Predictive value of spinal bone anomalies for spinal cord abnormalities in patients with anorectal malformations.

Aim: To evaluate the correlation between sacral/vertebral anomalies and spinal cord anomalies (SCA) on MRI, in patients with anorectal malformation (ARM).

Methods: Patients with ARM consecutively treated between January 1999 and August 2019 were included. Radiological imaging of sacrum and spine were retrospectively analyzed and correlated to the presence of SCA at MRI. Fisher's exact test and X test were used as appropriate; p<0.05 was considered statistically significant.

Results: 348 patients with ARM were enrolled in the study, 147 presented SCA at MRI. 144 patients showed spinal bone anomalies, isolated vertebral and sacral anomalies were found in 17,6% and 35% respectively. Higher level of ARM was associated with a significant higher prevalence of sacral and vertebral anomalies. A significant correlation was found between the "level" of ARM and the presence of SCA (p<0.05). Sacral anomalies were significantly correlated with the presence of SCA at MRI (p<0.05). SCA were found in 70% of patients with vertebral anomalies (VA) and in 76% of patients with sacral anomalies. The presence of multiple malformations (vertebral and sacral anomalies) are strictly related to the presence of SCA. However, the absence of spinal bone anomalies does not exclude the presence of SCA. SD was the most represented type of SCA (n=94/147), of those 96% had fatty filum. Neurological or neurourological symptoms were detected in 11,5% patients (n=17) with SCA and required neurosurgical intervention.

Conclusions: Our data confirm the strong relation between sacral or vertebral anomalies and SCA. However, in our series also patients without sacral/vertebral anomalies had SCA at MRI. Our results suggest that, despite the presence or absence of spinal anomalies, spinal cord MRI should be performed in all children with ARM, to allow a correct multidisciplinary follow-up and treatment. In fact, most patients with spinal bone and SCA are asymptomatic, but could develop clinical manifestations during their growth.