Cauda Equina Syndrome: A Literature Review of Its Definition and Clinical Presentation

Objective: To review the current evidence for the signs and symptoms of cauda equina syndrome (CES). Data Sources: Relevant literature sourced through Medline, Embase, and CINAHL using the key search words "cauda equina syndrome" combined with "definition," "clinical presentation," "signs and symptoms," "pathology" and "etiology." Study Selection: Not applicable. Data Extraction: Not applicable. Data Synthesis: Three reviewers independently extracted data on CES from the literature specific to its definition, clinical presentation, and etiology. Of 111 articles, 105 were included for review, and relevant information on CES was synthesized into a framework structured as per a clinical consultation. A content analysis was then conducted using the method adopted by the Chartered Society of Physiotherapy whereby the level of consensus for each sign and symptom of CES was determined by its percentage coverage within the literature: 100% coverage equals unanimity, 75% to 99% equals consensus, 51% to 74% equals majority view, and 0% to 50% equals no consensus. This enabled the frequency of each reported sign and symptom to be ranked. Articles that included specific definitions for CES were divided into 3 categories: those that (1) included generalized statements, (2) stated a pathomechanical basis, and (3) defined the syndrome by its clinical presentation. Throughout this review, the frequencies of specific etiologies and pathologies were noted. Together with details of clinical presentation, this enabled a comprehensive review of CES. No single aspect of CES within the literature achieved unanimity or consensus; however, a majority view indicated that there would be bladder and sensory disturbance (74% and 66% of all articles, respectively). The most commonly cited pathology resulting in CES was identified as the disk (45% of all articles reviewed). Conclusions: There are marked inconsistencies in the current evidence base surrounding the etiology and clinical presentation of CES, with 17 definitions identified. Subclassifications of the definition of CES are ambiguous and should be avoided. From reviewing 105 articles, a single definition of CES is proposed. For a diagnosis of CES, one or more of the following must be present: (1) bladder and/or bowel dysfunction, (2) reduced sensation in the saddle area, and (3) sexual dysfunction, with possible neurologic deficit in the lower limb (motor/sensory loss, reflex change).