Celiac plexus: topography and syntopy
The largest autonomic plexus of the retroperitoneal space, known in older literature as the solar plexus, is located on the anterior surface of the aorta, lateral to the celiac trunk. Skeletotopically, it is projected at the level of the XII thoracic vertebra. The lower boundary of this area is the site where the renal arteries branch off from the aorta. Anteriorly, the complex lies within the retroperitoneal adipose tissue of the posterior abdominal wall and is securely covered by the parietal peritoneum, which forms the posterior wall of the omental bursa.
Ganglion apparatus and innervation
The celiac plexus includes ganglia that receive the greater and lesser splanchnic nerves, which deliver preganglionic sympathetic fibers:
- Celiac ganglia (`ganglia celiaca`) — paired right and left elements.
- Aortorenal ganglia (`ganglia aortorenalia`) — two paired formations.
- Superior mesenteric ganglion (`ganglion mesentericum superius`) — an unpaired ganglion.
In these structures, signals are relayed to postganglionic fibers of the sympathetic system. From here, perivascular plexuses branch out to all abdominal organs.
Abdominal aortic plexuses below the celiac
Along the course of the abdominal aorta below the celiac plexus lies a chain of interconnected neural formations:
- Superior mesenteric plexus (`plexus mesentericus superior`).
- Intermesenteric plexus (`plexus intermesentericus`).
- Inferior mesenteric plexus (`plexus mesentericus inferior`), which is closely connected to the intermesenteric plexus and has its own ganglion of the same name.
Hypogastric plexuses and pelvic innervation
As the branches of the abdominal aortic plexus extend toward the sacral promontory, they form structures responsible for pelvic innervation:
- Superior hypogastric plexus (`plexus hypogastricus superior`), also known as the presacral nerve, divides and travels into the lesser pelvis cavity.
- Inferior hypogastric plexuses (`plexus hypogastrici inferiores dexter et sinister`) arise from the branches of the superior hypogastric plexus. They are joined by the parasympathetic component in the form of pelvic splanchnic nerves, which form networks within the pelvic organs.
Composition of nerve fibers
All the discussed autonomic plexuses of the abdominal cavity and pelvis contain a mixed composition of fibers. In addition to sympathetic and parasympathetic structures, afferent sensory viscerosensory fibers are present here, transmitting impulses from internal organs to the central nervous system.
Briefly: answers to topical questions
Which nerves provide parasympathetic innervation to the celiac plexus?
Parasympathetic fibers associated with the innervation of organs through the celiac plexus and its derivatives originate from the branches of the vagus nerve (n. vagus). Sources explicitly state that parasympathetic fibers to the organs of the upper floor of the abdominal cavity come from the n. vagus, while for the spleen they pass through the celiac plexus.
Which specific perivascular plexuses are formed from the celiac plexus to the abdominal organs?
From the celiac plexus and its branches to the abdominal organs, sources explicitly indicate the following related plexuses:
- Hepatic plexus — liver innervation is carried out by the hepatic plexus, which includes branches of the celiac plexus.
- Splenic plexus — formed by branches of the left half of the celiac plexus and located along the course of the a. lienalis.
- Suprarenal plexuses — formed with the participation of branches from the celiac, renal, phrenic, and abdominal aortic plexuses, as well as branches of the splanchnic and vagus nerves.
- Renal plexus (plexus renalis) — formed with the participation of branches of the celiac plexus; its branches penetrate the kidney perivascularly.
- Superior and inferior gastric plexuses, hepatic, splenic, and superior mesenteric plexuses are indicated as derivatives of the celiac plexus involved in stomach innervation.
- For the innervation of the duodenum, the celiac plexus, superior mesenteric plexus, hepatic, superior and inferior gastric, and gastroduodenal plexuses are specified.
Where is the superior hypogastric plexus topographically located relative to blood vessels and vertebrae?
Topographically, the superior hypogastric plexus (plexus hypogastricus superior) is located at the level of the V lumbar vertebra, descending toward the sacral promontory (promontorium). In relation to blood vessels, it is formed from descending branches of the abdominal aortic plexus, which accompanies the abdominal aorta. From its point of formation, the plexus diverges and descends into the lesser pelvis cavity.
Class and exam questions
Where is the celiac plexus skeletotopically located?
It is located at the level of the XII thoracic vertebra, on the anterior surface of the aorta lateral to the celiac trunk.
Which ganglia are part of the celiac plexus?
It includes two celiac ganglia, two aortorenal ganglia, and a single unpaired superior mesenteric ganglion.
What is the synonym for the superior hypogastric plexus?
The superior hypogastric plexus is also called the presacral nerve.
What fibers, besides sympathetic and parasympathetic, are present in the plexuses?
They invariably contain afferent sensory viscerosensory nerve fibers running from internal organs.
What else to study on this topic
- Anatomical features of the greater and lesser splanchnic nerves
- Topography of the intermesenteric and inferior mesenteric plexuses
- Pathways of perivascular plexus distribution to organs
- The role of pelvic splanchnic nerves in pelvic innervation
- Functional significance of afferent viscerosensory fibers
Master the complete topic in the "Topographic Anatomy" course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Celiac and Hypogastric Plexuses" and 2,777 more pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 91 video lessons on the subject
Other topics in the section "Topographic Anatomy of the Abdomen"
Free video lessons: topographic anatomyShort lessons with study notes — no registration required.
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.