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Key anatomic dimensions of the sigmoid colon

Sigmoid volvulus is a life-threatening condition that results from the rotation of the sigmoid colon on its mesenteric axis leading to a closed-loop obstruction. It is a common cause of intestinal obstruction; in the “volvulus belt” of Africa and the Middle East, 20-50% of all bowel obstructions are a result of volvulus, almost exclusively of the sigmoid colon. In sub-Saharan Africa, sigmoid volvulus tends to affect males more often than females (3:1 ratio), and is associated with a high mortality rate of around 20-25% depending on the series.

A gangrenous sigmoid volvulus

The goals of treating sigmoid volvulus are to minimize intervention-related morbidity and mortality and recurrence rate, however the ideal method to achieve this outcome remains unclear. Sigmoid volvulus can be classified as being either gangrenous or non-gangrenous, which is only determined definitively during surgery. Gangrene necessitates resection, while non-gangrenous sigmoid volvulus is amendable to both resective and non-resective treatment modalities.

A non-gangrenous sigmoid volvulus

UNC and KCH Departments of Surgery continue to study this common and often lethal condition that affects otherwise healthy patients. Past efforts focused on defining the epidemiologic and anatomic aspects of sigmoid volvulus. Current efforts are focused on developing best practice guidelines as well as conducting a prospective randomized trial to determine the ideal management strategy for both gangrenous and non-gangrenous sigmoid volvulus. The purpose of the proposed research is to better understand the mortality associated with various treatment strategies, namely Hartmann’s procedure, resection and primary anastomosis, and mesosigmoidopexy. This understanding will guide surgical decision-making in the care of patients with sigmoid volvulus, and be relevant to other acute surgical conditions affecting the left colon.

Classic supine (left) and upright (right) radiographs of sigmoid volvulus


JC Samuel, N Msiska, AP Muyco, BA Cairns, AG Charles (2012). An observational study addressing the anatomic basis of mesosigmoidopexy as a rational treatment of non-gangrenous sigmoid volvulus. Tropical Doctor, 41(1):44-45.

A Akinkuotu, JC Samuel, N Msiska, C Mvula, AG Charles (2011). Anatomic variation of the sigmoid colon in the pathogenesis of sigmoid volvulus in Lilongwe, Malawi. Clinical Anatomy, 24(5): 634-637.

JC Samuel, A Akinkuotu, N Msiska, BA Cairns, AP Muyco, AG Charles (2010). Re-examining treatment strategies for sigmoid volvulus: an analysis of treatment and outcomes in Lilongwe, Malawi. Global Journal of Surgery, 1(2):149-153.