Incomplete Spinal Cord Syndromes: Current Incidence and Quantifiable Criteria for Classification.

The demographics of acute traumatic spinal cord injury (SCI) have changed over the last few decades, with a significant increase in age at the time of injury, a higher percentage of injuries caused by falls, and incomplete tetraplegia becoming the most common type of neurological impairment. Incomplete SCI syndromes, most specifically central cord syndrome (CCS), anterior cord syndrome (ACS) and Brown-Sequard syndrome (BSS), constitute a substantial proportion of incomplete tetraplegia and SCI overall. Nevertheless, the updated incidence of these syndromes is not well known, and their estimates vary considerably, largely because of methodological inconsistencies across previous studies. A retrospective analysis of individuals with new traumatic SCI enrolled in the Spinal Cord Injury Model Systems database between January 2011 and May 2020 was performed. Using newly proposed computable definitions for ACS and BSS, as well as an existing quantitative definition of CCS, we determined the current incidence and neurological characteristics of each syndrome. Within the population of individuals with a traumatic SCI, including all levels and severity of injuries (N = 3639), CCS, ACS, and BSS accounted for 14%, 6.5%, and 2%, respectively. Of the 1649 individuals with incomplete tetraplegia in our cohort, CCS was the most common syndrome (30%), followed by ACS (10%) and BSS (3%). Using quantifiable definitions, these three syndromes now account for ∼22% and ∼44% of cases of traumatic SCI and incomplete tetraplegia, respectively, with CCS having increased over the last decade. This updated information and proposed calculable criteria for these syndromes allow for a greater understanding of the incidence and characteristics of these syndromes and enable greater study in the future.