sigmoid colon
The sigmoid colon is the continuation of the descending colon.
Gross anatomy
After the distal descending colon has curved medially it enters the pelvis, where it gains a mesentery and is then called the sigmoid colon. It measures approximately 15 cm in length.
It has a "S" (Greek letter sigma) shape and has a variable length and course - its apex may be as high as the umbilicus. It lies on its own mesentery - the inverted V-shaped sigmoid mesocolon.
The sigmoid colon continues as the rectum when it loses its mesentery, at approximately S3.
Relations
- anteriorly
- superiorly: loops of small intestine
- posteriorly: left internal iliac artery and vein, left ureter, piriformis muscle, sacrum, sacral plexus
- laterally
- male: pelvic side wall, ductus deferens
- female: pelvic side wall, ovary
Blood supply
- arterial: two-to-four sigmoid arteries (branch of inferior mesenteric artery)
- venous: similarly named veins drain into the inferior mesenteric vein
Nerve supply
- sympathetic: inferior mesenteric plexus
- parasympathetic: via pelvic splanchnic nerves (from S2-S4)
Lymphatic drainage
Lymphatics travel with vessels to the inferior mesenteric group.
Related pathology
Siehe auch:
- Arteria iliaca interna
- Uterus
- Sigmavolvulus
- Ductus deferens
- Becken
- Mesenterium
- Arteria mesenterica inferior
- Rektum
- Dünndarm
- descending colon
- Harnblase
- Sigmakarzinom
- sigmoid arteries
- piriformis
- Ovar
- ocolon
- sigmoid mes
und weiter:
Assoziationen und Differentialdiagnosen zu Colon sigmoideum: