Clinical Neuroscience

[Modeling of human movements, neuroprostheses]


JULY 20, 2011

Clinical Neuroscience - 2011;64(07-08)

[Modeling of human movements became very important as modern methods in informatics and engeniering are available to discern human movement characteristics that were hidden before. The construction of models of neural control and mechanical execution of human movements helps the diagnosis of movement disorders and predicts the outcome of clinical intervention and medical rehabilitation. Here I present methods for recording kinematic and muscle activity patterns. Measurements can be compared with predicted movement patterns based on mathematical models. There are an infinity of different muscle activity patterns or joint rotation patterns to perform a given motor task. I present the main approaches that are used to find such solutions from the infinity of choices that might be employed by the central nervous system. I present a practical application of movement modeling: In rehabilitation of spinal cord injured patients we develop and apply artificially controlled neuroprostheses to generate active cycling lower limb movements in the patients of the National Institute for Medical Rehabilitation.]



Further articles in this publication

Clinical Neuroscience

[Recent changes in the paradigm of limbic encephalitis]


[In the recent years, novel antibodies associated with limbic encephalitis have been described, which target such extracellular receptors or proteins that have been already indicated in the pathogenesis of hereditary or degenerative diseases. In a number of cases, where pathogenic role of antibodies generated against the voltage-gated potassium channel (VGKC) had been presumed, antibodies against a trans-synaptic scaffolding protein, LGI1 were indicated. Antibody response against NMDA-receptors has been suggested as a major cause of limbic encephalitis especially in young females, resulting in a typical clinical syndrome sometimes triggered by an ovarian teratoma. Antibodies against other receptors essential in synaptic transmission and plasticity (AMPA and GABAB receptors) have been also indicated, partially elicited by paraneoplastic processes. Such antibodies against surface proteins result in severe but potentially treatable diseases due to reversible internalization of the antigens crosslinked by the bivalent antibodies. In contrast, the rare classical onconeural antibodies reacting with intracellular targets (anti-Hu, anti-Ta/Ma2, anti- CV2/CRMP5) may elicit additional symptoms beside limbic encephalitis and the prognosis of such syndromes is poor.]

Clinical Neuroscience

[Our first impact factor: 0.236 (2010)]

RAJNA Péter, TAJTI János

Clinical Neuroscience

[Extension of polynomial analysis of interstitial I-125 brachytherapy for 48 months]


[Objective - Previously we described from 20 patients’ data with our new “polynomial prediction approach” the volumetrical changes following gliomas I-125 brachytherapy. The aim of this study is to extend the polynomials for 48 months, and to carry out multivarial analysis of several different aspects. Methods - 20 inoperable low-grade gliomas were followed for a 48-month period after I-125 interstitial irradiation. The delivered dose on the tumor surface was 50-60 Gy. Dose planning and image fusion were done with the BrainLab Target 1.19 software, mathematical and statistical computations were carried out with the Matlab numeric computation and visualization software. Volumes of tumor necrosis, reactive zone and edema referred to as “triple ring” were measured on image fused control MRI and planning CT images. The measured volumes were normalized with respect to the reference volumes. Mean values of volumes were determined, then polynomials were fitted to the mean using the polynomial curve fitting method. The accuracy of our results was verified by correlating the predicted data with the measured ones. Results - We have found that the edema reaches its maximum two times after irradiation during the 48 months follow up period. We have shown that small tumors react more rapidly and creating greater volumes of the “triple ring” than bigger ones. Conclusions - The polynomial prediction approach proposed here reveals the dynamics of triple ring for 48 months. The derived polynomials and the multivarial analysis carried out afterwords help to (i) design the best treatment, (ii) follow up the patient's condition and (iii) plan reirradiation if necessary.]

Clinical Neuroscience

[Phylo- and ontogenetic aspects of erect posture and walking in developmental neurology]

BERÉNYI Marianne, KATONA Ferenc, CARMEN Sanchez, MANDUJANO Mario

[The group or profile of elementary neuromotor patterns is different from the primitive reflex group which is now called the “primitive reflex profile.” All these elementary neuromotor patterns are characterized by a high degree of organization, persistence, and stereotypy. In many regards, these patterns are predecessors or precursors of from them the specific human motor patterns which appear spontaneously later as crawling, creeping, sitting, and walking with erect posture. On the basis of our experiences it can be stated that the elementary neuromotor patterns can be activated in all neonates and young infants as congenital motor functions. With regards to their main properties and functional forms, the normal patterns can be divided into two main groups: (1) One group is characterized by lifting of the head and complex chains of movements which are directed to the verticalization of the body; (2) The other group is characterized by complex movements directed to locomotion and change of body position. The neuromotor patterns can be activated by placing the human infant in specific body positions that trigger the vestibulospinal and the reticulospinal systems, the archicerebellum and the basal gangliae. Most of these systems display early myelinisation and are functioning very soon. Many of the elementary neuromotor patterns reflect the most important - spontaneously developing - forms of human movements such as sitting upright in space and head elevation crawling and walking. The majority of the human neuromotor patterns are human specific. When the infant is put in an activating position, crawling, sitting up, and walking begin and last as long as the activating position is maintained. Each elementary neuromotor pattern is a repeated, continuous train of complex movements in response to a special activating position. The brainstem is not sufficient to organize these complex movements, the integrity of the basal ganglia is also necessary. Elementary sensorimotor patterns during human ontogenesis reflect phylogenetic develpoment of species specific human functions. During ontogenesis spontaneous motor development gradually arises from these early specific sensorimotor predecessors.. The regular use of the elementary neuromotor patterns for diagnostic puposes has several distinct advantages. The neuromotor patterns have a natural stereotypy in normal infants and, therefore, deflections from this regular pattern may be detected easily, thus, the activation of the elementary neuromotor pattern is a more suitable method for identifying defects in the motor activity of the neonate or young infant than the assessment of the primitive reflexes. The “stiumulus positions,” which activate specific movements according to how the human neonate or young infant is positioned, do not activate such motor patterns in neonate or young primates including apes. The characteristic locomotor pattern in these adult primates, including the apes, is swinging and involves brachiation with an extreme prehensility. This species specific motor activity is reflected in the orangutan and gibbon neonates by an early extensive grasp. However, according to our investigations, no crawling, creeping, elementary walk, or sitting up can be activated in them. Neonates grasp the hair of the mother, a vital function for the survival of the young. In contemporary nonhuman primates including apes, the neonate brain is more mature. Thus, pronounced differences can be observed between early motor ontogenesis in the human and all other primates. The earliest human movements are complex performances rather than simple reflexes. The distinction between primitive reflexes and elementary neuromotor patterns is essential. Primitive reflexes are controlled by the brainstem. All can be activated in primates. These reflexes have short durations and contrary to elementary sensorimotor patterns occur only once in response to one stimulus, e.g., one head drop elicits one abduction-adduction of the upper extremities correlated to adduction and flexion of the lower extremities to a lesser degree with the Moro reflex. Elementary neuromotor patterns are much more complex and most of them including elementary walk may be elicited as early as the 19th-20th gestational week, though less perfectly than later.]

Clinical Neuroscience

[Combined evoked potentials in co-occuring attention deficit hyperactivity disorder and epilepsy]

MAJOR Zoltán Zsigmond

[Background and purpose - Evoked potentials, both stimulus related and event related, show disturbances in attention deficit-hyperactivity disorder and epilepsies, too. This study was designed to evaluate if these potentials are characteristically influenced by the presence of the two diseases, individually, and in the case of co-occurrence. Methods - Fourty children were included, and four groups were formed, control group, ADHD group, epilepsy group and a group with the comorbidity of epilepsy and ADHD. Epilepsy patients were under proper antiepileptic treatment; ADHD patients were free of specific therapy. Brainstem auditory evoked potentials, visual evoked potentials and auditory P300 evaluation were performed. Results - The latency of the P100 and N135 visual evoked potential components was significantly extended by the presence of epilepsy. If ADHD was concomitantly present, this effect was attenuated. Brainstem auditory evoked potential components were prolonged in the presence of the comorbidity, considering the waves elicited in the brainstem. P300 latencies were prolonged by the presence of co-occurring ADHD and epilepsy. Feedback parameters showed overall reduction of the tested cognitive performances in the ADHD group. Conclusion - Disturbances produced by the presence of ADHD-epilepsy comorbidity reveal hypothetically a linked physiopathological path for both diseases, and offers an approach with possible diagnostic importance, combined evoked potential recordings.]

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Clinical Neuroscience

[Rehabilitation possibilities and results after neurosurgical intervention of brain tumors ]

DÉNES Zoltán, TARJÁNYI Szilvia, NAGY Helga

[Objectives - Authors examined the rehabilitation possi­bi­lities, necessities, and results of patients after operation with brain tumor, and report their experiences. Method - Retrospective, descriptive study at the Brain Injury Rehabilitation Unit, in National Institute for Medical Rehabilitation. Patients - Patients were admitted consecutively after rehabilitation consultation, from different hospitals, following surgical intervention of brain tumors, between 01 January 2001 and 31 December 2016. Patients participated in a postacute inpatient rehabilitation program, in multidisciplinary team-work, leaded by Physical and Rehabilitation Medicine specialist included the following activities: rehabilitation nursing, physical, occupational, speech, psychological and neuropsychological therapy. Results - At the rehabilitation unit, in the sixteen-year period 84 patients were treated after operation with brain tumor. Patients arrived at the unit after an average of 41 days to the time of the surgical intervention (range: 10-139 days), and the mean length of rehabilitation stay was 49 days (range: 2-193 days). The mean age of patients was 58 years (20-91), who were 34 men and 50 women. The main symptoms were hemiparesis (64), cognitive problems (26), dysphagia (23), aphasia (16), ataxia (15), tetraparesis (5), and paraparesis (1). The mean Barthel Index at the time of admission was 35 points, whereas this value was 75 points at discharge. After the inpatient rehabilitation, 73 patients improved functionally, the status of 9 patients did not show clinically relevant changes, and 2 patients deteriorated. During the rehabilitation 10 patients required urgent interhospital transfer to brain surgery units, 9 patients continued their oncological treatment, two patients continued rehabilitation treatment at another rehabilitation unit, and after rehabilitation 73 patients were discharged to their homes. Conclusions - Inpatient rehabilitation treatment could be necessary after operation of patients with brain tumor especially when functional disorders (disability) are present. Consultation is obligatory among the neurosurgeon, rehabilitation physician and the patient to set realistic rehabilitation goals and determine place and method of rehabilitation treatment, but even at malignancies cooperation with oncological specialist also needed. Authors’ experience shows benefits of multidisciplinary rehabilitation for patients after brain tumor surgery. ]

Clinical Neuroscience

[The complex intensive care and rehabilitation of a quadriplegic patient using a diaphragm pacemaker]

FODOR Gábor, GARTNER Béla, KECSKÉS Gabriella

[A 21 year female polytraumatized patient was admitted to our unit after a serious motorbike accident. We carried out CT imaging, which confirmed the fracture of the C-II vertebra and compression of spinal cord. Futhermore, the diagnostic investigations detected the compound and comminuted fracture of the left humerus and femur; the sacrum and the pubic bones were broken as well. After the stabilization of the cervical vertebra, a tracheotomy and the fixation of her limbs were performed. She spent 1.5 years in our unit. Meanwhile we tried to fix all the medical problems related to tetraplegia and respiratory insufficiency. As part of this process she underwent an electrophysiological examination in Uppsala (Sweden) and a diaphragm pacemaker was implanted. Our main goal was to reach the fully available quality of life. It is worth making this case familiar in a wider range of public as it could be an excellent example for the close collaboration of medical and non-medical fields.]

Clinical Neuroscience

[New opportunities in neuro-rehabilitation: Robot mediated therapy in conditons post central nervous system impairments]

FAZEKAS Gábor, TAVASZI Ibolya, TÓTH András

[Decreasing the often-seen multiple disabilities as a consequence of central nervous system impairments requires broadening of the tools of rehabilitation. A promising opportunity for this purpose is the application of physiotherapy robots. The development of such devices goes back a quarter of century. Nowadays several robots are commercially available both for supporting upper and lower limb therapy. The aim is never to replace the therapists, but rather to support and supplement their work. It is worthwhile applying these devices for goal-oriented exercises in high repetition, which one physically fatiguing for the therapist or for the correction of functional movement by various strategies. Robot mediated therapy is also useful for motivation of the patient and making the rehabilitation programme more versatile. Robots can be used for assessment of the neuromotor status as well. Several clinical studies have been executed in this field, all over the world. Meta-analyses based on randomized, controlled trials show that supplementing the traditional physiotherapy with a robot-mediated component presents advantage for the patients. Further studies are necessary to clarify which modality and intensity of the exercises, in which group of patients, in which stage lead to the expected outcome.]

Clinical Neuroscience

[Results of intrathecal baclofen therapy on spasticity in patients with brain injury]

DÉNES Zoltán, KLAUBER András, BOTH Béla, ERÕSS Loránd

[Objectives - To evaluate the results of intrathecal baclofen (ITB) therapy on the spasticity in patients with brain injury. Method - Retrospective study in Brain Injury Rehabilitation Unit between January 2001 and December 2010. Results - During the last ten years, in our unit 13 patients were involved into ITB therapy on severe spasticity, after brain injury, while more than 100 Baclofen pumps were implantated in Hungary with Hungary with coordination of the Multidisciplinary Team. ITB therapy was indicated in severe spasticity developed after seven cases of traumatic brain injuries, five cases of strokes and one case of anoxic brain injury. The mean age of patients was 26 years (18- 52). At the time of pump implantation three patients were in vegetative state. The shortest period elapsed between the brain injury and pump implantation was three months and the longest period was nine years, mean 15 months. Baclofen pump had to be changed in six cases after six years, and was removed in three cases due to decreasing spasticity. Catheter revision was performed in two cases due to flow problem. We had no complication in association with ITB therapy. Conclusions - Intrathecal baclofen therapy seems to be an effective and safe treatment in patients with severe spasticity of cerebral origin. We suggest team (neurosurgeon and rehabilitation professionals) decision in a spasticity center before involving the patient into ITB therapy, and follow up in the rehabilitation unit. The severity of spasticity as a consequence of brain injury can change during years and it is necessery to follow it with dosage and dynamics of baclofen therapy. Baclofen pump removal is suggested if the ITB therapy is further not reasonable.]

Clinical Neuroscience



[Introduction - Viscoelastic parameters of circumferential and meridional strips of ruptured and silent aneurysms were investigated (considered clinical and histological data either) in order to advance the prediction of risk of aneurysm rupture. Method - In our clinical practice, aneurysms managed by microsurgery aneurysm clipping were removed. Meridional and circumferential strips were cut. Strips were investigated by an uniaxial biomechanical instrument: distending force was recorded as the length of the strips was increased in steps. Normal stress-relaxation patterns were detected. The shape of strain curves well overlapped with the Standard Linear Solid Model curve, as had been expected. The viscosity, serial and parallel elastic moduli of the model were then computed. Results - Linear correlation was demonstrated amongst peek distending force detected and aneurysm strip thickness. Steric inhomogenity was detected at the meridional and circumferential strips. Strain-stress behaviour of ruptured and silent aneurysm specimen showed significant difference. Values of strips originated from patients suffered from hypertension as well as strips originated from aneurysms had been histologically found inflamed were higher. Discussion - Results of these observations are going to be used to set three dimensional computer model in cooperation with IT team of Budapest University of Technology and Economics to advance rupture risk prediction.]