Splenic artery

Where is it located and how does it run?

The splenic artery is a branch of the celiac trunk (truncus coeliacus), which arises from the anterior wall of the aorta at the level of TXII–LI.

Vessel topography:

• The artery courses tortuously along the superior border of the pancreas toward the splenic hilum.
• Initially, the artery lies posterior to the superior border of the pancreatic body, then runs superior to it.
• At the junction of the body and tail of the pancreas, it passes onto its anterior surface.
• The vessel then enters the lig. pancreaticolienale and reaches the splenic hilum.
• The artery is accompanied by the companion vein, the splenic vein (v. splenica / v. lienalis).
• The splenic plexus (plexus splenicus) runs along the course of the artery.

Age-related changes: In children and young adults, the artery is straight. After 30 years of age, tortuosity appears, and after 60 years, the shape becomes progressively tortuous, eventually becoming spiral. The length of the vessel in adults is 10–12 cm, but with age it can lengthen up to 26–32 cm.

What are the branches of the splenic artery?

Along its path to the spleen, the artery gives off several extra-organ branches to adjacent digestive organs:

• Pancreatic branches (rr. pancreatici) — supply the pancreatic parenchyma. These include the dorsal pancreatic artery (a. dorsalis pancreatis), the greater pancreatic artery (a. magna pancreatica) supplying the body and tail, the artery of the pancreatic tail (a. caudae pancreatis), and others.
• Short gastric arteries (aa. gastricae breves) — 3 to 7 small branches passing through the gastrosplenic ligament to the gastric fundus.
• Left gastroepiploic artery (a. gastroepiploica sinistra) — runs along the greater curvature of the stomach from left to right and anastomoses with the right gastroepiploic artery.

How do the vessels branch within the spleen?

At the splenic hilum, the main trunk divides into 2 branches (superior and inferior) in 80–90% of cases, and less frequently into 3–4 branches. Subsequent intra-organ branching is as follows:

1. Splenic branches (rr. splenici) branch off from the splenic artery.
2. Trabecular arteries (aa. trabeculares) — run within the trabeculae of the spleen.
3. Central arteries (aa. centrales) — enter the pulp and pass through the lymphoid follicles of the white pulp.
4. Penicillar arterioles / penicilli (penicilli) — small terminal branches.
5. Capillaries drain directly into the splenic venous sinuses (sinus splenicus) in a closed circulation, or blood is poured into the reticular tissue of the red pulp in an open vascular system.

Innervation

Innervation of the vessel is provided by the splenic plexus (plexus splenicus), located along the course of the artery. It is formed by branches of the left half of the celiac plexus with contributions from the left suprarenal and left phrenic plexuses. The plexus contains viscero-sensory, sympathetic, and parasympathetic fibers.

Clinical significance

• Splenic infarction: Anastomoses between intra-organ arteries are rare and of small diameter. Thrombosis or embolism of the branches of a. lienalis frequently leads to localized ischemic splenic infarctions.
• Surgery (splenectomy): During splenectomy, ligatures are applied not to the main trunk of a. lienalis, but to its branches as close as possible to the splenic hilum. This is necessary to avoid the risk of damaging the tail of the pancreas. The artery is ligated first to reduce the organ's blood volume while venous outflow remains intact, after which the v. lienalis is ligated with two ligatures.

Class and exam questions

What else to study on this topic

• Celiac trunk (truncus coeliacus)
• Spleen (splen)
• Pancreas
• Portal vein (v. portae)

Other topics in the "Anatomical Structures" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.