Suspected spinal cord or cauda equina pathology is an emergency that must be dealt with swiftly, with appropriate referral and investigations. Constipation is a clinical diagnosis of exclusion, but should not be forgotten as a cause of major morbidity when severe in nature. It can mimic an acute abdomen, sepsis and even spinal cord pathology. We describe a case of cauda equina syndrome in a young man. The pathology responsible was found to be constipation with faecal impaction, once nerve and bony pathology were excluded. When treated, there was almost immediate resolution of the neurologic signs and urinary retention.