Abstract
A case of adult malrotation (right paraduodenal hernia) associated with intestinal necrosis is reported. A 32-year-old woman with progressive epigastralgia and vomiting was diagnosed as having diffuse peritonitis. An emergency operation was performed. The operative finding was right paraduodenal hernia associated with massive intestinal necrosis. In Japan, only 16 patients who underwent surgery due to malrotation have been reported, but paraduodenal hernia has not been reported.