Anatomy - Right Hemicolectomy, Robot-Assisted, with Complete Mesocolic Excision (CME) and UFA (Uncinatus First Approach) (Critical View Concept (CV))

The colon frames the loops of the small intestine along the inner abdominal wall and below the liver and stomach. Its position is intraperitoneal or secondary retroperitoneal. The primary function of the colon is to thicken the chyme by absorbing water. The total length of the colon averages 120–150 cm. It begins at the ileocecal valve and ends at the rectosigmoid junction, transitioning into the rectum.

The colon is divided into the following sections:

• Cecum (or Caecum) with the appendix
• Ascending colon
• Transverse colon
• Descending colon
• Sigmoid colon

The longitudinal muscle layers of the colon form three external, band-like structures known as taeniae, categorized as follows:

• Taenia mesocolica: Positioned toward the mesentery
• Taenia libera: Free on the surface, facing the abdominal wall
• Taenia omentalis: Connected to the greater omentum

Appendices epiploicae refer to fat appendages arising from the tela subserosa, located near the free taeniae.

Plicae semilunares are inward folds of all layers of the colonic wall, while haustra are the outward bulges between these folds.

Structures Relevant to Right Hemicolectomy

The following intestinal sections, in order from proximal to distal, are pertinent to a right hemicolectomy:

• Right colonic flexure and lateral right hemicolon
• Ascending colon
• Cecum with the appendix

• Definition: A blind-ending initial portion of the ascending colon, forming an outpouching; Latin: caecus = blind
• Length: 5 – 7 cm
• Synonyms: Caecum, blind gut
• Position: Intraperitoneal or secondary retroperitoneal, located below the ileocecal valve (valva Bauhini)
• Identification: Recognized by the taeniae and the vermiform appendix
• Vermiform appendix: Intraperitoneal, situated at the confluence of the taeniae on the cecal pole. Length: 6 – 20 cm, average: 8 cm. The three taeniae merge at the appendix base.

• Definition: The segment of the large intestine extending from the ileocecal valve (ileum entry) to the right colonic flexure (flexura coli dextra)
• Synonyms: Ascending colon or simply “ascending.”
• Position: Secondary retroperitoneal; extends from the lower right abdomen to the right flexure. It is fixed to the posterior abdominal wall via Toldt’s fascia.
• Length: 12 – 20 cm
• Identification: Identified by the longitudinal muscle bundles (taeniae), which retain their naming conventions from the transverse colon. The diameter is significantly larger than that of the descending colon.