A systematic review of the presentation of scan-negative suspected cauda equina syndrome

A significant proportion of patients presenting with suspected cauda equina syndrome (CES) do not have associated radiological evidence to support the diagnosis, often termed ‘scan-negative’. Due to the limited number of studies regarding the matter, there is no clear understanding for this presentation. As a result, no treatment protocol exists for the scan-negative group. The purpose of this review is to assess the potential contributing factors leading to the presentation of suspected CES with normal imaging. A systematic review was conducted on PubMed and Cochrane databases. Bibliographies of key articles and Google Scholar were searched for additional results. The search strategy provided 204 results. Of those, 8 had no identifiable causation for suspected CES and were included for systematic review. 6 of 8 studies investigated for a difference in clinical presentation between cohorts that may indicate a normal scan. Studies were either inconclusive and contradictory. Two studies suggest a functional somatic disorder as reasoning for negative MRI, with positive provisional findings. A psychogenic hypothesis is plausible and warrants further investigation. The need for additional studies is essential to scheming a potential treatment protocol for the scan-negative population, which currently does not exist. •Cauda Equina Syndrome (CES) is an acknowledged medical emergency.•A notable percentage of patients with clinically suspected CES have normal radiological imaging.•No treatment protocol currently exists for such a population.•There are no defining clinical characteristics that aid in distinguishing a scan-negative cohort.•A psychogenic hypothesis for a CES with negative imaging cohort has been postulated, with positive preliminary findings.