Major arteries, veins and nerves of the bodyWhen we say red, blue, yellow–you might associate it with the flag of the Republic of Armenia. But if you’re an experienced anatomy student, you’ll know that in anatomy atlases blue usually refers to veins, red to arteries and yellow to nerves. Together, veins, arteries and nerves define neurovasculature.
Since sometimes you can get lost in textbooks while studying the extensive networks of neurovasculature, this page will provide you with an exclusive introduction to the intricate network of vessels and nerves that conduct blood and nerve impulses throughout the body.
By definition, an artery is a vessel that conducts blood from the heart to the periphery. All arteries carry oxygenated blood–except for the pulmonary artery. The largest artery in the body is the aorta and it is divided into four parts: ascending aorta, aortic arch, thoracic aorta, and abdominal aorta.
After receiving blood directly from the left ventricle of the heart, the aorta descends through the thorax and abdomen–giving rise to many branches that supply all the body regions with nutrient rich, oxygenated blood.
Head and neck
- The brachiocephalic trunk gives rise to the right common carotid and right subclavian arteries.
- The common carotid arteries each branch into the internal and external carotid arteries. Internal carotid arteries together with vertebral arteries supply the brain, while external carotid arteries supply the face and neck.
- The subclavian arteries give rise to vertebral arteries, and then continue on to the axilla, where they become axillary arteries and supply the upper limb.
Learn everything about the head and neck arteries through our articles, quizzes and video tutorials.
Arteries of the trunk include the: thoracic aorta, celiac trunk, superior mesenteric artery, inferior mesenteric artery, and common iliac arteries (with its terminal branches internal iliac and external iliac arteries).
The thoracic aorta is the part of descending aorta that passes through the thorax. It supplies the mediastinum, bronchi, esophagus, pericardium, and thoracic surface of the diaphragm with its arterial branches. The abdomen is supplied by the branches of the abdominal aorta: celiac trunk, renal artery, gonadal artery, mesenteric arteries, and common iliac arteries. They supply the stomach, liver, spleen, gastrointestinal tract, kidneys, as well as the testes in males, and ovaries and uterus in females.
The terminal branches of abdominal aorta are the common iliac arteries. They bifurcate into their own two terminal branches (internal and external) with the internal iliac supplying the pelvis and the external iliac continuing down the lower limb as the femoral artery.
The main artery of the upper limb is the axillary artery–it is a continuation of the subclavian artery. The axillary artery continues down the upper arm as the brachial artery, then splits into the ulnar and radial arteries in the forearm. The hand is supplied by the terminal branches of the ulnar and radial arteries, which anastomose and form two arterial arches: superficial and deep palmar arches.
The main artery of the lower limb is the femoral artery and its continuation–the popliteal artery. The femoral artery supplies the gluteal region and the thigh before it continues as the popliteal artery in the posterior knee.
The popliteal artery then supplies the knee region, before splitting into two branches which supply the leg: anterior tibial and posterior tibial (gives off the fibular artery as a branch). These three arteries supply the the leg. The foot is supplied by the dorsalis pedis artery (a continuation of the anterior tibial artery) and the posterior tibial artery.
A vein is defined as a vessel that conducts blood from the periphery to the heart. All veins carry deoxygenated blood–except for the pulmonary vein. The largest veins are the superior and inferior vena cava, and both drain directly into the right atrium of the heart. All veins of the systemic circulation eventually drain back into one of these.
Head and neck
Deoxygenated blood from the brain, head, and neck ultimately drain into one of the three jugular veins: external, internal, or anterior.
- Venous blood of the brain and meninges drains into the dural venous sinuses, which drain into the internal jugular vein.
- Blood from the scalp and face drain into the veins that accompany the arteries of the scalp and face, which ultimately drain into the external jugular vein.
- Venous blood of the neck drains into the anterior jugular vein.
From here: both the external jugular and anterior jugular veins drain into the subclavian vein; the internal jugular vein merges with the subclavian vein to form the brachiocephalic vein; and the left and right brachiocephalic veins combine, creating the superior vena cava.
Veins of the trunk converge from the thorax, abdomen, and pelvis towards the heart. Deoxygenated blood from the thorax ultimately drains into the superior vena cava (SVC). The major thoracic tributaries of the SVC include the: azygos venous system, pulmonary veins, internal thoracic vein and cardiac veins. Venous blood from the abdomen and pelvis is drained by the inferior vena cava. Its main tributaries are the:
- Common iliac and internal iliac veins which drain the pelvis
- Lumbar, renal, gonadal, suprarenal, phrenic, portal, and hepatic veins which drain the abdomen
The hand is drained by the dorsal venous network which gives rise to the basilic and cephalic veins. These two veins drain the superficial structures of the forearm, while the deep structures are drained by the radial and ulnar veins. These two veins then merge join to form the brachial vein. Further up the arm, the basilic and brachial veins unite into the axillary vein, into which the cephalic vein drains too.
All upper extremity veins eventually drain into the axillary vein. It drains the upper arm and shoulder. The axillary vein ultimately empties into the subclavian vein, which belongs to the venous system of the superior vena cava.
The lower limb veins are the dorsal venous arch, anterior tibial, posterior tibial, fibular/peroneal, popliteal, femoral, great saphenous, small saphenous, external iliac, and common iliac veins. These are separated into deep and superficial venous systems.
From the periphery, deep structures of the leg are first drained by the dorsal venous arch of the foot. This arch drains the foot then gives rise to the anterior tibial, posterior tibial, and fibular/peroneal veins. These three drain the leg and unite into the popliteal vein at the posterior knee. The popliteal vein continues as the femoral vein, which drains the thigh. Once the femoral vein passes under the inguinal ligament, it continues as the external iliac vein, which drains into the common iliac vein.
Superficial structures of the leg are drained by the great saphenous and the small saphenous veins. They are formed by dorsal venous arches of the foot, and they drain into the femoral vein and popliteal vein respectively. The right and left common iliac veins unite and form the inferior vena cava. The gluteal (hip) region is drained directly into the internal iliac vein by superior and inferior gluteal veins.
The nervous system is a complex network of nerves and neural tissues which generate and transmit commands from the brain and spinal cord to tissues and organs. It has two anatomical divisions–the brain and spinal cord make the central nervous system, while the nerves that emerge from them and reach target tissues make up the peripheral nervous system. Peripheral nerves emerge from the central nervous system. There are 12 pairs of cranial nerves which arise from the brain, and 31 pairs of spinal nerves which extend from the spinal cord. In certain areas of the body peripheral nerves interconnect, creating neural networks called plexuses.
The nervous system can also be divided by function. The somatic nervous system is the part under voluntary control–for example contraction of skeletal muscle. Some other parts of the nervous system are under involuntary control, such as heart rate and breathing. This involuntary part of the nervous system is called the autonomic nervous system. It has two subdivisions:
- Sympathetic nervous system produces the “fight or flight” state as it is the part of the autonomic nervous system which is mostly active during stress.
- Parasympathetic nervous system dominates during rest, and is more active in “rest and digest” or “feed and breed” activities.
Check out this Kenhub content to learn more about the autonomic nervous system.
Head and neck
The major nerves of the head and neck come from the 12 pairs of the cranial nerves and the cervical plexus. The 12 pairs of the cranial nerves originate from the brain. They are the: olfactory (CN I), optic (CN II), oculomotor (CN III), trochlear (CN IV), trigeminal (CN V), abducens (CN VI), facial (CN VII), vestibulocochlear (CN VIII), glossopharyngeal (CN IX), vagus (CN X), accessory (CN XI), and hypoglossal nerves (CN XII). They provide sensory, motor, and autonomic innervation to almost all the structures of the head.
The cervical plexus supplies the skin and muscles of the anterolateral neck, the superior thorax, and an area of the scalp between the auricle and the external occipital protuberance. It is a network of nerves formed by the ventral rami of cervical spinal nerves C1-C5.
The trunk has a rich somatic and autonomic neural supply. You may wonder why, but there’s more than 30 of our organs packed in there, and they all need innervation. So let’s take a look at the trunk nerves and clarify them once and for all.
The thoracic wall is supplied by the lateral and medial pectoral nerves, 11 intercostal nerves (T1-T11) and the subcostal nerves (T12). The diaphragm is supplied by the left and right phrenic nerves (C4). Autonomic innervation for thoracic viscera comes from pulmonary and cardiac plexuses (C1-T1). The vagus nerve provides parasympathetic fibers and the sympathetic trunk provides the sympathetic input for those plexuses.
The abdominal walls are supplied by the thoraco-abdominal nerves (T7-T11), subcostal nerve (T12) and the upper three branches of the lumbar plexus (L1-L4), which we have covered in the lower limb section. Autonomic innervation for the abdominal viscera comes from spinal levels T5 to L2.
The lower thoracic and lumbar splanchnic nerves provide sympathetic innervation, while the vagus and pelvic splanchnic nerves carry parasympathetic fibers. The sympathetic fibers end within prevertebral sympathetic ganglia around the roots of the major branches of the abdominal aorta. The parasympathetic fibers end within ganglia scattered over the abdomen, close to the abdominal organs.
The pelvic walls are mainly innervated by the sacral and coccygeal spinal nerves. Autonomic innervation for the pelvic viscera comes from inferior hypogastric and pelvic plexuses. Sympathetic sources for them are the superior hypogastric plexus, while the parasympathetic are the pelvic splanchnic nerves. Sexual arousal is mediated by parasympathetic fibers, while sympathetic portion provides sensation of pleasure during orgasm.
The major nerves of the upper limb come from the brachial plexus–formed by the ventral rami of spinal nerves C5-T1.
Main branches of the brachial plexus are the musculocutaneous, axillary, radial, median, and ulnar nerves. The first two predominantly supply the shoulder and the arm, while the radial, median, and ulnar nerves mainly supply the forearm and the hand. Lateral and medial pectoral nerves also originate from brachial plexus, but innervate the pectoralis major muscle in the trunk.
The lower limb is supplied by branches of the lumbar plexus and sacral plexus, together forming the lumbosacral plexus. The lumbar plexus is formed by the ventral rami of L1-L4, giving rise to six nerves that innervate parts of the abdominopelvic region and the lower limb: the iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, obturator and femoral nerves.
It is the latter three nerves which supply the lower extremity. The sacral plexus is formed by the ventral rami of L5-S2, which gives rise to five sacral nerves: the superior gluteal, inferior gluteal, sciatic, posterior femoral cutaneous, and pudendal nerves, nerve to piriformis, nerve to obturator internus, and nerve to quadratus femoris.
The region of the hip is supplied the femoral, obturator and superior gluteal nerves. The anterior thigh is supplied by the femoral nerve and its cutaneous branch, the saphenous nerve. The posterior thigh is supplied by the sciatic nerve, while the medial thigh is predominantly supplied by the obturator nerve.
The leg is supplied by the tibial nerve and the common fibular (peroneal) nerve and its branches (superficial and deep). All of these are branches of the sciatic nerve. The foot is supplied by branches of the medial and lateral plantar nerves, both of which originate from the tibial nerve.