Anatomy Tables - Kidneys & Retroperitoneum

Viscera

Organ/Part of Organ Location/Description Notes
kidney (N334, N342, TG5-30A, TG5-30B, TG5-30C, TG5-31B, TG5-31C, TG5-42) excretory organ of the urinary tract located on the posterior abdominal wall retroperitoneal; right kidney is lower than the left - its superior pole reaches the 12th rib; superior pole of the left kidney reaches as high as the 11th rib; kidneys develop from the intermediate mesoderm in the embryo
calyx, minor (TG5-32B) portion of the urinary collecting system within the kidney that drains one renal papilla one renal papilla projects into the lumen of one minor calyx; several minor calyces unite to form a major calyx (Greek, calyx = cup)
calyx, major (TG5-32B) portion of the urinary collecting system within the kidney that drains several minor calyces major calyx collects urine from several renal papillae; all major calyces unite to form the renal pelvis (Greek, calyx = cup)
pararenal fat (TG5-31B) extraperitoneal fat surrounding the kidney pararenal fat is located external to the renal fascia
perirenal fat (TG5-31B) extraperitoneal fat surrounding the kidney perirenal fat is located within the renal fascia; it is also located within the renal sinus surrounding the calyces and blood vessels
renal columns (TG5-32B) columns of tissue that are histologically identical to tissue found in the renal cortex, but which are located in the medulla between the renal pyramids interlobar arteries pass from the renal sinus to the renal cortex within the renal columns
renal cortex (TG5-32B) outer layer of kidney renal cortex contains the majority of the glomeruli
renal fascia (TG5-31B) a fascial pouch derived from extraperitoneal connective tissue that contains the kidneys, the suprarenal glands, the renal vessels and perirenal fat renal fascia of the right and left sides is joined across the midline in close relationship to the renal aa. and vv.; renal fascia encapsulates the inferior vena cava and aorta at the level of origin of the renal vessels; do not confuse renal fascia with the renal capsule - the renal capsule is histologically part of the kidney and there is no fat between it and the kidney
renal hilum (TG5-32B) opening on medial margin of the kidney leading into the renal sinus the renal vessels enter/leave the kidney at the hilum; the renal pelvis leaves the kidney at the hilum
renal medulla (TG5-32B) inner layer of the kidney renal medulla contains most of the tubules of the kidney organized as renal pyramids; renal columns consist of cortex-like tissue arranged between the pyramids in the renal medulla
renal papilla (TG5-32B) tip of renal pyramid projecting into a minor calyx several minor calyces combine to form a major calyx; all of the major calyces in the kidney unite to form the renal pelvis (Latin, papilla = a nipple)
renal pelvis (TG5-32B) large collecting duct for urine that is formed by the union of the major calyces renal pelvis is the dilated origin of the ureter; it is located at the renal hilum and is surrounded by the renal sinus
renal pyramid (TG5-32B) cone-shaped arrangement of tubules in the renal medulla tip of the renal pyramid (papilla) projects into a minor calyx
renal sinus (TG5-32B) hollowed out area on the medial margin of the kidney renal sinus opens at the renal hilum; it contains the renal aa. and vv., major calyces and renal pelvis, perirenal fat
ureter (TG5-32B, TG5-30B) muscular tube that serves as the duct of the kidney to carry urine to the bladder ureter is continuous proximally with the renal pelvis; it passes over the pelvic brim medial to the testicular/ovarian vessels; it passes obliquely through the posterior wall of the urinary bladder and drains at the posterolateral angle of the vesical trigone (Latin, ureter/oureter = urinary canal)
suprarenal gland (N347, TG5-31C) endocrine gland located superomedial to the kidney; right suprarenal gland is somewhat triangular in shape, left suprarenal gland is semilunar in shape suprarenal cortex manufactures corticosteroids; suprarenal medulla manufactures epinephrine and norepinephrine; suprarenal medulla receives preganglionic sympathetic innervation from the greater thoracic splanchnic n.; also known as: adrenal gland

Muscles

Muscle Origin Insertion Action Innervation Artery Notes Image
diaphragm (N185, N263, TG5-33) xiphoid process, costal margin, fascia over the quadratus lumborum and psoas major mm. (lateral & medial arcuate ligaments), vertebral bodies L1-L3 central tendon of the diaphragm pushes the abdominal viscera inferiorly, increasing the volume of the thoracic cavity (inspiration) phrenic nerve (C3-C5) musculophrenic a., superior phrenic a., inferior phrenic a. left crus attaches to the L1-L2 vertebral bodies, the right crus attaches to the L1-L3 vertebral bodies
iliacus (N263, TG5-33) iliac fossa and iliac crest; ala of sacrum lesser trochanter of the femur flexes the thigh; if the thigh is fixed it flexes the pelvis on the thigh femoral nerve iliolumbar a. inserts in company with the psoas major m. via the iliopsoas tendon
psoas major (N263, TG5-33) bodies and transverse processes of lumbar vertebrae lesser trochanter of femur (with iliacus) via iliopsoas tendon flexes the thigh; flexes & laterally bends the lumbar vertebral column branches of the ventral primary rami of spinal nerves L2-L4 subcostal a., lumbar aa. the genitofemoral nerve pierces the anterior surface of the psoas major m.
psoas minor (N263, TG5-33) bodies of the T12 & L1 vertebrae iliopubic eminence at the line of junction of the ilium and the superior pubic ramus flexes & laterally bends the lumbar vertebral column branches of the ventral primary rami of spinal nerves L1-L2 lumbar aa. absent in 40% of cases
quadratus lumborum (N263, TG5-33) posterior part of the iliac crest and the iliolumbar ligament transverse processes of lumbar vertebrae 1-4 and the 12th rib laterally bends the trunk, fixes the 12th rib subcostal nerve and ventral primary rami of spinal nerves L1-L4 subcostal a., lumbar aa. the lateral arcuate ligament of the diaphragm crosses the anterior surface of the quadratus lumborum m.

Arteries

Artery Source Branches Supply to Notes
aorta, abdominal (N264, TG5-34) the continuation of the descending thoracic aorta inferior phrenic aa. (2), celiac trunk, middle suprarenal aa. (2), lumbar aa. (4 pairs), superior mesenteric a., renal aa. (2), testicular/ovarian aa. (2), inferior mesenteric a., median sacral a., common iliac aa. (2) abdominal wall; gastrointestinal tract; body below the level of the respiratory diaphragm abdominal aorta passes posterior to the diaphragm (aortic hiatus) at the level of the T12 vertebral body
common iliac (TG3-62, TG5-29, TG5-30) abdominal aorta external iliac a., internal iliac a. pelvis, lower limb abdominal aorta bifurcates at the level of the L4 vertebral body to form the right and left common iliac aa.; the common iliac artery bifurcates anterior to the sacroiliac articulation into its terminal brs. (external iliac a. and internal iliac a.)
inferior phrenic (TG5-32) abdominal aorta superior suprarenal aa. diaphragm, suprarenal gland inferior phrenic a. is the first abdominal branch of the aorta; it may arise from the celiac trunk (Latin, phrenic = diaphragm)
lumbar (TG5-34) abdominal aorta anterior br., posterior br., spinal br. psoas major m., psoas minor m., quadratus lumborum m., spinal cord and vertebral column, deep back muscles the 4 lumbar arteries on each side arise from the posterior surface of the aorta at the level of vertebrae L1-L4; they course posterior to the psoas major m.
median sacral TG5-34) abdominal aorta 5th lumbar aa. sacrum median sacral a. appears to be the continuation of the abdominal aorta in the median plane, although it is much smaller in size
renal (NN 332 ,N335, TG5-34, TG5-32) abdominal aorta at the level of the upper border of the L2 vertebra inferior suprarenal a., apical segmental a., anterior br: superior anterior segmental a., middle anterior segmental a., inferior segmental a.; posterior br.: posterior segmental a. kidney, upper ureter, suprarenal gland the right renal a. is longer than the left renal artery; the right renal artery passes posterior to the inferior vena cava
suprarenal, inferior (N332, TG5-34, TG5-32) renal a. numerous unnamed branches inferior aspect of the suprarenal gland inferior suprarenal a. may anastomose with the superior suprarenal a.
suprarenal, middle (N332, TG5-34, TG5-32) abdominal aorta numerous unnamed branches medial side of the suprarenal gland middle suprarenal a. anastomoses with the superior suprarenal a. and the inferior suprarenal a.
suprarenal, superior (N332, TG5-34, TG5-32) inferior phrenic a. multiple small aa. superior aspect of the suprarenal gland superior suprarenal aa. are numerous small vessels that enter the suprarenal gland independently

Veins

Vein Tributaries Drains Into Regions Drained Notes
renal, left (N332, N341, TG5-34) left ovarian/testicular v., left suprarenal v., sometime the left inferior phrenic v. inferior vena cava left ovary/testis; left ureter; left kidney; left suprarenal gland; left part of the respiratory diaphragm left renal v. crosses the abdominal aorta under the origin of the superior mesenteric a., creating a site of potential compression of the left renal vein
renal, right (N332, N341, TG5-34) multiple tributaries exit the kidney inferior vena cava right kidney right renal v. is shorter than the left renal v.
suprarenal v. (N332, TG5-34) no named tributaries left: left renal v.; right: inferior vena cava suprarenal gland left suprarenal v. is usually joined by the left inferior phrenic v.
vena cava, inferior (N265, TG5-30, TG5-34) formed by the union of the paired common iliac vv; tributaries: lumbar vv. 1-4, right ovarian/testicular v., renal vv., right suprarenal v., right inferior phrenic v., hepatic vv. right atrium all of the body below the level of the respiratory diaphragm the inferior vena cava is longer than the abdominal aorta

Nerves

Nerve Source Branches Motor Sensory Notes
aorticorenal ganglion (N318, TG8-16, TG5-39) preganglionic sympathetic via the lesser thoracic splanchnic n. brs. to the renal plexus vascular smooth muscle of the brs. of the renal aa. pain from the kidney, suprarenal gland, upper ureter a sympathetic ganglion; located above or near the origin of the renal a. from the abdominal aorta (Greek, ganglion = a knot or swelling)
celiac ganglion (N318, N319, N320, TG8-16, TG5-39) preganglionic sympathetic axons arrive via the greater thoracic splanchnic n. postganglionic sympathetic axons distribute via the celiac plexus along brs. of the celiac trunk vascular smooth muscle of the brs. of the celiac trunk pain from the stomach, liver & biliary system, spleen, upper half of the duodenum & pancreas a sympathetic ganglion; usually 2 celiac ganglia are located on the abdominal aorta at the origin of the celiac trunk; brs. of the vagal trunks pass through the celiac ganglion without synapsing (Greek, celiac = belly + ganglion = a knot or swelling)
collateral ganglia splanchnic nn. (thoracic, lumbar) plexuses to abdominal & pelvic viscera smooth muscle in blood vessels supplying the abdominopelvic viscera pain from the abdominopelvic viscera sympathetic ganglia; also known as: preaortic ganglia which include: celiac, aorticorenal, superior & inferior mesenteric; brs. of the vagal trunks pass through but do not synapse in collateral ganglia
ganglia, myenteric preganglionic parasympathetic via anterior and posterior vagal trunks (gut proximal to the left colic flexure) and pelvic splanchnic nn. (gut distal to the left colic flexure) postganglionic parasympathetic via many short fibers smooth muscle of the gut wall none minute ganglia located within the myenteric plexus; parasympathetic terminal ganglia
ganglia, preaortic (TG8-03) splanchnic nn. plexuses to abdominal and pelvic viscera vascular smooth muscle of vessels that supply abdominopelvic viscera pain from abdominopelvic viscera also known as: collateral ganglia which include the celiac ganglion, aorticorenal ganglion, superior mesenteric ganglion and inferior mesenteric ganglion; preganglionic parasympathetic axons of vagal trunk origin pass through the preaortic ganglia but do not synapse there
ganglia, submucosal of the gut preganglionic parasympathetic arrive via branches of the anterior and posterior vagal trunks (gut proximal to the left colic flexure) and pelvic splanchnic nn. (gut distal to the left colic flexure) postganglionic parasympathetic via many short fibers secretomotor to glands in the mucosa of the gut none terminal parasympathetic ganglia; parasympathetic terminal ganglia; also known as: Meissner's plexus
ganglia, sympathetic chain preganglionic sympathetic fibers arrive via white rami communicantes of ventral primary rami of spinal nerves T1-L2 postganglionic sympathetic fibers depart via gray rami communicantes to all spinal nn.; internal & external carotid nn.; cervical cardiac brs.; thoracic direct visceral brs.; greater, lesser & least thoracic splanchnic nn.; lumbar splanchnic nn.; sacral splanchnic nn. dilator pupillae, vascular smooth muscle, arrector pili muscles, sweat glands, suprarenal medulla, heart, lungs and gut pain from viscera located lateral to the vertebral bodies in the neck, thorax & abdominopelvic cavity; the ganglia plus their interconnecting fibers are also known as the sympathetic trunk; preganglionic cell bodies are located in the intermediolateral gray matter of spinal cord levels T1-L2
ganglion, inferior mesenteric (TG5-39, TG5-40) preganglionic sympathetic axons from the intermesenteric plexus and the 2nd lumbar splanchnic n. contributes to the inferior mesenteric plexus; contributes to the superior hypogastric plexus vascular smooth muscle of brs. of the inferior mesenteric a. pain from descending colon and sigmoid colon; pain from upper rectum a sympathetic ganglion; located on the abdominal aorta at the origin of the inferior mesenteric a.; may be a series of small, indistinguishable ganglia rather than a single large one
ganglion, superior mesenteric (N318, N322, TG8-16, TG5-39) preganglionic sympathetic axons from the celiac plexus contributes to the superior mesenteric and intermesenteric plexuses vascular smooth muscle of brs. of the superior mesenteric a. pain from the lower half of the pancreas and duodenum, jejunum, ileum, cecum, appendix, ascending colon and transverse colon a sympathetic ganglion; located on the abdominal aorta at the origin of the superior mesenteric a.
greater thoracic splanchnic n. (N318, N320, N323, N344, TG8-16, TG5-39) neurons in the intermediolateral cell column of spinal cord levels T5-T9; the greater thoracic splanchnic nerve appears to arise by multiple contributions from the sympathetic trunk no named branches celiac ganglion; preganglionic fibers supply the adrenal medulla which releases epinephrine and norepinephrine into the blood pain from the abdominal viscera greater thoracic splanchnic n. passes through the crus of the respiratory diaphragm; postganglionic processes from the celiac ganglion spread down the aorta and distribute with its branches; they innervate the smooth muscle of these vessels and vascular smooth muscle in the organs supplied (Greek, splanchna = viscera)
hypogastric n. (TG6-19, TG6-19) superior hypogastric plexus inferior hypogastric plexus supplies vascular smooth muscle of the pelvic viscera pain from the pelvic viscera paired; hypogastric n. lies inferior to the common iliac vessels; it contains postganglionic sympathetic axons
hypogastric plexus, inferior (TG5-40, TG5-41) hypogastric nn. and sacral splanchnic nn. (postganglionic sympathetic axons); pelvic splanchnic nn. (preganglionic parasympathetic axons from the ventral primary rami of spinal nerves S2-S4) contributes branches to: uterine/vaginal plexus, vesical plexus, prostatic plexus sympathetic: supplies vascular smooth muscle of vessels supplying the pelvic viscera; parasympathetic: supplies smooth muscle of the pelvic viscera pain from the pelvic viscera; general visceral afferent from the pelvic viscera inferior hypogastric plexus lies between the pelvic viscera and the pelvic wall (Latin, plexus = a braid)
hypogastric plexus, superior (N318, TG5-40, TG5-41, TG5-39) intermesenteric plexus and lumbar splanchnic nn. (postganglionic sympathetic axons) hypogastric nn. (right and left) vascular smooth muscle of the pelvic viscera (sympathetic) pain from the pelvic viscera; general visceral afferent from the pelvic viscera superior hypogastric plexus is the continuation of the intermesenteric plexus; it crosses the pelvic brim (Latin, plexus = a braid)
intermesenteric plexus (N318, TG5-40, TG5-41, TG8-16, TG5-39) lumbar splanchnic nn. 1 and 2 renal, testicular (or ovarian) and ureteric brs. sympathetic: smooth muscle of vessels supplying the gut distal to the left colic flexure pain from the descending colon, sigmoid colon and rectum intermesenteric plexus is continuous with the superior mesenteric plexus; it continues inferiorly as the inferior mesenteric plexus and superior hypogastric plexus; intermesenteric plexus does not carry vagal parasympathetic fibers; located anterior to the abdominal aorta between the superior and inferior mesenteric aa. (Latin, plexus = a braid)
least thoracic splanchnic n. (N318, N320, N323, N344, TG8-16, TG5-39) neurons in the intermediolateral cell column of spinal cord level T12 no named branches renal plexus pain from the kidney and suprarenal gland least thoracic splanchnic n.pass through the crus of the diaphragm; it synapses in minute ganglia located in the renal plexus (Greek, splanchna = viscera)
lesser thoracic splanchnic n. (N318, N320, N323, N344, TG8-16, TG5-39) neurons in the intermediolateral cell column of spinal cord levels T10-T11; the lesser thoracic splanchnic nerve appears to arise by multiple contributions from the sympathetic trunk no named branches aorticorenal ganglion; pain from the kidney and suprarenal gland lesser thoracic splanchnic n. passes through the crus of the respiratory diaphragm; postganglionic processes from the ganglion supply vascular smooth muscle of branches of the renal a. and suprarenal aa.; kidney and suprarenal gland (Greek, splanchna = viscera)
lumbar splanchnic nn. (N318, TG5-40, TG5-41) lumbar sympathetic ganglia L1-L4 no named branches smooth muscle of vessels that supply the abdominal and pelvic viscera pain from abdominal and pelvic viscera sympathetic nerves; there are four of these on each side; lumbar splanchnic nn. contribute to preaortic abdominal plexuses (celiac, superior mesenteric, intermesenteric, superior hypogastric) (Greek, splanchna = viscera)
mesenteric plexus, inferior (N318, N322, TG8-16, TG5-39) intermesenteric plexus multiple unnamed nn. course along the branches of the inferior mesenteric a. sympathetic: smooth muscle of the vessels supplying the descending colon, sigmoid colon and rectum pain from the descending colon, sigmoid colon and rectum inferior mesenteric plexus contains no vagal parasympathetic fibers; pelvic splanchnic n. axons join the most distal nn. of the plexus near gut wall (Greek, mes = in the middle of + enteron = intestine; Latin, plexus = a braid)
mesenteric plexus, superior (N318, N322, TG8-16, TG5-39) celiac plexus, superior mesenteric ganglion multiple unnamed nn. course along the branches of the superior mesenteric a. sympathetic: smooth muscle of vessels supplying the lower pancreas, lower duodenum, jejunum, ileum, cecum, ascending colon and most of the transverse colon; parasympathetic (vagus): smooth muscle in the gut wall of same distribution area pain & GVA of the parts of the gut named at left superior mesenteric plexus contains a mixture of vagal (preganglionic parasympathetic) axons and postganglionic sympathetic axons (Greek, mes = in the middle of + enteron = intestine; Latin, plexus = a braid)
pelvic splanchnic n. (TG6-18A, TG6-18B, TG6-19A, TG6-19B) ventral primary rami of spinal nerves S2-S4 (cell bodies are located in the lateral horn gray of the sacral spinal cord) unnamed branches contribute to the pelvic plexus (inferior hypogastric) plexus smooth muscle and glands of the gut distal to the left colic flexure; smooth muscle and glands of all pelvic viscera none parasympathetic nerves; these contain preganglionic parasympathetic axons (Greek, splanchna = viscera)
vagus n. (TG5-40, TG5-41) medulla: dorsal motor nucleus (GVE preganglionic parasympathetic); inferior ganglion (GVA); nucleus ambiguus (SVE); superior ganglion (GSA); inferior ganglion(SVA) auricular br., pharyngeal br., superior laryngeal, superior and inferior cervical cardiac brs., recurrent laryngeal n., thoracic cardiac brs., brs. to the pulmonary plexus, brs. to the esophageal plexus, anterior and posterior vagal trunks SVE: intrinsic muscles of the larynx, pharynx (except stylopharyngeus), and palate (except tensor veli palatini); GVE: smooth muscle of the respiratory tree & gut (proximal to the left colic flexure), heart; secretomotor: mucous glands of the larynx, respiratory tree, pharynx and gut; secretomotor to digestive glands GSA: skin of the external auditory meatus; GVA: viscera of head, neck, thorax & abdomen proximal to the left colic flexure; SVA: taste from the epiglottis also known as: CN X, 10th cranial nerve; the vagus n. passes through the jugular foramen to exit the posterior cranial fossa; (Latin, vagus = wanderer due to its wide distribution to the body cavities)
esophageal plexus (TG5-40) right and left vagus (X) nn.; thoracic visceral brs. of the sympathetic trunk anterior and posterior vagal trunks preganglionic parasympathetic axons from the vagus n. supply smooth muscle and glands of the thoracic esophagus and abdominal gut and its derivatives proximal to the left colic flexure; postganglionic sympathetic axons from the thoracic visceral brs. supply vascular smooth muscle in the esophageal vessels vagus: GVA from the esophagus and abdominal gut proximal to the left colic flexure; thoracic visceral brs.carry pain from the esophagus during development of the gut, the stomach and esophagus rotate 90° to the right with the result that the left and right vagus nerves mix in the esophageal plexus and emerge as anterior and posterior vagal trunks (Latin, plexus = a braid)
phrenic n. (TG4-20, TG4-29) ventral primary rami of spinal nerves C3-C5 (cervical plexus) no named branches skeletal muscle of the respiratory diaphragm diaphragmatic pleura; some fibers contributed to the pericardium and to the adjacent mediastinal and costal pleurae phrenic n. crosses the anterior surface of the anterior scalene m. (Greek, phrenic = diaphragm)
femoral n. (TG3-19, TG3-20, TG3-21) lumbar plexus (ventral primary rami of spinal nerves L2-L4) anterior femoral cutaneous brs., nn. to: sartorius m., rectus femoris m., vastus lateralis m., vastus intermedius m., vastus medialis m., pectineus m. sartorius, rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, pectineus skin of anterior thigh passes under inguinal ligament lateral to femoral a.
femoral cutaneous, lateral (TG3-02, TG3-03, TG3-14) lumbar plexus (ventral primary rami of spinal nerves L2-L3) anterior & posterior brs. sympathetic motor innervation to skin skin of the lateral thigh cutaneous nn. carry postganglionic sympathetic axons to skin (Latin, cutis = skin)
genitofemoral n. (TG3-02, TG3-14, TG3-68) lumbar plexus (ventral primary rami of spinal nerves L1-L2) genital br., femoral br. cremaster m. skin of the anterior scrotum/labia majora & upper medial thigh genitofemoral n. lies on the anterior surface of the psoas major in the abdomen; the genital br. passes through the deep inguinal ring and inguinal canal; brushing the thigh elicits an elevation of the testis via the cremasteric reflex
gray ramus communicans (TG1-17B) cell bodies located in the sympathetic chain ganglia none carries postganglionic sympathetic axons to the spinal nerve; spinal nerve will carry those axons peripherally to the skin, blood vessels, etc. none gray rami communicantes connect the sympathetic chain to spinal nerves at all vertebral levels (Latin, ramus = a branch)
iliohypogastric n. (TG3-03, TG3-14) lumbar plexus (ventral primary ramus of spinal nerve L1) lateral and anterior cutaneous brs. muscles of the lower abdominal wall skin of the lower abdominal wall, upper hip and upper thigh iliohypogastric n. receives a contribution from T12 in approximately 50% of cases
ilioinguinal n. (TG3-03, TG3-19) lumbar plexus (ventral primary ramus of spinal nerve L1) anterior cutaneous br. (also known as: anterior labial/scrotal n.) muscles of the lower abdominal wall skin of the lower abdominal wall and anterior scrotum/labium majus ilioinguinal n. courses through the inguinal canal and superficial inguinal ring
lumbar n. ventral primary rami of spinal nerves L1-L5 contributes to the formation of the lumbar and sacral plexuses numerous: see lumbar and sacral plexuses numerous: see lumbar and sacral plexuses lumbar nn. enter into the formation of the lumbar and sacral plexuses and do not give branches directly to muscles or skin
lumbar plexus (TG8-13) ventral primary rami of spinal nerves L1-L4 branches of the lumbar plexus: iliohypogastric n., ilioinguinal n., genitofemoral n., lateral femoral cutaneous n., femoral n., obturator n., lumbosacral trunk (considered to be part of sacral plexus), brs. to the psoas major and minor mm., branches to the quadratus lumborum m. muscles of the lower abdominal wall; cremaster m., psoas major and minor mm., quadratus lumborum m., iliacus m.; muscles of the anterior and medial thigh and hip skin of the lower abdominal wall, skin of the anterior scrotum/labium majus, skin of the anterior and medial thigh and lateral hip lumbar plexus is noted for its variable branching pattern of nerves that supply the abdominal wall (Latin, plexus = to braid, a network of nerves, blood vessels, or lymphatic vessels)
lumbosacral trunk part of the ventral primary ramus of L4 united with the ventral primary ramus of L5 no named branches; it contributes to the formation of the sacral plexus muscles of the hip and posterior thigh see sacral plexus the lumbosacral trunk is not considered to be part of the lumbar plexus (Latin, plexus = a braid, a network of nerves, blood vessels, or lymphatic vessels)
obturator n. (TG5-08, TG5-09) lumbar plexus (ventral primary rami of spinal nerves L2-L4) anterior and posterior brs. muscles of the medial thigh: adductor longus m., adductor brevis m. and adductor magnus m., gracilis m., obturator externus m. skin of the lower medial thigh obturator n. passes through the obturator canal (Latin, obturare = close, obscure)
subcostal n. (TG5-02, TG5-38) ventral primary ramus of T12 lateral cutaneous br., anterior cutaneous br. muscles of the abdominal wall skin of the anterolateral abdominal wall the subcostal n. is equivalent to a posterior intercostal n. found at higher thoracic levels (Latin, costa = rib)
white ramus communicans (TG1-17B) cell bodies located in the lateral horn gray matter of spinal cord levels T1-L2; none axons contained within white rami communicantes will synapse on postganglionic cell bodies that will ultimately innervate the skin, viscera, glands, blood vessels, etc. pain from viscera is carried back to the spinal cord through the white ramus communicans white rami communicantes connect the sympathetic chain to spinal nerves at vertebral levels T1-L2; carries preganglionic sympathetic axons (Latin, ramus = a branch)


Lymphatics

Structure Location Afferents from Efferents to Regions drained Notes
cisterna chyli (N266, N546, TG5-37) between the abdominal aorta and the inferior vena cava anterior to the body of the L1 or L2 vertebra right and & left lumbar trunks; possibly the intestinal trunk thoracic duct all of the body below the respiratory diaphragm; all of the abdominal and pelvic viscera cisterna chyli is an enlargement of the lower end of the thoracic duct; it occurs in about 25% of individuals
common iliac nodes (N266, N546, TG5-37) along the common iliac vessels; over the sacral promontory external iliac nodes, internal iliac nodes lumbar (lateral aortic) chain of nodes lower limb; pelvic organs, perineum, lower part of the anterior abdominal wall common iliac nodes are approximately 6 in number
external iliac nodes (N266, N546, TG5-37) along the external iliac vessels superficial inguinal nodes; deep inguinal nodes; inferior epigastric nodes common iliac nodes lower limb; external genitalia; lower part of the anterior abdominal wall external iliac nodes are 8 to 10 in number
internal iliac nodes (N266, N546, TG5-37) along the internal iliac vessels lymphatic vessels from the pelvic viscera common iliac nodes, external iliac nodes pelvis, perineum and gluteal region internal iliac nodes are 4 to 8 in number
intestinal lymphatic trunk (N266, N546, TG5-37) left side of the abdominal aorta or between the abdominal aorta and the inferior vena cava near the level of the superior mesenteric artery union of efferent lymphatic vessels from the celiac nodes and superior mesenteric nodes left lumbar trunk or the cisterna chyli/thoracic duct large and small intestines intestinal lymph trunk carries lymph that is rich in fat; drains into the left lumbar trunk (70%), cisterna chyli (25%) or right lumbar trunk (5%)
lateral aortic nodes (N266, N546, TG5-37) along the inferior vena cava and abdominal aorta from the aortic bifurcation to the aortic hiatus of the diaphragm common iliac nodes; lymphatic vessels from the posterior abdominal wall and viscera efferents form one lumbar trunk on each side lower limb; pelvic organs; perineum; anterior and posterior abdominal wall; kidney; suprarenal gland; respiratory diaphragm also known as: lumbar nodes; the intestinal trunk drains into to the left lumbar trunk; the lumbar trunks unite to form the thoracic duct/cisterna chyli
lumbar nodes (N266, N546, TG5-37) also known as: lateral aortic nodes
lumbar trunk (N266, N546, TG5-37) between the lumbar vertebral bodies and inferior vena cava (right) or aorta (left) at the upper end of the lumbar chain of nodes lumbar (lateral aortic) nodes; the intestinal trunk joins the left lumbar trunk thoracic duct/cisterna chyli left lumbar trunk - left side of the body below the respiratory diaphragm, gut; right lumbar trunk - right side of body below the diaphragm lumbar trunks unite to form the lower end of the thoracic duct; an enlargement of the lower end of the thoracic duct (called the cisterna chyli) occurs in about 25% of individuals, and when it is present, the lumbar trunks drain into it
thoracic duct (TG4-10) between the esophagus anteriorly and the thoracic vertebral bodies posteriorly formed by the union of the lumbar lymph trunks, sometimes dilated to form a cisterna chyli junction of the left subclavian v. and the left internal jugular v. all of the body and limbs below the respiratory diaphragm; the left side of the chest, left upper limb and the left side of the head and neck above the diaphragm thoracic duct is the largest lymphatic vessel; it passes through the aortic hiatus on the right side of aorta; it swings to the left side of the esophagus at the T4-T5 intervertebral disc (at the level of the sternal angle)

Clinical Terms

Term Definition
femoral nerve iatrogenic injury During open abdominal surgeries (i.e., hysterectomy), rectractor blades are used to keep the cavity open. The blade may come to rest on the femoral nerve, crushing it as it lies in the groove between the iliacus and psoas major muscles.
renal calculus (kidney stone) The presence of calculi in the kidney or collecting system. The calculi are usually small (2-12mm) solid, crystalline, concretions that develop in the kidney and eventually pass through the genitourinary tract. Stones may be calcium (75-80% of all stones), uric acid, struvite, or cystine.
cystic kidney polycystic kidney disease (PKD) is a disorder that is characterized by the growth of numerous cysts in the kidneys. The cysts are filled with fluid. PKD cysts can replace much of the mass of the kidneys, thereby reducing kidney function and leading to kidney failure. When PKD causes kidneys to fail, which usually happens only after many years, the patient requires dialysis or kidney transplantation. About one-half of people with the primary form of PKD progress to kidney failure or end-stage renal disease (ESRD). PKD can cause cysts in the liver and problems in other organs, such as the heart and blood vessels in the brain. These complications help doctors distinguish PKD from the usually harmless "simple" cysts that often form in the kidneys in later years of life. (Greek, cystic/kystis = a bladder or pouch)
horseshoe/pelvic kidney A congenital abnormality in which the kidneys are united at the inferior poles (shaped like a horseshoe) and migrate up until stopped by the inferior mesenteric artery.
hiatal hernia A type of hernia that occurs when a portion of the stomach protrudes through the diaphragm (where the esophagus normally passes through). Obesity and smoking are considered risk factors. Hiatal hernia is often associated with reflux esophagitis. Symptoms include heartburn, difficulty swallowing, chest pain and belching. Treatment includes H2 antagonists, proton pump inhibitors, and antacids. (Latin, hernia = to rupture)
congenital diaphragmatic hernia A condition present at birth in which there is abnormal protrusion of abdominal contents upward through a defect in the diaphragm. This condition is treated as a surgical emergency due to interference with the infant's breathing. This compromises development of the lungs. It most commonly occurs on the left side (due to the liver's position on the right). Smaller, less serious diaphragmatic hernias may also be seen in adults. (Latin, hernia = to rupture)
abdominal aortic aneurysm (AAA) A distended and weakened area in the wall of the abdominal aorta, more common in those who suffer from atherosclerosis. The aneurysm is usually located below the renal arteries and above the aortic bifurcation. Symptoms include sudden, severe abdominal pain with radiation to the back. (Greek, aneurysm = a dilation)
IVP (intravenous pyelogram) a diagnostic test that follows the time course of excretion of a radiopaque contrast dye through the kidneys, ureters, and bladder after injection into a cutaneous vein.
ileus an obstruction of the intestines. (Greek, eileos = intestinal colic)

The material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest & Jaye Schlesinger
Published by ILOC, Inc., New York
Copyright © 1995, unauthorized use prohibited.
The excellent editorial assistance of
Dr. Pat Tank, UAMS
is gratefully acknowledged.