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1.
Dev Neurorehabil ; 22(7): 479-486, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30332545

RESUMEN

Purpose: To elucidate the association between developmental stage of human figure drawing(HFD) and fine motor control, visual perception, and further investigate its potential to be used for screening developmental delay. Methods: Participants were 301 children at 5½ years of age, 176 born preterm and 125 at term, whose HFDs were categorized into six developmental stages. Motor-Free-Visual-Perception Test, Movement-ABC, Performance Intelligence Quotient (PIQ: Wechsler Scale), and the Visual-Motor Integration test were used. Fine motor functions were explored using ImageJ. Results: Age-expected HFDs were drawn by 87% of the children, while 13%, mostly preterm boys, drew immature ones. Stages of HFD were related to both PIQ and Movement-ABC. Visuomotor control and visual perception significantly explained the HFD. The sensitivity and specificity of HFD as a screening tool was moderate to good. Conclusions: HFD is influenced by visual perception and visuomotor control and can be used for screening developmental delay at preschool age.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Cuerpo Humano , Niño , Femenino , Humanos , Inteligencia , Masculino , Movimiento , Percepción Visual , Escalas de Wechsler
2.
Child Care Health Dev ; 44(4): 562-571, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29532497

RESUMEN

BACKGROUND: The Pediatric Evaluation of Disability Inventory (PEDI) has been recommended as a gold standard in paediatric rehabilitation. A Ugandan version of PEDI (PEDI-UG) has been developed by culturally adapting and translating the original PEDI. The aim of this study was to investigate the psychometric properties of the PEDI-UG in Ugandan children by testing the instrument's rating scale functioning, internal structure, and test-retest reliability. METHODS: Two hundred forty-nine Ugandan children (125 girls) aged 6 months to 7.5 years (Mean = 3.4, SD = 1.9) with typical development were tested using the PEDI-UG. Forty-nine children were tested twice to assess test-retest reliability. Validity was investigated by Rasch analysis and reliability by intraclass correlation coefficient. RESULTS: The PEDI-UG domains showed good unidimensionality based on principal component analysis of residuals. Most activities (95%) showed acceptable fit to the Rasch model. Six misfit items were deleted from the Functional Skills scales and one from the Caregiver Assistance scales. The category steps on the Caregiver Assistance scales' rating scale were reversed but functioned well when changed from a 6-point to 4-point rating scale. The reliability was excellent; intraclass correlation coefficient was 0.87-0.92 for the domains of the Functional Skills scales and 0.86-0.88 for the domains of the Caregiver Assistance scales. CONCLUSION: The PEDI-UG has good to excellent psychometric properties and provides a valid measure of the functional performance of typically developing children from the age of 6 months to 7.5 years in Uganda. Further analysis of all items, including misfit and deleted items, in children with functional disability is recommended.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Evaluación de la Discapacidad , Traducciones , Cuidadores/psicología , Niño , Preescolar , Discapacidades del Desarrollo/psicología , Discapacidades del Desarrollo/rehabilitación , Niños con Discapacidad/psicología , Niños con Discapacidad/rehabilitación , Femenino , Humanos , Lactante , Masculino , Psicometría/normas , Reproducibilidad de los Resultados , Uganda
3.
Child Care Health Dev ; 44(4): 552-561, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29527735

RESUMEN

BACKGROUND: The Pediatric Evaluation of Disability Inventory (PEDI) was developed and standardized to measure functional performance in American children. So far, no published study has examined the use of the PEDI in sub-Saharan Africa. This study describes the adaptation, translation, and validation process undertaken to develop a culturally relevant PEDI for Uganda (PEDI-UG). METHOD: The cross-cultural adaptation and translation of the PEDI was performed in a series of steps. A project manager and a technical advisory group were involved in all steps of adaptation, translation, cognitive debriefing, and revision. Translation and back-translation between English and Luganda were performed by professional translators. Cognitive debriefing of two subsequent adapted revisions was performed by a field-testing team on a total of 75 caregivers of children aged 6 months to 7.5 years. RESULTS: The PEDI-UG was established in both English (the official language) and Luganda (a local language) and comprises 185 items. Revisions entailed deleting irrelevant items, modifying wording, inserting new items, and incorporating local examples while retaining the meaning of the original PEDI. Item statements were rephrased as questions. Seven new items were inserted and 19 items deleted. To accommodate major differences in living conditions between rural and urban areas, 10 alternative items were provided. CONCLUSIONS: The PEDI-UG is to be used to measure functional limitations in both clinical practice and research, in order to assess and evaluate rehabilitative procedures in children with developmental delay and disability in Uganda. In this study, we take the first step by translating and adapting the original PEDI version to the culture and life conditions in both rural and urban Uganda. In subsequent studies, the tool's psychometric properties will be examined, and the tool will be tested in children with developmental delay and disability.


Asunto(s)
Comparación Transcultural , Discapacidades del Desarrollo/diagnóstico , Evaluación de la Discapacidad , Niños con Discapacidad , Traducciones , Niño , Preescolar , Discapacidades del Desarrollo/psicología , Niños con Discapacidad/psicología , Niños con Discapacidad/estadística & datos numéricos , Femenino , Humanos , Lactante , Masculino , Psicometría , Reproducibilidad de los Resultados , Población Rural , Uganda/etnología , Población Urbana
4.
AJNR Am J Neuroradiol ; 36(1): 181-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25169928

RESUMEN

BACKGROUND AND PURPOSE: Diffusion-weighted MR imaging and fiber tractography can be used to investigate alterations in white matter tracts in patients with early acquired brain lesions and cerebral palsy. Most existing studies have used diffusion tensor tractography, which is limited in areas of complex fiber structures or pathologic processes. We explored a combined normalization and probabilistic fiber-tracking method for more realistic fiber tractography in this patient group. MATERIALS AND METHODS: This cross-sectional study included 17 children with unilateral cerebral palsy and 24 typically developing controls. DWI data were collected at 1.5T (45 directions, b=1000 s/mm(2)). Regions of interest were defined on a study-specific fractional anisotropy template and mapped onto subjects for fiber tracking. Probabilistic fiber tracking of the corticospinal tract and thalamic projections to the somatosensory cortex was performed by using constrained spherical deconvolution. Tracts were qualitatively assessed, and DTI parameters were extracted close to and distant from lesions and compared between groups. RESULTS: The corticospinal tract and thalamic projections to the somatosensory cortex were realistically reconstructed in both groups. Structural changes to tracts were seen in the cerebral palsy group and included splits, dislocations, compaction of the tracts, or failure to delineate the tract and were associated with underlying pathology seen on conventional MR imaging. Comparisons of DTI parameters indicated primary and secondary neurodegeneration along the corticospinal tract. Corticospinal tract and thalamic projections to the somatosensory cortex showed dissimilarities in both structural changes and DTI parameters. CONCLUSIONS: Our proposed method offers a sensitive means to explore alterations in WM tracts to further understand pathophysiologic changes following early acquired brain injury.


Asunto(s)
Lesiones Encefálicas/patología , Parálisis Cerebral/patología , Tractos Piramidales/patología , Lesiones Encefálicas/complicaciones , Parálisis Cerebral/etiología , Niño , Estudios Transversales , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Masculino
5.
Phys Occup Ther Pediatr ; 33(2): 163-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23369068

RESUMEN

The aim is to describe the development of hand function in young adults with unilateral cerebral palsy (CP), who participated in a 2-week Constraint Induced Movement Therapy (CIMT) camp 6 years earlier. Eleven participants, 16-21 years at follow-up, were assessed at three occasions during 2005 and once in 2011. At the 6-year follow-up, performance on the Assisting Hand Assessment and the Jebsen-Taylor Hand Function test remained unchanged (P > 0.05) from the first assessment before the camp. Grip strength (Grippit®) increased in both the involved (+80.9%) and non-involved hand (+94.4%) (P < 0.05), while performance on the Melbourne Assessment tended to decrease (-7%). In conclusion, it seems that young adults with unilateral CP maintain their hand function performance at the same level as in the early adolescent period. Interestingly, the grip strength increased over time also for the involved hand.


Asunto(s)
Parálisis Cerebral/fisiopatología , Parálisis Cerebral/rehabilitación , Técnicas de Ejercicio con Movimientos , Mano/fisiopatología , Hemiplejía/fisiopatología , Restricción Física , Adolescente , Adulto , Análisis de Varianza , Parálisis Cerebral/complicaciones , Niño , Femenino , Estudios de Seguimiento , Fuerza de la Mano , Hemiplejía/etiología , Humanos , Masculino , Adulto Joven
6.
Neurology ; 77(8): 775-83, 2011 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-21832221

RESUMEN

UNLABELLED: Diffusion MRI improves detection of abnormalities in white matter tracts in cerebral palsy (CP). Relationships between diffusion measurements and hand function are largely unexplored. We aimed first to assess microstructure of corticofugal fibers, and second to explore associations between tract injury as assessed by quantitative analysis of diffusion MRI and hand function in children with unilateral CP. METHODS: In this cross-sectional study, 15 children with unilateral CP (6 boys, median age 12.4 years, min 7.2, max 17) and 24 controls were included (9 boys, median age 12.7 years, min 8.8, max 17.3). Hand function was assessed with the Box and Blocks (B&B) test. Magnetic resonance diffusion data (b value = 1,000 s/mm(2), 45 directions) were collected on a 1.5-T scanner. Fractional anisotropy (FA), mean diffusivity (MD), and tensor eigenvalues were measured bilaterally in the cerebral peduncle (ROI1), the posterior limb of the internal capsule (PLIC, ROI2), and corticofugal fibers connecting these regions. RESULTS: In children with CP, FA in both ROIs and the partial tract corresponding to the affected hand was significantly lower compared to controls. This was caused by an increase in diffusivity perpendicular to the tract. After controlling for age, mean FA contralateral to the affected hand correlated with B&B scores, which was independent of lesion type or number of voxels in the partial tract, cerebral peduncle, or PLIC. CONCLUSIONS: FA in corticofugal fibers is a sensitive marker of damage to the motor system and correlates with hand function in CP. Using FA may improve early prediction of outcome.


Asunto(s)
Mapeo Encefálico , Parálisis Cerebral/patología , Imagen de Difusión por Resonancia Magnética , Lateralidad Funcional/fisiología , Mano/fisiopatología , Fibras Nerviosas Mielínicas/patología , Adolescente , Anisotropía , Corteza Cerebral/patología , Parálisis Cerebral/fisiopatología , Niño , Estudios Transversales , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Vías Nerviosas/patología , Estimulación Luminosa/métodos , Puente/patología , Estadística como Asunto , Estadísticas no Paramétricas
7.
J Hand Surg Am ; 33(8): 1337-47, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18929198

RESUMEN

PURPOSE: To describe aspects of hand function in a total population of children with cerebral palsy (CP). METHODS: Upper extremity data were collected for 367 children who were born between 1992 and 2001 and were registered in a population-based health care program for children with CP. Hand function was classified according to the Manual Ability Classification System (MACS), the House functional classification, and the Zancolli classification. The type of spastic thumb-in-palm deformity was evaluated according to House. RESULTS: In the total population of children with CP aged 4 to 14 years, 60% had more than minor problems with hand function (>MACS I). Independence in age-relevant, daily manual activities (MACS I-II) was noted in 87% of children with spastic unilateral CP and in 63% of children with spastic bilateral CP, but in only 20% of children with dyskinetic CP. According to the House functional classification, both hands were spontaneously and independently used in 55% of children (House 7-8), whereas 5% did not use either of their hands (House 0). Minor increase of flexor muscle tone (Zancolli level 1) was found in 69% of all children. Only 2% were in level 3 in both hands. Spastic thumb-in-palm deformity in 1 hand was found in 25% and in both hands in another 15%. CONCLUSIONS: Limitations in hand function are common in all types of CP, but characteristics of the disability vary considerably between different CP subtypes. The MACS classification is useful to evaluate how well children can handle objects in daily activities. The House functional classification describes grip function in each hand separately; the Zancolli classification of finger and wrist extension and the classification of thumb-in-palm deformity according to House give an estimate of dynamic spasticity. All these classifications were shown to be useful in a population-based health care program, but further studies of the psychometric properties are required.


Asunto(s)
Parálisis Cerebral/complicaciones , Parálisis Cerebral/rehabilitación , Atención a la Salud/organización & administración , Deformidades Congénitas de la Mano/rehabilitación , Destreza Motora , Adolescente , Factores de Edad , Parálisis Cerebral/clasificación , Niño , Preescolar , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Deformidades Congénitas de la Mano/etiología , Articulaciones de la Mano/fisiopatología , Fuerza de la Mano , Humanos , Lactante , Estudios Longitudinales , Masculino , Espasticidad Muscular/fisiopatología , Vigilancia de la Población , Rango del Movimiento Articular , Sistema de Registros , Medición de Riesgo , Suecia , Análisis y Desempeño de Tareas
8.
J Hand Ther ; 20(3): 262-72; quiz 273, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17658420

RESUMEN

The aim of this qualitative study was to explore the experiences of young persons using their hemiplegic hand in daily life activities following upper extremity surgery (UES). Ten persons, aged 12-24 years, were interviewed individually five to seven years after surgery. The analysis was guided by a comparative method. The findings show that the participants during this period had experienced changes which they related both to the treatment and to development. Data resolved into three main themes. Functional improvements are interwoven into daily life, the hand is easier to use and is used more, and changes in the appearance and in the internal feeling of the arm are of importance. This study reflects the patients' experiences of living with the outcome of UES and yields an important complement to objective, quantitative outcome studies.


Asunto(s)
Parálisis Cerebral/fisiopatología , Mano/fisiopatología , Hemiplejía/cirugía , Evaluación de Resultado en la Atención de Salud , Extremidad Superior/cirugía , Actividades Cotidianas , Adolescente , Adulto , Niño , Estética , Femenino , Estudios de Seguimiento , Mano/cirugía , Fuerza de la Mano/fisiología , Hemiplejía/fisiopatología , Humanos , Masculino , Satisfacción del Paciente , Extremidad Superior/fisiopatología
9.
Clin Rehabil ; 21(1): 47-55, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17213241

RESUMEN

BACKGROUND: Goal-directed training is an activity-based approach to therapy. Meaningful, client-selected goals are used to provide opportunities for problem solving and to indirectly drive the movements required to successfully meet the task demands. This is in contrast to interventions that focus on changing body functions. Here, the principles of goal-directed training will be studied through two case studies with the aim of linking theories of treatment to clinical practice. PRINCIPLES ILLUSTRATED: The approach is based on the dynamic systems motor control theory and occupation-based therapy models, which suggest that movement patterns emerge from the interaction between the person's abilities, environment and the goal. Motor learning principles are applied to structure and schedule practice. THEORY IN PRACTICE: Four components provide the basis for goal-directed training: (1) selection of a meaningful goal; (2) analysis of baseline performance; (3) intervention/ practice regime; and (4) evaluation of outcome. Two individuals with acquired brain injury practised self-care tasks: eating and tying hair into a ponytail. Intensive training was undertaken over four weeks and the intervention outcome measured using the Goal Attainment Scale. CONCLUSIONS: The positive achievements in the self-care tasks illustrated that theories of motor control and motor learning can be applied to goal-directed training. The examples demonstrated that the approach could be applied to individuals with a range of abilities.


Asunto(s)
Actividades Cotidianas , Lesiones Encefálicas/rehabilitación , Objetivos , Hipoxia Encefálica/rehabilitación , Evaluación de Resultado en la Atención de Salud/métodos , Lesiones Encefálicas/psicología , Femenino , Humanos , Hipoxia Encefálica/psicología , Persona de Mediana Edad , Rehabilitación/métodos
10.
Acta Paediatr ; 94(4): 479-88, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16092464

RESUMEN

AIM: To study psychosocial adjustment and mental health in children with upper-limb reduction deficiency and a myoelectric prosthetic hand. METHODS: Sixty-two parents of children aged 8 to 18 y old answered a questionnaire concerning competence and behaviour/emotional problems in their children. Of the 62 children, 37 adolescents aged 11 to 18 y old answered questionnaires concerning competence, problems and mood state. The results were compared with Swedish normative data. The children were divided into five groups based on degree of myoelectric prosthetic use. RESULTS: Children with upper-limb reduction deficiency and a myoelectric prosthetic hand showed social competence and behaviour/emotional problems similar to Swedish standardized norms. However, withdrawn behaviour was significantly higher in all children, social competence was significantly lower in girls, and social activities were significantly lower in older children with upper-limb reduction deficiency. There was a significant difference between prosthetic use groups. Non-users had significantly more delinquent behaviour problems than full-time users. There was an interaction between gender and prosthetic use in their affect on competence and behaviour/emotional problems, yielding two contrasting patterns. CONCLUSION: Children with upper-limb reduction deficiency and a myoelectric prosthetic hand are as well adjusted psychosocially as their able-bodied peers. There are indications, however, of social stigmata related to the deficiency, which have to be considered differently in boys and girls.


Asunto(s)
Miembros Artificiales , Ajuste Social , Deformidades Congénitas de las Extremidades Superiores/psicología , Adolescente , Factores de Edad , Niño , Depresión , Femenino , Humanos , Delincuencia Juvenil , Masculino , Prótesis e Implantes , Factores Sexuales , Encuestas y Cuestionarios , Suecia
11.
Dev Med Child Neurol ; 42(11): 728-36, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11104343

RESUMEN

Mirror movements in individuals with hemiplegic cerebral palsy (CP) may result from a reorganization of the central sensorimotor system. Motor performances of both hands were measured to characterize mirror activity (or mirroring) and hand functions in 22 participants (6 to 18 years) with hemiplegic CP and in 17 control participants. During a unimanual repetitive squeezing task, contractions of the active hand and fingertip forces of the opposite hand were recorded simultaneously. In the control group, slight mirror activity (or mirroring) was found that decreased with age. In participants with CP, mirror activity was 15 times stronger than in the control group, and was found at all age levels. Mirroring was more prominent in the unaffected hand of the CP group. The amount of mirror activity was not related to the degree of hemiplegia, which was assessed with measures of spasticity, strength, and dexterity. Mirror movements disturbed functional bimanual skills, although to some extent they could be suppressed by voluntary effort.


Asunto(s)
Parálisis Cerebral/fisiopatología , Hemiplejía/fisiopatología , Destreza Motora , Adolescente , Niño , Femenino , Lateralidad Funcional , Mano/fisiología , Hemiplejía/etiología , Humanos , Masculino
12.
Dev Med Child Neurol ; 42(8): 545-53, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10981933

RESUMEN

The aim was to investigate the performance of children with attention-deficit-hyperactivity disorder (ADHD) in tasks involving motor-memory representations. A special grip object recorded forces generated by the fingertips during a precision grip-lift task. Common objects were lifted from a linear scale. Twenty-five boys with ADHD were evaluated and grouped according to the presence (ADHD+) or absence (ADHD) of movement dysfunction using the Movement Assessment Battery for Children (Henderson and Sugden 1992). Mean group ages were 11.4 years (range 9.0 to 11.0 years) and 11.7 years (9.0 to 15.6 years), respectively. They were compared to a control group of 25 age-matched boys, mean group age 11.8 years (range 9.0 to 13.0 years). Variability of motor performance was predominant in the ADHD+ group. Several of these participants presented a higher grip-force output during the gripping movement. They also had difficulties in adapting the motor output to target different weights, suggesting deficient anticipatory parameter control based on memory representations. The results suggest that in some children motor problems are due to detrimental neural control functions rather than core symptoms of ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Fuerza de la Mano/fisiología , Memoria , Trastornos de la Destreza Motora/etiología , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Niño , Femenino , Mano/inervación , Humanos , Masculino , Trastornos de la Destreza Motora/fisiopatología , Factores Sexuales , Análisis y Desempeño de Tareas
13.
J Nutr ; 130(9): 2207-14, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10958814

RESUMEN

Differences in glycemic responses to various starchy foods are related to differences in the rate of starch digestion and absorption. In this study, the importance of the degree of gelatinization and the product thickness for postprandial glycemic and insulinemic responses to rolled oats and barley were studied in healthy subjects (5 men and 5 women). Thick (1.0 mm) rolled oats were made from raw or preheated (roasted or steamed) kernels. In addition, thin (0.5 mm) rolled oats were made from roasted or roasted and steamed (processed under conditions simulating commercial production) oat kernels. Finally, steamed rolled barley kernels (0.5 or 1.0 mm) were prepared. All thin flakes elicited high glucose and insulin responses [glycemic index (GI), 88-118; insulinemic index (II), 84-102], not significantly different from white wheat bread (P: > 0.05). In contrast, all varieties of thick oat flakes gave significantly lower metabolic responses (GI, 70-78; II, 58-77) than the reference bread (P: < 0.05). Thick barley flakes, however, gave high glucose and insulin responses (GI, 94; II, 84), probably because the botanical structure underwent more destruction than the corresponding oat flakes. We conclude that minimal processing of oat and barley flakes had a relatively minor effect on GI features compared with the more extensive commercial processing. One exception was thick oat flakes, which in contrast to the corresponding barley flakes, had a low GI.


Asunto(s)
Avena , Glucemia/efectos de los fármacos , Pan , Carbohidratos de la Dieta/metabolismo , Manipulación de Alimentos/métodos , Hordeum , Insulina/sangre , Adulto , Glucemia/metabolismo , Rastreo Diferencial de Calorimetría , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/farmacología , Ayuno/metabolismo , Femenino , Humanos , Masculino , Periodo Posprandial
14.
Dev Med Child Neurol ; 42(4): 228-34, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10795560

RESUMEN

Recent studies on hand motor control in children with cerebral palsy (CP) have focused on the coordination of fingertip forces during the grasping and lifting of objects. However, little is known about the ability to replace and release an object from grasp, a function that is just as important for fine dexterity. The present study examines the coordination of fingertip forces during the replacement and release of an object (either 200 g or 400 g) from grasp in 14 children (aged between 7 and 13 years) with hemiplegic CP and in 14 age-matched typically developing children. The results indicate that children with hemiplegic CP abruptly replaced the object but had a prolonged and uncoordinated release of the grasp. Unlike what was seen in the control children, the grip and load forces decreased sequentially in the children with CP. However, all the children could appropriately scale the rate of force decrease based on somatosensory weight-related information from the ongoing lift. The results provide further information about the impaired hand skills in children with hemiplegic CP.


Asunto(s)
Parálisis Cerebral/fisiopatología , Fuerza de la Mano/fisiología , Hemiplejía/fisiopatología , Destreza Motora/fisiología , Adolescente , Parálisis Cerebral/diagnóstico , Niño , Femenino , Hemiplejía/diagnóstico , Humanos , Masculino , Examen Neurológico , Soporte de Peso/fisiología
15.
J Agric Food Chem ; 47(12): 5093-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10606578

RESUMEN

Pure and mixed films of alpha- and omega-gliadins were studied by tapping mode atomic force microscopy (AFM). The technique was sensitive to the chemistry of the surface properties of the films, allowing imaging of the mixed gliadin phases at different ratios. In addition to the study of the phases at the micrometer level, higher resolution images allowed visualization of the protein films at the molecular level. These studies may have relevance to the formation of phases in developing protein bodies in grain, where gliadins and glutenins are deposited together. It has been assumed that the protein bodies consist of a random network of proteins; these studies indicate that microphases could be present in protein bodies. The technique provides novel methods for studying mixed biopolymer systems.


Asunto(s)
Gliadina/química , Microscopía de Fuerza Atómica
17.
Brain ; 122 ( Pt 6): 1157-68, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10356067

RESUMEN

Children with spastic hemiplegia have impaired dexterity in the affected extremity. The purpose of the present study was to investigate whether the force co-ordination pattern during precision grip in 13 children between 4 and 10 years of age with predominant unilateral brain lesions is related to manual dexterity and to the location and size of the brain lesion. The force co-ordination pattern was investigated by means of a specially designed object that monitored the isometric fingertip forces applied to the contact surfaces during precision grip. Hand function was measured by means of neurological examination, functional hand-grips and dexterity. Brain lesions were identified by series of ultrasound and MRI scans. Normally, the fingertip forces are applied to the object in the initial phase of the lift in an invariant force co-ordination pattern (i.e. grip-lift synergy), in which the grip and load forces are initiated simultaneously and increase in parallel with unimodal force rate trajectories. A majority of children with unilateral brain lesions had not developed the force co-ordination pattern typical for their age, but produced an immature or a pathological pattern. The developmental level of the grip-lift synergy was determined and quantified according to criteria derived from earlier studies on normally developed children. There was a clear relationship between the developmental level of the grip-lift synergy and impaired dexterity, indicating that proper development of the force co-ordination pattern is important for skilled hand function. The grip-lift synergy correlated with the total extent of lesions in the contralateral cortex and white matter and with lesions in the thalamus/basal ganglia, while no correlation was found for isolated cortical lesions. The results suggest that the neural circuits involved in the control of the precision grip are organized in a parallel and distributed system in the hemispheres, and that the basal ganglia are important during the formation of these circuits. Perinatal lesions in specific cortical motor areas may be compensated for by circuits elsewhere in the grip-lift motor system, while large lesions exclude this possibility.


Asunto(s)
Encéfalo/patología , Fuerza de la Mano/fisiología , Hemiplejía/fisiopatología , Destreza Motora/fisiología , Mapeo Encefálico , Corteza Cerebral/patología , Niño , Preescolar , Lateralidad Funcional , Mano , Hemiplejía/patología , Humanos , Imagen por Resonancia Magnética , Examen Neurológico , Tiempo de Reacción
18.
Dev Med Child Neurol ; 40(9): 612-21, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9766739

RESUMEN

Thirty-two children with hand dysfunction due to cerebral palsy were examined before tendon transfer and muscle release, and 9 months postoperatively. All children improved their performance regardless of the degree of impaired hand function. The main advantage of surgery was a more functional position of the hand with increased wrist extension and forearm supination. There were also increased functionality of handgrips, grip strength, and dexterity. Impaired sensibility before surgery did not influence the outcome. Individual goals were set preoperatively. Individual functional goals outlined before surgery were met by most children. Children identified as having mild impairments gained new functional skills related to everyday activity (self-care and leisure), while children with severely impaired hand function demonstrated enhanced grasping ability, as well as a better cosmetic appearance.


Asunto(s)
Parálisis Cerebral/cirugía , Deformidades Congénitas de la Mano/cirugía , Destreza Motora , Músculo Esquelético/cirugía , Complicaciones Posoperatorias/fisiopatología , Transferencia Tendinosa , Adolescente , Adulto , Parálisis Cerebral/fisiopatología , Niño , Femenino , Estudios de Seguimiento , Deformidades Congénitas de la Mano/fisiopatología , Fuerza de la Mano/fisiología , Humanos , Masculino , Destreza Motora/fisiología , Músculo Esquelético/fisiopatología , Rango del Movimiento Articular/fisiología , Tacto/fisiología , Resultado del Tratamiento
19.
Dev Med Child Neurol ; 40(1): 4-11, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9459211

RESUMEN

One hundred and five children with the whole spectrum of obstetric brachial plexus (OBP) injuries, from severe to full recovery, were examined at the age of 5 years with regard to motor and sensory functions as well as to use of the affected limb. Since root involvement level does not fully reflect the degree of disability, a classification based on range of motion and grip-strength was formulated and found to correspond well with functional abilities. The results from this study indicate that the eventual outcome in upper-plexus lesions is more complex than is commonly believed. Hand function is affected due to the effect of limited shoulder movements on hand positioning. Grip strength was also reduced in many of these children. All the children with total-plexus lesions had diminished grip strength and half of them had impaired tactile sensibility. In most children with total-plexus lesions, performance of activities in daily life was affected as were bimanual activities requiring use of the involved limb. Hand preference was affected in children with a right-sided injury. From a clinical perspective, as well as for research, it is important to describe OBP injuries not only in terms of impairment but also of disability.


Asunto(s)
Traumatismos del Nacimiento/fisiopatología , Plexo Braquial/lesiones , Trastornos de la Destreza Motora/etiología , Actividades Cotidianas , Adulto , Brazo , Preescolar , Femenino , Estudios de Seguimiento , Lateralidad Funcional , Fuerza de la Mano , Humanos , Recién Nacido , Masculino , Trastornos de la Destreza Motora/fisiopatología , Evaluación de Resultado en la Atención de Salud , Rango del Movimiento Articular
20.
Exp Brain Res ; 104(2): 323-30, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7672024

RESUMEN

The adaptation of the grip forces to the frictional condition between the digits and an object relies on feedforward sensorimotor mechanisms that use tactile afferent input to intermittently update a sensorimotor memory that controls the force coordination, i.e., the ratio between grip force (normal to the grip surface) and load force (tangential to the grip surface). The present study addressed the development of these mechanisms. Eighty-nine children and 15 adults lifted an instrumented object with exchangeable grip surfaces measuring the grip and load forces. Particularly in trials with high friction (sandpaper), the youngest children used a high grip force to load force ratio. Although this large safety margin against slips indicated an immature capacity to adapt to the frictional condition, higher grip forces were produced for more slippery material (silk versus sandpaper). The safety margin decreased during the first 5 years of age, in parallel with a lower variability in the grip force and a better adaptation to the current frictional condition. The youngest children (18 months) could adapt the grip force to load force ratio to the frictional condition in a series of lifts when the same surface structure was presented in blocks of trials, but failed when the surface structure was unpredictably changed between subsequent lifts. The need for repetitive presentation suggests a poor capacity to form a sensorimotor memory representation of the friction or an immature capacity to control the employed ratio from this representation. The memory effects, reflected by the influences of the frictional condition in the previous trial, gradually increased with age. Older children required a few lifts and adults only one lift to update their force coordination to a new friction. Hence, the present finding suggests that young children use excessive grip force, a strategy to avoid frictional slips, to compensate for an immature tactile control of the precision grip.


Asunto(s)
Dedos/fisiología , Fuerza de la Mano/fisiología , Actividad Motora/fisiología , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Niño , Preescolar , Fricción , Humanos , Lactante , Sensación
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