Non-traumatic Etiologies
Other SCI etiologies consist of non-traumatic causes, including congenital or genetic (e.g., spinal Bifida), degenerative, tumor (both benign and malignant), vascular (e.g., ischemia, hemorrhagic, malformations), and infectious (e.g., bacterial, viral) etiologies. Of the non-traumatic causes, congenital anomalies, or structural or functional abnormalities that occur to the fetus (also known as birth defects) (World Health Organization 2021), are most frequent in children under 4 years of age (Lee et al. 2009). Tumors are the most commonly explored non-traumatic cause of SCI in the pediatric population. Metastatic spinal cord compression (MSCC) is caused by the breakdown or compression of vertebral bodies containing the metastatic disease. In some rare cases, MSCC can be caused by a tumor growing directly into the vertebral column (National Collaborating Centre for Cancer 2008). The leading cause of MSCC in children is extra-medullary tumors, in particular neuroblastoma, followed by Ewing sarcomas, as well as other sarcomas and lymphomas (De Martino et al. 2019; Lewis et al. 1986). In individuals under 18 years of age, systemic cancer can lead to spinal cord disease. Patients with spinal cord disease could also face metastatic spinal cord compression, treatment-related transverse myelopathies, or anterior spinal artery stroke (Lewis et al. 1986). While congenital issues are a common cause of SCI in younger children, tumors become a more dominant cause as age increases. Furthermore, thoracic cord level of injury is most frequent in these cases (Lee et al. 2009).
Another common non-traumatic SCI etiology is viruses, with acute flaccid myelitis (AFM) being the primary source of insult (Galvin et al. 2013; Smith et al. 2017). AFM is triggered by certain infections—predominantly viral—that attack and cause damage to the spinal cord. These viruses, known as enteroviruses, are common infections that everyone acquires over time, but only result in spinal cord damage in a very small proportion of the population (University of Minnesota Masonic Children’s Hospital 2018). Acute flaccid myelitis presents with asymmetrical limb weakness and spinal cord MRI primarily shows grey matter involvement (Sarmast et al. 2019). AFM tends to affect older children and is slightly more prevalent in males than in females (Messacar et al., 2016). When it comes to AFM, there are no reported ethnic and racial predispositions or links to vaccination status. Additionally, affected patients are predominantly healthy, with asthma being the most common underlying illness. In some cases, patients with AFM are immunocompromised, battling organ transplants, chronic lymphocytic leukemia, immune deficiency syndrome, diabetes mellitus, and lupus—among others (Messacar et al. 2016).
As mentioned previously, in some instances, vascular complications can cause SCI. A few cases of SCI are thought to have arisen from a spontaneous spinal epidural hematoma (SSEH) (Lo 2010). Spinal epidural hematomas are very rare—accounting for less than 1% of all spinal canal space-occupying lesions. Spontaneous spinal epidural hematomas refer to blood within the epidural space without known traumatic or iatrogenic cause and have an estimated incidence of 0.1 in 100,000 per year (Figueroa & DeVine 2017). In certain cases, cavernous vascular malformations (clusters of irregularly small blood vessels and larger, stretched-out, thin-walled blood vessels filled with blood, located in the brain or spine) were the origin of SSEH (Figueroa & DeVine 2017). Like SSEH, the cavernous vascular malformation is not commonly seen in pediatric patients (Lo 2010). Although a diagnosis of non-traumatic SCI can be daunting, little can be done to prevent such an occurrence. It is essential for children of all ages to enjoy their youth and live life to the fullest, as there truly is no predictor (outside of congenital instances) that any one child will experience non-traumatic SCI.
