RESUMEN
Compression of the neural structures in spine by an intradural arachnoid cyst is a rare entity. At times such a cyst is an incidental finding. Spinal epidural injection is one of the few rare etiological factors for its development. Symptomatic cysts can present with variable neurological manifestations depending on the spinal level involved. This includes back pain, lower limb weakness, and sphincteric dysfunction. If asymptomatic, they can be followed radiologically. Surgical decompression along with a histological diagnosis is reserved for cysts that are enlarging, symptomatic or the ones for whom the diagnosis is uncertain. Incomplete excision of cyst wall or simple fenestration and decompression mandates close follow-up, clinically and radiologically for further recurrences.