Spleen: Anatomy & Physiology

Anatomy

Structure

  • Borders:
    • Superior Border – May Be Notched
    • Anterior Border
    • Inferior Border
  • Surfaces:
    • Visceral – Concave & Irregular Surface
      • Several Imprints from Stomach, Kidney & Colon
    • Diaphragmatic – Convex & Smooth Surface

Spleen 1

Ligaments

  • Gastrosplenic Ligament
    • Hilum to Greater Curvature of Stomach
    • Contains Short Gastric Vessels & Left Gastroepiploic Artery
  • Splenorenal Ligament (Lienorenal Ligament)
    • Hilum to Left Kidney
    • Contains Splenic Artery/Vein & Tail of Pancreas
  • Splenophrenic Ligament
    • Superior Pole to Diaphragm
    • Avascular
  • Splenocolic Ligament
    • Inferior Pole to Colon
    • Avascular
  • Phrenicocolic Ligament (Hensing’s Ligament)
    • Diaphragm to Splenic Flexure of Colon
    • Supports Spleen but Not Directly Associated

Splenic Ligaments

Blood Supply

  • Splenic Artery
    • From Celiac Trunk
    • Runs Superior to Pancreas
    • Very Tortuous & Divides into 5-6 Branches
    • Most Common Variation: Short Splenic Trunk Divided into 6-12 Long Branches Entering the Spleen
  • Splenic Vein
    • To: Portal System
    • Posterior & Inferior to Artery (Posterior or Within Pancreas)

Splenic Artery (SA) & Vein (SV) 2

Physiology

Red Pulp (75-85%)

  • Function: Filters Damaged/Aged RBC & Debris
  • Structure:
    • Cords of Billroth – Connective Tissue with Large Population of Monocytes & Macrophages
    • Sinuses/Sinusoids – Drains into Venous System
    • Marginal Zone – Borders White Pulp
  • Action:
    • Blood Flows from Arteries into Cords
    • Cords Filter & Drain into Sinuses
    • Sinuses Drain into Venous System

White Pulp (15-25%)

  • Function: Immunologic
    • Most Common Ab: IgM
  • Structure: Malpighian Corpuscles
    • Lymphoid Follicles – B-Cells
    • Periarteriolar Lymphoid Sheaths (PALS) – T-Cells

Red Pulp (RP) & White Pulp (WP) 3

References

  1. Gray H. Anatomy of the Human Body (1918). Public Domain.
  2. Ham H, Kim SG, Kwon HJ, Ha H, Choi YY. Distal pancreatectomy with celiac axis resection for pancreatic body and tail cancer invading celiac axis. Ann Surg Treat Res. 2015 Oct;89(4):167-75. (License: CC BY-NC-4.0)
  3. Zhang Q, Waqas Y, Yang P, Sun X, Liu Y, Ahmed N, Chen B, Li Q, Hu L, Huang Y, Chen H, Hu B, Chen Q. Cytological study on the regulation of lymphocyte homing in the chicken spleen during LPS stimulation. Oncotarget. 2017 Jan 31;8(5):7405-7419. (License: CC BY-3.0)