As President of the 16th Scientific Meeting of the European Academy of Childhood Disability, I have been privileged to influence the scientific programme and place some emphasis on issues of hand function. Thus we will enjoy being addressed at the Edinburgh meeting by Professor Sheila Henderson on the topic of ‘What makes handwriting so difficult?’.

The objective of this study was to investigate the background and associated factors in a representative group of young males with Asperger syndrome (AS) presenting at a specialized autism clinic. One hundred males aged 5 years 6 months to 24 years 6 months, with a mean age of 11 years 4 months (SD 3y 10mo), who had a clinical diagnosis of AS were included in the study. An in-depth review of their medical records and neuropsychological test data was performed. There was a high rate (51%) of non-verbal learning disability (defined as Verbal IQ more than 15 points higher than Performance IQ), but otherwise there was little or no support for the notion of right-hemisphere brain dysfunction being at the core of the syndrome. There was a very high rate of close relatives with autism spectrum problems, but also high rates of prenatal and perinatal problems, including prematurity and postmaturity. In comparison with general population data, those with AS very often had a combination of genetic and prenatal and perinatal risk factors. Non-verbal learning disability test results applied in about half the group. There was a subgroup of individuals with AS who had macrocephalus. However, there was no support for an association of AS with low body mass index.

This study explored the relation between a motor-free visual perceptual deficit, different visual–motor integration deficits, and different motor skills in children with developmental coordination disorder (DCD). Thirty-six children (22 males), aged 9 or 10 years, with DCD and a control group (n=36), matched for age and sex, were assessed with the Movement Assessment Battery for Children (MABC), a ball-catching test, a jumping test, a timed response task to a visual moving stimulus, and the Beery-Buktenica Developmental Test of Visual–Motor Integration, incorporating copying, visual discrimination, and tracing tasks. Children with DCD performed significantly worse than the control group on all measures. The visual discrimination task did not correlate significantly with any of the motor tasks. The visual timing task correlated significantly with the ball-catching test in the DCD group. The copying test was significantly correlated with the MABC in the DCD group. The association between visual–perceptual deficits and motor tasks was shown to be task specific.

We assessed the architecture of the medial gastrocnemius in nine children (five males, four females; age range 6 to 15 years; mean 10 years 10 months, SD 3 years 6 months) with spastic diplegia by ultrasound imaging before and after a gastrocnemius recession. The children were ambulant (seven independent, one with a posterior walker, one using crutches) before and after surgical intervention. We compared values for fascicle lengths and deep fascicular-aponeurosis angles with those from a group of normally developing children (five males, five females; age range 6 to 11 years; mean 8 years 4 months, SD 1 year 4 months). Despite a variable interval between assessments (from 56 to 610 days), fascicles were shorter (p=0.00226) and the deep fascicular-aponeurosis angle increased (p=0.0152) after intervention. Fascicle lengths of patients were similar to those in the group of normally developing children before surgery. After surgery, fascicles in the group of children with spastic diplegia were shorter than in their normally developing peers (p=0.00109). The gastrocnemius recession procedure alters muscle architecture, though the degree of fascicular shortening varied, with four of the participants in our study losing less than 10% of their original fascicular length at maximum dorsiflexion. Increases in ankle-joint power in walking, observed after surgical intervention in children with spastic diplegia, may be due to a more normal ankle position rather than to improvements in the active mechanical performance of the gastrocnemius.

We assessed the influence of digitigrade gait pattern, topographical types, severity of motor involvement, and locomotor experience on the body's centre of mass (COM) displacement during gait in children with spastic cerebral palsy (CP). Three-dimensional COM displacements were computed from ground reaction forces in 51 independent digitigrade walkers (29 males, 22 females; mean age 10 years 6 months, SD 2 years 7 months, range 7 to 15 years). Results obtained from 10 participants without disabilities (five males, five females), in the same age range as the patients with CP, were used as a reference plantigrade group. Vertical and forward COM displacements were significantly different between the digitigrade and the plantigrade walkers. Neither the topographical type (quadriplegia, n=5; diplegia, n=20; right hemiplegia, n=13; left hemiplegia, n=13), nor the severity of motor involvement, nor the locomotor experience influenced COM displacements. We conclude that the COM displacement during gait in patients with CP was mainly influenced by the digitigrade gait pattern encountered in this neurological disorder rather than the different topographical types and motor involvements.

This study examined spatial and temporal organization of muscle activity in response to seated forward platform perturbations in typically developing (TD) infants and in infants at risk for ongoing neuromotor delays. Twelve high-risk (HR) infants (six males, six females) and 12 TD infants (nine males, three females) aged 8 to 10 months (corrected for prematurity), who were all independent sitters, participated in this study. Surface electromyograms recorded muscle responses to forward perturbation in the neck, trunk, and leg (6cm amplitude, 12cm/s). Center of pressure measures were also recorded. The TD infants demonstrated significantly more phasic responses than the HR infants, who had more trials with tonic activity and more trials with no burst of muscle activity (Mann–Whitney U test, two-tailed, p=0.006). The TD infants demonstrated caudalcephalo, directionally appropriate recruitment patterns more often than the HR infants. There were some similarities between the two groups, with no significant difference between any of the center of pressure measures or onset latencies. Results suggest that postural development in HR infants with motor delays is complex. Some elements of seated postural control appear to be developmentally appropriate, e.g. presence of phasic activity in directionally appropriate muscles sequenced in a caudalcephalo pattern. However, frequency of these age appropriate responses was significantly lower in HR infants, who demonstrated many normal, albeit immature, responses, such as cephalocaudally sequenced muscle activity.

The aim of this study was to evaluate anaerobic muscle performance in children after long-term recovery from Guillain-Barré syndrome (GBS). Participants were recruited from all children and adolescents with GBS admitted to The Hospital for Sick Children, University of Toronto, Canada, between 1988 and 1995. We assessed 17 children (nine males, eight females; mean age at GBS diagnosis 7 years 11 months, SD 4 years 2 months; mean age at testing 14 years 1 month) more than two years after acute GBS. Participants completed the Wingate anaerobic test to evaluate mean and peak muscle power. For mean arm muscle power (mean 47.5% [SD 17.4%] of normal), only two participants were in the normal range. For mean leg muscle power (mean 83% [SD 28.3%] of normal), 15 participants were in the normal range. For arm peak power (mean 92.6% [SD 20.7%] of normal), 12 participants were in the normal range. For leg peak power (mean 116.3% of normal, SD 15.8%), all participants were in the normal range. Detailed manual muscle testing with the modified Medical Research Council scale was done on 34 muscle groups. Data were pooled to give a mean arm and leg muscle strength score (9.7, SD 0.30 and 9.4, SD 0.50 respectively). Pearson's correlations of muscle endurance with arm and leg strength were not significant. Children with GBS have excellent long-term recovery of peak muscle power. Muscle endurance, measured by mean muscle power, was normal in the legs but markedly low in the arms. Pediatric rehabilitation programs after GBS should specifically target endurance of arm muscles.

Twenty-nine patients (16 males, 13 females) with Joubert syndrome were identified from ophthalmology, neurology, and genetic databases covering a 15-year period at Great Ormond Street Hospital, London. Criteria for diagnosis included absent or markedly hypoplastic cerebellar vermis, abnormal eye movements, and developmental delay. Five patients had died. Scans and notes were available for 22 patients, and 18 cases were clinically reviewed. The median age was 10 years 10 months (range 3mo to 19y) and the median follow-up was 8 years 5 months (range 3mo to 19y, with one new patient seen at 3mo of age). Cerebellar vermis hypoplasia/aplasia with ‘molar tooth sign’ in the axial plane was present in 22 of 22 patients, coloboma in 6 of 22, and polydactyly in 6 of 22. In the 18 clinically reviewed, apnoea occurred in 13 patients. Five had renal problems with cysts and 4 of 5 had abnormal electroretinograms (ERGs). Visual electrophysiology was abnormal in 14 of 18 patients, and in 6 there was evidence of deterioration in the ERG. Blood investigations of organic acids, phytanic acid, very-long-chain fatty acid, and transferrin were normal in 12 patients tested. Developmental assessment showed that 6 of 15 patients aged more than 5 years were at mainstream school, and 12 of 18 had started walking between 22 months and 10 years. Speech difficulties and behavioural problems were prominent.

To delineate quantitatively differences in suck–swallow–respiration coordination during feeding in term infants exposed to drugs in utero, 16 control infants (10 females, six males; mean birthweight 3209g, standard error of the mean [SEM] 103g) and 15 drug-exposed infants (seven females, eight males; seven cocaine, eight opiates; neonatal abstinence [Finnegan] scores less than 10; mean birthweight 3001g, SEM 93g) were studied in the first three days of life and again at one month of age. Coefficients of variation (COVs) of suck–suck, swallow–swallow, and breath–breath intervals were used as measures of stability of individual rhythms. COVs of suck–swallow and swallow–breath intervals were used to determine stability of multiply integrated rhythms. In the first three days of life, a significantly higher percentage of ‘apneic swallows’ (runs of three or more swallows not associated with breathing movements, divided by total run-swallows) was noted during feeding in the drug-exposed infants (mean 5.3% SEM 1.7%) compared with controls (mean 0.9%, SEM 0.4%; p<0.02), who also had less breath–breath rhythmic stability (higher COV) and shorter swallow–breath intervals. These differences were no longer evident at one month of age. Opiate-exposed infants were generally more affected than the cocaine-exposed infants. Swallowing was less rhythmic in the drug-exposed cohort, especially in opiate-exposed infants, but this difference also disappeared by one month. In the first days of life, drug-exposed infants were less efficient feeders, ingesting less volume per run-swallow than controls (mean 0.31ml, SEM 0.05ml, versus 0.45ml, SEM 0.05ml; p<0.05). The decreased efficiency appeared to be compensated for by a slightly faster swallow rate (mean 53 swallows per minute SEM 2 versus 47 swallows per min, SEM 1, in controls; p<0.005). By one month of age these differences between groups had disappeared as well. Intrauterine drug exposure, even in infants with relatively mild symptoms of withdrawal, may adversely impact development of brainstem respiratory and swallow centers, thus affecting, albeit transiently, the underlying biorhythms of feeding.

A preliminary cross-sectional study of 72 Hong Kong Chinese infants suggested that these infants learn to roll from supine-to-prone before rolling from prone-to-supine i.e. the opposite to teaching in most western texts. Three-hundred and sixty mothers were recruited postpartum and asked to record, on a chart, information related to the developmental milestone of rolling over for their infants (49% male) during the next 9 months. Telephone reminders were given at 4 and 8 months and, by the end of the study, information had been obtained from 240 mothers (67% of original sample, 51% male infants). Mean ages of rolling over were 5.1 months (SD1.5) for supine-to-prone and 5.7 months (SD1.3) for prone-to-supine. Age of rolling over from supine-to-prone was not influenced by usual sleep position, infant's sex, mother's intention to breastfeed infant, number of siblings, marital status, main daytime caregiver, or feeding method over 9 months. Hong Kong Chinese infants roll from supine-to-prone before they roll from prone-to-supine.

Two individuals with pyruvate dehydrogenase (PDH) deficiency due to missense mutations in the gene for the E1α subunit (PDHA1) presented during childhood with dystonia. The first patient, a male, presented at age 4 years with dystonia affecting the lower limbs, which responded to treatment with combined carbidopa and levodopa. The second patient, a female, was first investigated at age 6 years because of a dystonic gait disorder. In both patients, the main clue to the biochemical diagnosis was a raised concentration of lactate in the cerebrospinal fluid. PDH activity was significantly reduced in cultured fibroblasts in both cases. Dystonia is a previously unrecognized major manifestation of PDH deficiency and is of particular interest as the mutations in the PDHA1 gene in these patients have both been identified previously in individuals with typical presentations of the condition.

Cerebral paradoxical embolism has not until now been described as a cause of cryptogenic stroke in newborn infants. A male infant was born at 27 weeks 2 days' gestational age by emergency Caesarean section in a twin pregnancy because of intrauterine growth retardation and absence of diastolic flow in the twin. His birthweight was 950g (50th centile). Apgar scores were 7 and 8 at 1 and 5 minutes respectively. At 17 days of life he showed sudden respiratory distress and signs of encephalopathy. Presence of deep venous thrombosis, patent foramen ovale (PFO), and clinical progression suggested paradoxical embolism which were confirmed by neuroradiological findings. The high incidence of PFO and central venous catheter-related deep venous thrombosis in newborn infants suggest that paradoxical embolism is probably a more common complication than has been thought.

Giant axonal neuropathy (GAN) is a chronic progressive disease of the peripheral nervous system, but lesions can also occur in the central nervous system (CNS), especially in the brainstem and cerebellum. Its mode of inheritance is autosomal recessive, with parents of affected children often being consanguineous, but sporadic cases have been reported.