Neonatal spinal cord injury after an uncomplicated caesarean section

Introduction

Spinal cord injury in a newborn is a rare condition, with an estimated incidence ranging from 1 per 29,000 to 1 per 80,000 live births [1, 2]. Typical symptoms are respiratory dysfunction, hypotonia and flaccid or spastic paralysis of the extremities, severe cases may also lead to death during labour or soon after birth. The underlying causes are often related to birth trauma, but also intrauterine conditions like hyperextension of the neck are described [3]. Whereas spinal cord lesions are frequently reported after complicated vaginal deliveries, they are rare after an uncomplicated caesarean section. We report an extremely rare case of spinal cord injury in a term infant born by uncomplicated caesarean section following cephalic presentation.

Case report

A 3460 g male infant was born at 38^+5/7 weeks’ gestation after an uneventful pregnancy. He was the second child of a young and healthy couple. Foetal ultrasounds showed regular cephalic presentation, no signs of developmental abnormalities were detected. The boy was born after an uncomplicated caesarean section. Immediately after birth the infant presented hypotonia of both upper limbs. Moro reflex, grasping or deep tendon reflexes were completely absent and there was no response to pain stimuli. The muscular development of the upper limbs including hand and finger muscles was normal. On the 2^nd day of life the infant was transferred to our unit for diagnostic workup. Neurologic findings of the upper extremities were unchanged. There were no abnormalities in cranial nerve functions. Muscle bulk, tone and movement of lower limbs were normal. Vesicorectal function was preserved. Laboratory findings including a coagulation screen were normal. Head ultrasounds were repeatedly normal. Accurate anamnesis revealed that the mother had perceived reduced foetal movements in the last days of pregnancy. An MRI of the head and spine at 48 h of life revealed a thickening of the spinal cord at C3-T1 with a hyperintense signal in T2 and a hypointense signal in T1. A restriction of diffusion reflecting a possible ischaemic lesion was noted (Figure 1). No traumatic lesions of the bone were described. Both brachial plexuses were intact. Cortisone treatment over 5 days led to no clinical improvement. At 20 days the MRI showed a normalisation of the thickening at C3-T1. At C4-C7 there was a hyperintense signal in both anterior horns.

Figure 1:

Fusiform thickening of the spinal cord with hyperintense areas in T2 and a hypointense signal in T1. The axial T2 weighted images show a marked cordon-like hyperintensity along the anterior horn of the corticospinal tract.

One month after discharge the mother reported slightly improved finger movements, which were barely clinically detectable. Neurologic examination showed a reduced tone and atrophy of deltoid, biceps and brachioradialis muscles. Reaction to nociceptive stimuli was present, resembling the presence of somatosensory and motor afferent neurons of upper limbs, which were confirmed by electroneurography. At 7 months of age the infant presented a flaccid paresis of the upper extremities with marked muscular atrophy despite physical therapy. The MRI at this age showed a persistence of focal hyperintense areas along the anterior horn of C4-C7 (Figure 2).

Figure 2:

At 7 months the thickening and the diffuse hyperintensity in T2 within the cervical spinal cord almost disappeared. There is a persistence of focal hyperintense areas along the anterior horn at level C4-C7.

Discussion

Spinal cord injury in a newborn is a rare condition, usually reported in association with difficult and precipitate deliveries, intrauterine asphyxia, forceps extraction, uterine contraction or a constriction ring [4]. Whereas spinal cord injury is often reported associated with difficult spontaneous delivery, we found only three cases reported after uncomplicated caesarean section following cephalic presentation [5–7]. In one exceptional case an astrocytoma was the cause for the spinal cord lesion [7]. In another case the authors postulate that an acute hypoxic-ischemic insult along with a deflexed head during labour may have led to the spinal cord lesion [5]. That case differs from our own in that our infant showed no signs of hypoxic-ischemic encephalopathy.

Although unique for some aspects, our case reinforces the hypothesis that an intrauterine vascular event may lead to a spinal cord lesion, in analogy to previously reported cases [6, 8]. In one case the MRI scan revealed cavitations in the proximal cord after a possible vascular event [6]. Darwish et al. reported three infants with intrauterine spinal cord lesions despite uncomplicated births. Based on the predominant cervical spinal deficit they postulated a deficit in perfusion of the anterior spinal artery in the lower cervical segments as the most likely pathogenic mechanism [8]. The clinical and radiologic findings in our case strongly support this hypothesis. To our knowledge, our case is the first where MRI findings show clear ischaemic lesions in the anterior segment of the spinal cord.

Although difficult to determine, the timing of injury is important in parental counselling and also with respect to legal issues. Based on the first MRI findings at 48 h of life the lesion occurred in the peri-partum period, which is also proven by the normal muscular development of the upper limbs on the first days of life. Unfortunately it is not possible to determine the exact timing of the injury, especially whether it occurred before birth or during labour. Anamnestic data of reduced foetal activity some days prior to delivery in the absence of other possible causes make an intrauterine ischaemic event very likely. In addition, this information is also consistent with the first MRI and the clinical findings. The cause leading to the ischaemic lesion remains unclear, as we found no evidence of vascular anomalies and a coagulation screen was normal. Treatment is still challenging and consists mostly in supportive therapy. After treatment with cortisone we evidenced a reduction of the spinal cord thickening in the control MRI. However, this may also reflect the natural course of the infant’s pathology and we did not see any clinical improvement.

In conclusion, we report an extremely rare case of spinal cord injury after an uncomplicated caesarean section following cephalic presentation. Although the precise timing of injury is difficult to evaluate, based on the clinical and MRI findings we suggest that small ischaemic spinal cord lesions may occur in uncomplicated pregnancy. In such cases spinal cord lesions may not be related to a difficult delivery. Treatment of this condition is challenging, the overall prognosis remains poor.