Association of Tarlov cyst with cauda equina syndrome and spinal cord infarction following caudal epidural block: A case report

Rationale:Caudal epidural block (CEB), which injects drugs into the epidural space through a sacral hiatus, is considered a safer alternative to other approaches. Serious complications, such as cauda equina syndrome or spinal cord infarction, have been reported very rarely, but their coexistence after CEB, which may be related to the ruptured perineural cyst, also known as a Tarlov cyst, was not reported.Patient concerns:A 40-year-old male patient presented with bilateral lower extremity radicular pain. CEB was performed without image guidance. The patient exhibited sensory deficits below L2, no motor function (0-grade), hypotonic deep tendon reflexes, and no pathological reflexes.Diagnoses:Spinal cord infarction, cauda equina syndrome, and sacral level perineural cyst with hemorrhage.Intervention:High doses of steroids and rehabilitation were performed.Outcomes:The patient was discharged after 28 days with persistent bilateral leg paralysis and sensory deficits below the L2 level. The patient demonstrated no neurological improvement.Lessons:Magnetic resonance imaging, including the sacral area, should be performed before performing CEB, to confirm the presence of a perineural cyst.