Perinatal motor behaviour and neurological outcome in spina bifida aperta

Aim of the study: In the present longitudinal study we investigated the relationship between prenatal motor behaviour and the postnatal neurological sequelae of infants with spina bifida aperta. Methods and patients: Prenatal isolated leg movements and general movements of 13 fetuses/infants with spina bifida aperta were assessed by means of ultrasound recordings, and were compared with: 1. the spinal level of morphological defect (meningo-myelocele), 2. the postnatal motor behaviour, 3. the postnatal sensory function, and 4. the final motor outcome. Results: In all 13 cases studied, the spinal defect was either at thoracic (n = 8) or at lumbal (n = 5) level. All fetuses displayed active leg movements corresponding to the functioning of low lumbal myelum segments (L4-5 in two cases or L5-S1 in 11 cases), despite vertebral defects at high localisation. These leg movements were of normal quality (normal in appearance) and endogenously generated, since no external stimulus was exerted to elicit them. This implies that in fetuses with spina bifida aperta active leg movements can be generated at spinal segments which are located at (n = 1), or under (n = 12) the meningo-myelelocele. Postnatally, for a short period of time (mostly during the first few hours), leg movements related to myelum function at (n = 1) or lower than (n = 7) the spinal defect were detected. However, only in two infants these early leg movements were of normal quality and corresponded with the final motor outcome. In contrast to these early neonatal leg movements, early sensory function was strongly related to the spinal defect (r = 0.76; P = 0.005) and to the final motor outcome (sensory function predicted outcome in all infants of whom follow-up was performed). Conclusion: These data on fetuses/infants with spina bifida aperta strongly indicate that a discrepancy exists between the occurrence of prenatal leg movements and the spinal localisation of the meningo-myelocele on the one hand, and between the occurrence of pre-and postnatal leg movements on the other hand (quantity and quality). (C) 1997 Published by Elsevier Science Ireland Ltd.