Abdominal Anatomy

Question 1

Caecum

Answer 1

Location - proximal to right colon below the ileocacal valve, intraperitoneal

Posterior relations

• psoas
• iliacus
• femoral nerve
• genitofemoral nerve
• gonadal vessels

Anterior relations - gretaer omentum

Arterial Supply - ileocolic artery

Lymphatic drainage - mesenteric nodes accompany the venous drainage

Note - most distensible part of the colon, so in LBO with a competent ileocaecal valve, this is the most likely site of perforation

Question 2

Spleen - relations, contents, size, weight, location, function

Answer 2

Superiorly - diaphragm
Anteriorly - gastric impression
Posteriorly - kidney
Inferiorly - colon
Hilim - tail of pancreas and splenic vessels (splenic artery divides here, branches pass to the white pulp transporting plasma)

Contents
White pulp - immune function, contains central trabecular artery, the germinal centres are supplied by arterioles called penicilliary radicles
Red pulp - filters abnormal red blood cells

Size - 12.5cm x 7.5cm
Weight - 150g

Location - lies obliquely with it long axis aligned to the 9th, 10th and 11th ribs

Function

• filtration of abnormal blood cells and foreign bodies such as bacteria
• immnity - IgM, production of properdin and tuftsin which help target fungi and bacteria for phagocytosis
• haematopoeisis - up to 5th month gestation or in haematological disorders
• pooling - storage of 40% platelets
• iron reutilisation
• storage of monocytes