A detailed study was made of the pathology of specimens removed by hemispherectomy for the treatment of intractable epilepsy in children with unilateral middle cerebral artery stroke. Neuropathological criteria were used to differentiate strokes that occurred in early intrauterine development (before 28 weeks gestational age) from those occurring in the last trimester, at birth, or after birth: 19 children had early strokes and 21 late. There was no difference in seizure history or occurrence of febrile convulsions in these two groups. Hippocampal tissue was available in 20 patients; pathology in the hippocampus, remote from the infarcted area, showed a marked difference between early-onset and late-onset groups. Hippocampal sclerosis was uncommon in children with early-onset strokes but developed in most of the children whose strokes were of later origin. However, hippocampal sclerosis was more closely related to a clinical history of a late initial precipitating insult irrespective of infarct timing. These findings demonstrate the changing vulnerability of the developing brain and show that hippocampal pathology is more closely related to the timing of an insult than seizure history or the occurrence of febrile convulsions.

Visual masking assesses visual perception and attention; it occurs when a visual stimulus (mask) interferes with the perception of a stimulus that the participant is trying to identify (target). A backward masking study (target presented before mask) was performed on 662 children without disabilities (338 females), aged between 6 and 17 years, in order to evaluate if performance varies with age. In the masking procedure 10 letters were presented through a tachistoscope as target stimuli. Fragments of letters oriented at random (‘noise’) represented the mask. A slight improvement of visual performance from the beginning of school age to 9–12 years of age was found. This paper gives normative data for the most important parameters which can be used as a standardized reference for the procedure employed. We also studied 113 children with epilepsy (56 females), aged between 5 and 19 years, who attended a mainstream school and had been seizure free for at least 2 years. Children were tested just before starting antiepileptic drug withdrawal and re-tested 1 year later; they were drug free for 3 months before the second test. These children showed, during and after treatment, only slightly worse results when compared with healthy children of the same age; after therapy withdrawal, their visual performance slightly improved but this was not statistically significant.

The aim of the study was to examine whether school performance was reduced in children with very-low birthweight beyond what could be explained by the deficit in intelligence-score at 4 years of age. Participants (n=333) examined at 4 years of age included three subgroups on the basis of birthweight: very-low birthweight (VLBW <1501g; n=102), low birthweight (LBW 1500–2300g; n=139), and normal birthweight (NBW [ges ]2500g; n=92). The general cognitive index index (CGI) from the McCarthy Scales of Children's Abilities was used as an intelligence measurement at this assessment. At 18 to 20 years of age a telephone interview concerning school performance was conducted. Two hundred and fifty-seven participants (53% male, 47% female) entered the analysis. A model with School Performance score after the last year of compulsory school as the outcome variable, and McCarthy GCI and birthweight group as predicting variables, was used in linear regression analyses. Twenty-four per cent of the variance was explained. Birthweight had no influence in this model. In conclusion, the study did not find that birthweight influenced school performance beyond that represented by the McCarthy GCI found at age 4 years.

The objective of the American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) evidence reports is to provide the biomedical research and clinical practice communities with the current state of evidence about various interventions for the management of developmental disabilities. The AACPDM evidence reports aggregate all that has been published in the English language about outcomes of an intervention for a medical condition, gauge the credibility (i.e. strength of the internal validity) of that evidence, and identify gaps in our scientific knowledge. Methodology for developing and procedures for approving these systematic reviews can be found on the internet at www.aacpdm.org/home.html in the AACPDM Database of Evidence Reports, which contains initial and updated reports.

‘Cerebral palsy (CP) describes a group of disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain. The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, cognition, communication, perception, and/or behaviour, and/or by a seizure disorder.’

Children with congenital oro-motor disorders (COMD) are not numerous. However, as a group, they merit special consideration as management of diseases leading to COMD is complex, owing to their protracted and varying course, the diverse areas of health care involved, and the significant amount of resources their treatment requires.

Little is known about the developmental course of striking action. This cross-sectional study explored the refinement of striking in 28 children aged between 4 and 12 years and investigated how well they could use kinaesthesis to gauge the length of an unseen bat. The kinematic data (including smoothness of movement) showed quantitative differences between the age groups. In contrast, no differences were found in the children's ability to judge the length of the unseen bat: within three strikes all of the children had made a clean hit, indicating that they had successfully judged bat length. The children then appeared to memorize the bat with which they had accurately hit the target and made: (1) minimal errors when using this bat in later trials and (2) predictable errors when using two other bats of different sizes. The results show that the striking action becomes optimized over childhood, with smoothness of movement providing an index of this refinement. The findings also suggest that young children have a higher level of kinaesthetic sensitivity than has been assumed previously on the basis of static limb positioning tasks. The results suggest that the striking task used in this study might be a useful tool for investigating the development of movement skills in children with developmental disorders.

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Foreword 2

Session A: Botox - Non-Surgical 3

Session B: Upper Extremity 6

Session C: Adult Cerebral Palsy 9

Session D: Orthopaedic Aspects of Myelomeningocele 12

Session E: Intrathecal Baclofen Therapy 16

Session F: Surgery 19

Session G: General Pediatrics 22

Session H: General Pediatrics and Scales 25

Session I: Selective Dorsal Rhizotomy 28

Scientific Posters 32

Audio-Visual Program 44

Index 48

The traditional model of motor weakness derived from the works of Hughlings Jackson is that of a negative phenomenon following a cortical injury such as stroke, in contrast to the positive phenomena of brisk reflexes and the release of primitive, complex reflexes. The physiology of orderly motor neuron recruitment and de-recruitment elaborated by Henneman, in which the smallest, weakest, and slowest motor neurons are recruited first followed by increasingly large, powerful, and fast motor neurons, provided a physiological explanation for weakness following a cortical insult. This was especially so with the later work of Evarts who demonstrated that the frequency of firing of Betz cells (upper motor neurons) in the cerebral cortex specified the strength of isometric contractions. Maintaining a contraction is underpinned by pools of upper and lower motor neurons being recruited in rotation by relay as it were. Reduced populations and sizes of such upper motor neurons would result in poorly sustained firing of neurons and hence weakness. However, in cerebral palsy (CP), the injury is seldom a focal lesion in the motor cortex but more usually bilateral lesions affecting subcortical white matter. Moreover, the brains of children with CP are immature and still developing. The work of Sutherland demonstrating persistence of the wrap-around electromyogram discharges throughout the gait cycle, and subsequently of Leonard, support a model of ‘developmental co-contraction’ as the default muscle activation pattern out of which, in the uninjured state, refined, selective motor strategies emerge to provide fluency and elegance of movement. As Leonard and colleagues demonstrated, children with CP never shake off this co-contracting pattern which results in clumsy, poorly executed, and energy-intensive movements. According to the landmark study by Tedroff et al. (p 789) children who have a hemiplegia or diplegia frequently select the wrong muscles when attempting to perform a maximum voluntary contraction. This miss-selection often involves an antagonist or remote muscle from the intended joint of action. A consequence of these findings necessitates a revision of the essence of the motor disorders traditionally referred to as ‘spastic’.

Identical female twins (age 11 years) with congenital ocular motor apraxia and generalized idiopathic epilepsy are reported. Their presenting symptoms were a long history of abnormal head and eye movements. One twin developed partial sensory seizures. The patients underwent 16-channel EEG, electro-oculographic recordings, MRI of the brain, and genetic and metabolic investigations. EEG findings were consistent with idiopathic generalized epilepsy. Electro-oculographic recordings of the saccades confirmed an inability to elicit horizontal saccades without preceding head movement; saccades to the left were better than saccades to the right. MR scans for one twin showed normal findings, however, for the twin who had meningitis they revealed asymmetry between the right and left temporal lobes but no specific abnormality. DNA analysis using a series of autosomal polymorphic markers confirmed the monozygocity of the twins. White blood cell enzyme analysis excluded Sandhoff disease, Tay–Sachs disease, GM1 gangliosidosis, metacromatic leucodystrophy, Gaucher disease, Niemann-Pick disease (A and B), and Krabbe leucodystrophy. Albumin and immunoglobulin (IgA, IgG, and IgM) levels were normal. It is concluded that autosomal recessive inheritance seems the most likely explanation here, as recent studies have found insertion and missense mutations of the aprataxin gene which have been related to an early onset form of ataxia with ocular motor apraxia and hypoalbuminaemia.

The mitochondrial transfer ribonucleic acid for leucine is encoded by nucleotides 3230-3304. A-to-G transition at nucleotide 3243 can cause maternally transmitted diabetes mellitus–deafness syndrome, and MELAS syndrome. MELAS syndrome is a rare disorder of mitochondrial energy production, and is an acronym for myopathy, encephalopathy, lactic acidosis, and stroke-like episodes. Cortical malformations are heterogeneous and result from abnormal cell proliferation/apoptosis, migration, and/or differentiation of neuroepithelial cells. They are an important and relatively common cause of intractable epilepsy and neurodevelopmental disorders. The association between these A3243G mutations and cortical malformation has never before been reported. Here a 14-year-old female with A3243G mutation and polymicrogyria is described and possible aetiologies of this association are discussed.

The ‘Uptimer’ is a custom-made lightweight battery-operated remote activity monitor that records the amount of time an individual spends in the upright position, which is also known as ‘uptime’. The aims of this study were to determine levels of uptime over 24 hours and the relation between uptime and a child's age, sex, height, weight, and body mass index (BMI). Uptime was recorded in 529 normally developing children (318 females, 211 males), aged between 8 and 15 years. All children wore an Uptimer continuously for a 24-hour period that included a typical school day. Mean uptime for children in this study was 5.4 hours (SD 1.3; range 1.5 to 10.3 hours), over a 24-hour period. Uptime followed approximately a normal distribution in this population and did not have a linear relation to age, height, weight, nor BMI. Results of this study may be used as a normative database for the evaluation of uptime in children with physical disabilities.

The purpose of this study was to determine the effectiveness of muscle-release surgery for children with cerebral palsy (CP) using longitudinal and stratified analysis. Twenty-five children with CP (15 females, 10 males; age range 4 to 16 years; mean age 8 years 2 months, SD 3 years 2 months) were selected from five treatment centres in Japan. Twenty-two children had spastic diplegia, two had spastic quadriplegia, and one had athetospastic quadriplegia. Motor function for each child was assessed using the Gross Motor Function Measure (GMFM). Assessment was conducted on eight separate occasions: 1 month and 1 week before surgery, and 1, 2, 4, 6, 9, and 12 months after surgery. Participants' motor function before surgery was classified using the Gross Motor Function Classification System (GMFCS). Six children were classified at level I, three at level II, six at level III, and 10 at level IV. A significant difference was found after surgery in the GMFCS levels III and IV groups (p<0.05). Improvement in GMFM scores between 1 week before surgery and 12 months after surgery were 1, 5, 8.5, and 8.5 for GMFCS levels I to IV respectively. Results indicate that this treatment is advantageous for improving motor function in children within GMFCS levels III and IV.