacting subsystems and constraints in the person, as well as the role of the environment and task characteristics, in performance of functional motor skills. Functional skills are defined to be those movements which infants use to react to the demands of handling by caregivers and to initiate postura! adjustments or self-comforting, exploration o f the environment, or social interaction. Research on the test h as been conductect on more than 200 infants. 25

20 26 Rev. Bras. Fisiot. Suplemento Especial The TIMP consists of 59 items organized into 2 scales, the Observed Scale (28 dichotomously rated items scored on the basis of spontaneous movements of the infant) and the Elicited Scale (31 items rated on 5-, 6- or 7-point hierarchical scales) which captures infants' responses to movement "problems" posed by the examiner. The Observed Scale contains items reflecting important qualitative aspects of movement that may be diagnostic of conditions such as cerebral palsy, as well as selective contrai of individual joints, head centering, and antigravity control of the body and limbs. The Elicited Scale is based on assessment of the infant's response to being placed in a variety of positions in space and being presented with challenges to postura! contrai such as rotation of a body part, presentation of visual or auditory stimuli, or being moved in space, including elicitation of lateral righting reactions of the head, body, and limbs. ltems on the Elicited Scale have been shown to be similar to movement challenges posed by caregivers during typical interactions such as bathing, dressing, and play. Item reliability, test-retest reliability, and rater scoring reliability are each above Test scores increase significantly with increasing chronological age and decrease in the presence of greater numbers of medicai complications reflecting risk for developmental disability. Longitudinal assessment o f more than 30 infants from the age at which they became medically stable enough to be tested through 4 months adjusted age demonstrated linearly increasing scores, and infants ranging in age from 32 weeks postconceptional age through 4 months post-term can be divided into 5 distinct leveis of ability. Current research is investigating the predictive validity of the TIMP to 6-, 9- and 12-month performance on the Alberta Infant Motor Scale and the test's discriminative ability for documenting differences in longitudinal developmental curves of children with brain insults, chronic lung disease, extreme or moderate prematurity, and those born full-term with no medicai complications. Future plans include a study to develop norms for performance at various ages which can be used to identify children with delayed gross motor development. When complete, the TIMP will be useful for therapists as well as for physicians and nurses implementing and studying a variety of interventions aimed at improving the outcomes o f infants at high risk for developmental disabilities. THE INFLUENCE OF SUPPORT INSTABILITY ON POSTURAL REACTIONS TO MUSCLE VIBRA TION T ALIS V.L., IV ANENKO Y.P., KAZENNIKOV O. V., Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia. lt is known that the vibration of Achilles tendons elicits backward movement of the body. This effect was considered a result of muscle shortening dueto an "error signal" about muscle length to CNS. But the error signal of muscle length didn't explain why neck muscle vibration induced forward whole-body inclination. Many studies of last decades testified to the evidence of context dependent nature of vibratory reactions, emphasising the functional role of muscle being stimulated. Here we studied the influence of support instability on postura! responses to muscle vibration in healthy humans. The vibration of neck dorsal muscles and Achilles tendons was applied during equilibrium maintenance on movable rocking supports (seesaw) of different curvatures capable of performing a translational-rotational movement (rolling) in a sagittal direction. The directional dependence o f vibration-induced reactions was the same as on the rigid floor: backward body displacement during Achilles tendon vibration and forward body displacement during neck muscle vibration. Neck muscle vibration on the movable support provoked a quick initial forward body sway. This initial quick response was absent on the rigid floor. The decrease of support stability (dueto the increasing of seesaw curvature) diminished significantly the effect of Achilles tendon vibration and in a lesser extent the effect of neck muscle vibration. The results suggest that postura! responses to muscle vibration reflect peculiarities o f participation o f different postura! muscles in the control o f human upright posture and depend on the state of the system of equilibrium maintenance. The difference in the magnitude and in the initial component of reactions could indica te a functional meaning o f proprioceptive input. During balancing on the movable support the vestibular system plays a particularly important role in the equilibrium maintenance. This is consistent with neurological reports to the data that patients with absent vestibular function cannot keep balance on seesaws. Specific features of postura! responses to neck muscle vibration during unstable posture support the hypothesis that the interpretation o f proprioceptive signals from the neck occurs in the context of vestibular signals of head movement. Supported by Russian Foundation ofbasic Research, grant # ATIVIDADE MOTORA ADAPTADA: QUANDO COMPREENDER O 'DIFERENTE' FAZ A DIFERENÇA. Pedrinelli, Verena Junghahnel, Prof. Ms., Departamento de Educação Física, Universidade São Judas Tadeu Atender as necessidades individuais e assegurar o sucesso é antiga premissa na atuação profissional que envolve os programas de atividades motoras. Compreender o potencial de desenvolvimento do portador de (d)eficiências constitui fator preponderante para o ótimo desempenho na relação profissional-participante. A abrangência de conhecimentos é vasta e é necessária competência para analisar, sintetizar e relacionar os conhecimentos para estruturar as atividades levando em consideração as limitações motoras da clientela envolvida. As últimas décadas têm, mais do que nunca, revolucionado em termos dos conhecimentos produzidos e a velocidade de acesso às informações provoca mudanças de comportamento dos profissionais para garantir a atualização e compreensão dos fenômenos. Baseados nesta perspectiva, o objetivo da presente proposta é destacar que estudos recentes (Latash & Anson, 1996; Manoel, 1997) evidenciam que o desenvolvimento da pessoa portadora de (d)eficiência não é atrasado, limitado ou inexistente, mas é diferente. A partir da questão "Enfim, o que está por trás de rebater uma bola", serão (a) apontados os conhecimentos relevantes para a formação de profissionais em educação física adaptada I atividade motora adaptada; e (b) destacados alguns aspectos relevantes do processo ensinoaprendizagem na deficiência mental, considerando aspectos do desenvolvimento cognitivo e da percepção; e (c) apresentada a