Sigmoid volvulus (SV) is the wrapping of the sigmoid colon around its mesentery, and sigmoid gangrene is a catastrophic complication of SV. Although the diagnosis of SV is generally not difficult, unfortunately, most of the clinical, laboratory and radiological signs are not pathognomonic in demonstrating sigmoid gangrene. The treatment of gangrenous SV requires emergency surgery. Sigmoid gangrene worsens the prognosis of SV by doubling the mortality rate.