Gallbladder volvulus, or torsion of the gallbladder, is a condition in which the organ twists on its long axis to the point where its vascular supply is compromised. [1, 2, 3] First recognized in the late 19th century, this condition remains a rare entity that seldom is diagnosed preoperatively.  It is encountered most frequently in patients who are fragile and elderly. A delay in the diagnosis and treatment of gallbladder volvulus may result in life-threatening consequences. 
Torsion of the gallbladder should be treated by means of prompt cholecystectomy. Operative intervention is necessary to avoid a fatal outcome due to nonresected gallbladder volvulus.
Pathophysiology and Etiology
Torsion of the gallbladder can be complete (ie, >180º) or incomplete (ie, <180º). Complete torsion of a mobile gallbladder on its pedicle interferes with the blood supply to the organ, and if this condition is unrelieved, gangrene develops.
Two anatomic variants of the gallbladder might undergo torsion. In one type, the gallbladder has a mesentery that is prone to torsion.  In the other type, the mesentery supports only the cystic duct, allowing a completely peritonealized gallbladder to hang freely. Intermediate forms with a partial mesentery of the gallbladder and a mesentery of the cystic duct also are described.
In adults, a mesentery of the gallbladder can be acquired. The more frequent occurrence of torsion in elderly persons may be explained by the loss of fat and the atrophy of the tissues that may occur with advancing age, leaving the gallbladder hanging freely.
The precipitating factors for the final event of torsion have been cited as violent movements, including intense peristalsis of the neighboring organs; kyphoscoliosis of the spine; visceroptosis; and tortuous atherosclerotic cystic artery. The role of gallstones is debatable. Approximately 20-33% of patients with torsion have gallstones. Intense peristalsis of the stomach or the duodenum has been implicated in clockwise rotation, whereas the transverse colon is implicated in counterclockwise rotation.
Between 1898, when Wendell first described gallbladder volvulus, and the early 21st century, only about 300 cases of gallbladder torsion were reported. Since the first few years of the 21st century, however, the incidence appears to have increased, possibly because of an increase in life expectancy. As of 2014, about 500 cases had been reported.  The peak incidence of gallbladder volvulus occurs in persons aged 65-75 years; 84% of patients are elderly women.