Most Common Location of Meckel's Diverticulum
Meckel's diverticulum is most commonly located on the antimesenteric border of the distal ileum, approximately 45-60 cm (approximately 2 feet) proximal to the ileocecal valve. 1, 2, 3
Anatomical Location Details
The precise location shows some variability in the literature:
- Distance from ileocecal valve: Ranges from 7 to 200 cm proximal to the ileocecal valve, with a mean distance of 52.4 cm 4
- Classic teaching: The "rule of two" describes it as being located 2 feet (approximately 60 cm) from the ileocecal valve 3, 5
- Typical range: Most commonly found in the last 90 cm of the terminal ileum 6
Structural Characteristics
Meckel's diverticulum is consistently identified as a saccular, blind-ending structure located on the antimesenteric border of the distal ileum. 1 This antimesenteric location is a defining anatomical feature that distinguishes it from other diverticula.
Size Parameters
- Length: Ranges from 0.4 to 11.0 cm, with a mean of 3.05 cm (approximately 2 inches per the "rule of two") 4
- Diameter: Ranges from 0.3 to 7.0 cm, with a mean of 1.58 cm 4
Important Clinical Caveat
While the antimesenteric location is standard, rare mesenteric variants have been reported 6, which can complicate diagnosis and surgical planning. This atypical presentation underscores the need for thorough intraoperative exploration when Meckel's diverticulum is suspected but not immediately visualized in its expected location.
Embryological Basis
The location is determined by embryology: Meckel's diverticulum results from incomplete obliteration of the omphalomesenteric (vitelline) duct during the 7th week of gestation 2, 3, 5, which explains its consistent antimesenteric position along the ileum.