As the population ages, sigmoid volvulus appears to be occurring more frequently. This entity has always been common in the Eastern European countries, accounting for 30% to 50% of all intestinal obstructions.1 Varying series in the American literature have placed the incidence of sigmoid volvulus between 1% and 8% of intestinal obstructions.2-5 There has been an increase in the number of reported case series in recent years.6,7
The exact cause of this condition is unknown, but it is predisposed by several anatomic features, the most important being a redundant sigmoid colon, either congenital or acquired. A high residue diet with a large amount of "roughage" and chronic constipa-tion may be factors contributing to the redundancy. A second feature leading to volvulus is an afferent and an efferent limb that lie close to each other while its mesocolon is both long and freely movable. This arrangement is regarded as congenital or due to inflammation of