The spinal cord in neurologically stable spina bifida: a clinical and MRI study

Cerebellar motor function in spina bifida meningomyelocele

Spina bifida meningomyelocele (SBM), a congenital neurodevelopmental disorder, involves dysmorphology of the cerebellum, and its most obvious manifestations are motor deficits. This paper reviews cerebellar neuropathology and motor function across several motor systems well studied in SBM in relation to current models of cerebellar motor and timing function. Children and adults with SBM have widespread motor deficits in trunk, upper limbs, eyes, and speech articulators that are broadly congruent with those observed in adults with cerebellar lesions. The structure and function of the cerebellum are correlated with a range of motor functions. While motor learning is generally preserved in SBM, those motor functions requiring predictive signals and precise calibration of the temporal features of movement are impaired, resulting in deficits in smooth movement coordination as well as in the classical cerebellar triad of dysmetria, ataxia, and dysarthria. That motor function in individuals with SBM is disordered in a manner phenotypically similar to that in adult cerebellar lesions, and appears to involve similar deficits in predictive cerebellar motor control, suggests that age-based cerebellar motor plasticity is limited in individuals with this neurodevelopmental disorder.

Meningomyelocele: management in utero and post natum

We report a four year follow-up of 39 of 47 infants born after pre-labour Caesarean section and 68 of 79 born vaginally. Loss of motor function due to late complications was more frequent in the Caesarean section group (Fisher's Exact; P = 0.004). However, the means of the differences between the X-ray levels (measured as the last intact vertebral arch seen on standard anteroposterior roentgenograms of the spinal column) subtracted from the motor levels still favour Caesarean section (mean = 3.24; SD = 2.7) over vaginal delivery (mean = 1.2; SD = 2.7) (Student's t-test; P = 0.0003). The frequencies of other complications, death and neonatal meningitis, were not significantly different. Another 38 infants born by Caesarean section after labour were more paralysed (mean of X-ray and motor difference = 1.8, SD = 2.2) following rupture of amniotic membranes than those with intact amniotic membranes with or without labour (mean = 3.4; SD = 2.2) (Student's t-test; P = 0.0067). The differences between X-ray and motor levels for patients born by Caesarean section with intact amniotic membranes and without labour (mean = 3.6; SD = 2.4) were not significantly different from those with labour and intact amniotic membranes (mean = 2.89; SD = 1.5). The number of new cases of meningomyelocele presenting to our clinic has decreased from an average of 30 per year between 1970 and 1987 to 14 between 1988 and 1992.

Bladder dysfunction and neurological disability at presentation in closed spina bifida

Congenital closed spinal anomalies are associated with distortion of the spinal cord, the spinal nerve roots or both, and can result in neurological abnormalities of the lower limbs and neuropathic bladder dysfunction. This study reports clinical and videourodynamic findings in a group of 51 patients with closed spina bifida. The mean age at presentation to a specialist neurological clinic was 3.3 years. Twenty five patients presented with urinary tract disturbance and 12 presented with neurological problems. Thirty three had normal neurological examination or only minor objective signs, 21 had normal renal tract ultrasonography but only two patients had normal videourodynamics, with 31 having two or more abnormalities during this assessment. Neither clinical neurological assessment nor the history of voiding behaviour are reliable indicators of bladder dysfunction and subsequent risk of renal damage. Therefore, all patients with a known or suspected diagnosis of closed spina bifida should have videourodynamic assessment.